# ea: easter location: 3-57 (between jvl and sbd). references: Anderson and Nusslein-Volhard, 1984, Nature 311: 223-27 (fig.). 1986, Symp. Soc. Dev. Biol. 44: 177-94. Gametogenesis and the Early Embryo (J. Gall, ed.). Alan R. Liss, New York, pp. 177-94. Chasan and Anderson, 1989, Cell 56: 391-400. phenotype: Maternal effect lethal; both recessive loss-of- function and dominant gain-of-function alleles female sterile. Embryos produced by females homozygous for recessive alleles are dorsalized; lack ventral and lateral elements similar to embryos produced by dl/dl females; dorsal folds extend around circumference of embryo; lateral head fold and ventral furrow fail to form; germ band does not extend, and cuticle forms a tube with dorsal characteristics throughout. Degree of dor- salization proportional to level of ea expression as demon- strated by hypomorphic and temperature-sensitive alleles. Temperature sensitive period as demonstrated by ea14 from the time of pole-cell formation to gastrulation; developmental Northern blots demonstrate the presence of transcript in the ovaries and increased levels during the first four hours of embryonic development followed by a marked decline between hours four and six. Partial rescue of mutant phenotype achieved by injection of cytoplasm or poly-A+ RNA from wild- type embryos or embryos from females homozygous for other dorsal-group mutants; spatial source of donor cytoplasm unim- portant; degree of rescue reduced with distance from site of injection; complete rescue producing viable and fertile adults achievable with injection of purified ea+ mRNA. tw, a zygoti- cally active member of the dorsal group of genes, is not expressed in such embryos (Thisse, Stoetzel, El Messal, and Perrin-Schmidt, 1987, Genes Dev. 1: 709-15); furthermore strong alleles allow zen expression ventrally where it is not normally observed (Rushlow, Frasch, Doyle, and Levine, 1987, Nature 330: 583-86); periodicity of ftz stripes slightly dis- rupted in embryos from ea mothers (Carroll, Winslow, Twombly, and Scott, 1987, Development 99: 327-32). Females heterozy- gous for fully penetrant dominant alleles are sterile; the offspring of eaD3/+ females display ventralization or lateral- ization as indicated by lateral extension of the denticle bands; patches or rings of denticles may encircle the embryo; however, the mesoderm, the most ventral pattern element, is not increased; dorsal structures such as filzkorper, antennal and maxillary sense organs are absent; field of dorsal hairs greatly reduced. eaD2/+ females are lateralized, producing embryos that lack presumptive mesoderm and have no ventral furrow, show dorsoventrally symmetrical folding at gastrula- tion with the lateral head fold encircling the embryo, and do not undergo germ band extension. Injection of ea-deficient embryos with 200 times the quantity of mRNA required for com- plete rescue does not cause ventralization, indicating that gain of function alleles are not merely hypomorphic in nature. alleles: The only dorsal-group gene, other than Tl, that mutates at substantial frequency to dominant alleles; dominant alleles designated eaD. allele origin synonym ref ( comments __________________________________________________________ ea1 EMS 3 strong allele ea2 EMS 3 ea3 EMS 3 ea4 EMS 3 ea5 EMS 3 ea6 EMS 3 ea7 EMS 3 ea8 EMS 3 ea9 EMS 3 ea10 EMS 3 ea11 EMS 3 ea12 EMS ea111 3 weak allele ea13 EMS ea125 3 ea14 EMS ea818 3 temperature sensitive allele ea15 X ray eaD288RX1 3 eaD2 revertant ea16 P ea83lRPA 1 eaD3 revertant ea17 P ea83lRPI 1 eaD3 revertant ea18 P ea83lRPN 1 eaD3 revertant ea19 P ea83lRPX 1 eaD3 revertant eaD1 EMS ea5.13 1, 3 -> 9 EMS revertants -> 2 X ray revertants eaD2 EMS eaD288 3 eaD3 EMS ea83l 1, 3 -> 1 X ray revertant -> 4 P revertants eaD4 EMS ea84b 1, 3 incomplete penetrance eaD5 EMS ea84e 1 incomplete penetrance eaD6 EMS ea125.3 1 -> 11 EMS revertants eaD7 EMS eaD12a 2 eaD8 EMS eaD20n 2 eaD9 EMS eaD4102 2 eaD10 EMS eaD5022 2 ( 1 = Chasan and Anderson, 1989, Cell 56: 391-400; 2 = Erde- lyi and Szabad, 1989, Genetics 122: 111-27; 3 = Tearle and Nusslein-Volhard, 1987, DIS 66: 209-26. cytology: Placed in 88F2 by in situ hybridization (Chasan and Anderson). molecular biology: Locus identified in a chromosome walk by transposon tagging; restriction fragment harboring sites of P insertion recognizes mRNA of 1.5 kb. Shown to be the ea mes- sage by rescuing embryos of ea mothers by injection of hybrid selected message. cDNA selected from 0-3 hr embryo library by above restriction fragment shown to be full length by rescue of embryos with in vitro transcription product. Sequence of cDNA indicates a polypeptide of 392 amino-acids, 43,070 dal- tons, and containing a putative signal sequence. The N- terminal 127 residues show no homology with any known protein; the remaining residues, however, share homology with many extracellular serine proteases of the trypsin superfamily; in conserved segments of the catalytic domain there is 50% amino-acid identity, and over the entire catalytic domain, 30% identity. # eag: ether-a-go-go (J.C. Hall) location: 1-50.0 (1-45.3 according to Homyk and Grigliatti, 1983, Dev. Genet. 4: 77-97). origin: All alleles induced by ethyl methanesulfonate. references: Kaplan, 1969, DIS 44: 45. Kaplan and Trout, 1969, Genetics 61: 399-409. Ganetzky and Wu, 1983, J. Neurogenet. 1: 17-28. phenotype: Abnormal leg shaking under ether anaesthesia; aber- rant, repetitive firing of action potentials in larval nerves; potassium currents abnormal in larval muscles (Wu, Ganetzky, Haugland and Lin, 1983, Science 220: 1076-1078). eag Sh dou- ble mutants display greatly increased level of spontaneous neuronal activity and extreme behavioral phenotypes (Burg and Wu, 1989, Dev. Biol. 131: 505-14). alleles: eag1; eag4PM, weak behavioral abnormalities but is abnormal physiologically; eag101, hyperactive, flies and jumps well when raised at 22, flies poorly or not at all when raised at 29. (Homyk, Szidonya, and Suzuki, 1980, Mol. Gen. Genet. 177: 553-65); TSP during pupal stage (Homyk and Grigliatti, 1983, Dev. Genet. 4: 77-97). eag102, also causes accentuated jumping ability (Homyk et al.). cytology: Located in 12F6-13A4 based on uncovering by Df(1)RK2 = Df(1)12D2-E1;13A2-5, by Df(1)RK3 = Df(1)12E2-6;13A6-11, by Df(1)RK4 = Df(1)12F5-6;13A9-B1; and by Df(1)RK5 = Df(1)12E10- 11;13A8-B1; not uncovered by Df(1)KA9 = Df(1)12E2-3;12F5-13A1 (Kreber and Ganetzky). molecular biology: Region very close to, and likely to include, the locus cloned by Drysdale and Ganetzky (1985, Neurosci. Abstr. 11: 788). other information: eag mutations interact synergistically with Shaker mutations, i.e., double mutants are severely abnormal both behaviorally and physiologically (Ganetzky and Wu, 1983). # eagle: see eg # early: see eay # early: see lds # early C: see elyC # early-A: see aur # eas: easily shocked (J.C. Hall) location: 1-53.5. origin: Induced by ethyl methanesulfonate. synonym: PC80, RH11. references: Benzer, 1971, J. Amer. Med. Assoc. 218: 1015-22. Ganetzky and Wu, 1982, Genetics 100: 597-614. phenotype: Brief paralysis following exposure to mechanical shock; this phenotype suppressed by napts mutation at its per- missive temperature; release of neurotransmitter at larval neuromuscular junction is apparently normal. alleles: Two mutant alleles: eas1 and eas2. cytology: Placed in 14B5-18 based on its inclusion in Df(1)81h246 = Df(1)14B15-18;14E but not in Df(1)82a2y = Df(1)14B5-18;15A3-4 (Steller). other information: Separable by recombination from bss (which causes similar phenotype), to which eas is closely linked. # easter: see ea # eay: early (T. Schupbach) location: 2- {86}. origin: Induced by ethyl methanesulfonate. references: Schupbach and Wieschaus, 1989, Genetics 121: 101- 17. phenotype: Maternal-effect lethal or female-sterile mutant; homozygous females lay eggs which show no visible signs of development when observed under transmitted light in a stereo microscope; defective in fertilization or very early embryonic development. alleles: Seven alleles eay1 through eay7, originally designated OP, AWG, AWH, HL, PI, PQ, and SJ respectively. cytology: Placed in 55A-F since uncovered by Df(2R)PC4 = Df(2R)55A;55F. # eb: see seb # eb: extra bristles location: 2-32. origin: Spontaneous. references: Mostashfi and Koliantz, 1969, DIS 44: 51. phenotype: Increased bristle number on mesonotum and scutellum; average of two extra scutellar and two extra mesonotal bris- tles. # Eb: see E(B) # ebonized: see seb # ebo: ellipsoid body open (J.C. Hall) location: 1-0.6. origin: Induced by ethyl methanesulfonate. references: Heisenberg, Borst, Wagner, and Byers, 1984, J. Neu- rogenet. 2: 1-30. phenotype: Ellipsoid body of central brain abnormally flat and broad; learning normal in tests using olfactory stimuli. # ebony: see e # ec: echinus location: 1-5.5. origin: Spontaneous. discoverer: Bridges, 15l6. phenotype: Eyes large and bulging. Eye surface rough; facets large. Wings rather short and broad. Body thickset. Tends to remove dorsocentrals (posterior more than anterior) and posterior notopleurals; may also add dorsocentrals anterior to anterior dorsocentrals whether or not posterior bristles removed (Sturtevant). Reduces number of mesopleural hairs in h homozygotes (Sturtevant, 1969, Dev. Biol. 21: 48-61). ec is visible in +/ec/ec triploids (Gersh). RK1. cytology: 3E8 or F1 [Lefevre, 1976, The Genetics and Biology of Drosophila (Ashburner and Novitski, eds.). Academic Press, London, New York, San Francisco, Vol. 1a, p. 59]. # ecd: ecdysone location: 3-1.5. references: Garen, Kauvar, and Lepesant, 1977, Proc. Nat. Acad. Sci. USA 74: 5099-103. Redfern and Bownes, 1983, Mol. Gen. Genet. 189: 432-40. phenotype: Temperature-sensitive recessive lethal. At 29, the nine-fold increase in |-ecdysone content during embryogenesis occurs normally in ecd homozygotes. Accompanied by normal increases in dopa-decarboxylase and dopamine acetyltransferase activity (Marsh and Wright, 1980, Dev. Biol. 80: 379-87). The four-fold increase during the first larval instar is reduced to 40% of normal; the additional twelve-fold increase normally occurring at pupariation eliminated. Embryonic development of ecd at 29 normal, but first larval molt delayed and death usually occurs by end of second instar; shift down to 20 at mid second instar produces full yield of adult pro- geny. Larvae shifted from 20 to 29 midway through third instar fail to pupate and survive as larvae for up to 3 weeks; ring gland, salivary glands, and brain of nonpupariating lar- vae are smaller than wild type; such ring glands cultured in vitro secrete ecdysone at lower than normal levels. Effects of 29 on third instar reversible by ecdysone feeding or by shift down to 20 within 3-5 days of shift up; after that imaginal disks cannot differentiate; ecd imaginal disks develop nor- mally at 29 when implanted in a wild-type host. A heat pulse during larval development results in cell death with conse- quent abnormalities in emerging adults. At 29, third instar larvae exhibit abnormally low dopadecarboxylase activity (Kra- minsky, Clark, Estelle, Gietz, Sage, O'Connor, and Hodgetts, 1980, Proc. Nat. Acad. Sci. USA 77: 4175-79); Marsh and Wright) and high urate oxidase activity (Krase and Friedman, 1979, Genetics 91: s62-63); ecdysone feeding effects normal levels. Transfer to restrictive conditions at the beginning of the pupal stage leads to death as pharate adults and to the elimination of mechanosensory chaetae; Non-sensory chaetae and other sensilla not affected. Chaetae loss is autonomous as seen in homozygous clones produced by somatic exchange and in ecd discs passed through metamorphosis in wild type hosts under restrictive conditions (Sliter, 1989, Development, 106: 347-54). Sensitivity to restrictive temperature disap- pears in 24 hour pupae. ecd fails to block midpupal increase in ecdysone titer (Marsh and Wright). Shifting newly emerged ecd adults to 29 results in drastically reduced ecdysone titers and sterilizes both males and females; reversible by shift back to 20; temperature-sensitive periods and therefore the times that ecdysone is required for embryonic development, chorion formation, and vitellogenesis are 1-2 days before ovi- position, 24 hr prior to oviposition, and prior to stage 7, respectively (Audit-Lamour and Bussin, 1981, J. Insect Phy- siol. 27: 829-37). alleles: In addition to ecd1 described above, ecd2, a noncondi- tional, ethyl-methanesulfonate-induced allele recovered by Sliter, Henrich, Tucker, and Gilbert (1989, Genetics 123: 327-36). cytology: Placed in 62C4-D5 based on its inclusion in Df(3L)R- R2 = Df(3L)62B2-4;62D3-5 but not Df(3L)R-G5 = Df(3L)62A10- B1;62C4-D1 (Sliter et al.). # Ecdysone-dependent gene: see Edg # Ecdysone-inducible: see E74 # Ecdysteroid-inducible polypeptide encoded in 55BD: see Eip55BD # echinoid: see ed # echinus: see ec # ecl: echinus like location: 1- {8} [to the left of fl(1)302]. origin: Induced by ethyl methanesulfonate. references: Steinmann-Zwicky, 1988, EMBO J. 7: 3889-98. phenotype: Like ec. cytology: Placed in 4C5-E1 based on its inclusion in Df(1)rb13 = Df(1)4C5-6;4D3-E1. Not included in Df(1)rb23 or Df(1)rb34 both of which overlap the left end of of Df(1)rb13 and include rb and peb as does Df(1)rb13. # Eco: Extra combs location: 2-84. discoverer: Duncan. phenotype: Sex combs formed on second and third pairs of legs; middle leg transformed to first leg; fifth and sixth tergites transformed to sixth and seventh, respectively. Clonal analysis indicates late activity. alleles: Hypomorphic and amorphic alleles and deletions have been identified. # ecs: see BRC # ed: echinoid location: 2-11.0. origin: Spontaneous. discoverer: Bridges, 31a16. phenotype: Eyes large and rough. Easily classified, although not as extreme as ec. Su(S)/ed is echinoid in phenotype (Gel- bart). RK1. cytology: Placed in 24D3-4 on the basis of its inclusion in the region of overlap of Df(2L)ed-Szl = Df(2L)24A3-4;24D3-4 and Df(2L)M24F-11 = Df(2L)24D3-4;25A2-3 (Szidonya and Reuter, 1988, DIS 67: 77-79; 1987, Genet. Res. 210: 429-36). # Edg: Ecdysone-dependent gene Four genes identified in a differential screen of a genomic library with cDNA isolated from imaginal discs pulsed with 20-hydroxyecdysone, 20-HE (Fechtel, Natzle, Brown, and Fris- trom, 1988, Genetics 120: 465-74). All of these genes accu- mulate transcripts in imaginal disc tissue, beginning at six to nine hours, following a six-hour 20-HE pulse, but not in the absence or continual presence (except Edg64CD) of 20-HE; mRNA's of all four enriched in membrane-bound polysome frac- tions of imaginal discs. Translation product from hybrid selected mRNA of Edg78E, but not the other three, reacts with polyclonal antibodies prepared against purified pupal cuticle proteins. genetic cytological locus location location mRNA on Northerns _________________________________________________________ Edg42A 2-{55} 42A 3.0 kb Edg64CD 3-{19} 64C-D 5.4, 5.0, 3.9, 3.9 kb Edg78E 3-{47} 78E 0.6 kb Edg84A 3-{47} 84A1 0.9 kb # ee: extra eye (W.K. Baker and J.C. Hall) location: 2-18.0 (between dp and spd). origin: Spontaneous. discoverer: Averhoff. references: Marcey and Stark, 1985, Dev. Biol. 107: 180-97. Baker, Marcey and McElwain, 1985, Genetics 111: 67-88. phenotype: Flies from extra eye stocks show pattern duplica- tions of head morphology in varying degrees; small duplica- tions may appear as a few extra orbital bristles, whereas extreme expression involves well-formed, supernumerary, com- pound eyes on the vertex with associated orbital structures; ectopic eye is a mirror-image partial duplication of the ipsi- lateral eye. Occasionally, ocelli may be duplicated and rarely the antennae; a line of mirror-image symmetry often can be recognized between normal structures and their duplicated counterparts; structural deficiencies, particularly in the occipital region, are common. Penetrance is temperature sen- sitive (72% at 29 and 25, 43% at 19); temperature-sensitive periods in mid-embryogenesis and mid-first instar. There is no evidence of cell death in eye-antenna imaginal disc; first evidence of disc hyperplasia in late third instar. Fine- structure anatomy and physiology of photoreceptors in extra eyes appear normal; electroretinograms suggest that photore- ceptors in extra eyes can make functional synaptic connec- tions, although neuroanatomical studies show receptor- central-nervous-system innervations only rarely; the rare supernumerary antennae, however, have receptor cells whose axons innervate the ventral brain. cytology: No recombination has been observed between ee and a P-element insertion at 26D1-2. other information: ee is incompletely penetrant, being influ- enced profoundly by apparent enhancer mutations on 1, 2, and 3; it behaves as a partial dominant when appropriate enhancers are made homozygous; P elements also serve as enhancers (Mar- cey). Penetrance is temperature-sensitive, being higher at 25 than at 19; temperature-sensitive periods occur at mid-late embryogenesis and at early first instar. #*ef: elfin location: 1- (rearrangement). origin: Induced by triethylenemelamine (CB. 1246). discoverer: Fahmy, 1952. references: 1959, DIS 33: 86. phenotype: Small fly with slightly excess melanization. Wings proportionally smaller, slightly altered in shape, and warped. Abdominal tergites often broken and abnormally pigmented. Males viable but sterile. RK3A. cytology: Associated with T(1;2)ef = T(1;2)14C8-D1;2R. # Ef1(1: Elongation factor 1( #1 location: 2-{64}. synonym: F1. references: Walldorf, Hovemann, and Bautz, 1985, Proc. Nat. Acad. Sci. USA 82: 5795-99. Hovemann, Richter, Walldorf, and Cziepluch, 1988, Nucleic Acids Res. 16: 3175-94. Shepherd, Walldorf, Hug, and Gehring, 1986, Proc. Nat. Acad. Sci. USA 86: 7520-21. phenotype: Encodes an ( unit of the heterotrimeric protein, elongation factor 1, which promotes the binding of aminoacyl- tRNA to ribosomes. Originally isolated on the basis of its displaying 5 to 10 fold overexpression in females versus males. Ef1(1 is expressed throughout development. The rate of protein synthesis in Drosophila declines with age; this has been attributed to impaired binding of aminoacyl-tRNA to ribo- somes, which is promoted by elongation- factor 1 (EF1); tran- scription of elongation factor-1 mRNA shown to decrease with age; by fifteen days following emergence the level of EF1 mRNA is but a few percent that of newly emerged adults (Webster and Webster, 1984, Mech. Ageing Dev. 24: 335-42). Transformation with Ef1(1 under the control of heat shock promoter increased the mean life span from 38.2 to 45.1 days at 25 and from 21.1 to 29.8 days at 29 (Shepherd et al.). cytology: Placed in 48D by in situ hybridization. molecular biology: Investigations of genomic and cDNA clones indicate a gene with 60-base pair untranslated miniexon separated from the main body of the gene by an 1.3-kb intron. The single open reading frame encodes a polypeptide of 463 amino-acids; the sequence is highly conserved; it displays 90% homology with EF1(1 and not much less with EF1( from the brine shrimp and humans, indicating early separation of Ef1(1 and Ef1(2 during the evolution of Drosophila. # Ef1(2 location: 3-{102}. synonym: F2. references: Walldorf, Hovemann, and Bautz, 1985, Proc. Nat. Acad. Sci. USA 82: 5795-99. Hovemann, Richter, Walldorf, and Cziepluch, 1988, Nucleic Acids Res. 16: 3175-94. phenotype: Encodes an ( unit of the heterotrimeric protein, elongation factor 1; isolated by homology with Ef1(1. Expressed primarily in pupae; low levels of mRNA detectable in third-instar larvae and adults. cytology: Placed in 100E by in situ hybridization. molecular biology: Gene comprises five exons separated by introns of 1.24, 0.45, 0.45 and 0.08 kb. Encodes a polypep- tide one amino-acid shorter than that of EF1(1 and 90% homolo- gous thereto. # Ef2 location: 2-{54}. references: Grinblat, Brown, and Kafatos, 1989, Nucleic Acids Res. 17: 7303-14. phenotype: Encodes elongation factor 2 (EF2), which catalyzes the GTP-dependent translocation of tRNA from the aminoacyl to the peptidyl site of the ribosome; also catalyzes hydrolysis of GTP. Expression becomes detectable by four hours of development and persists into adulthood. cytology: Placed in 39E-F by in situ hybridization. molecular biology: Clone selected from embryonic cDNA library probed sequence from mys, which encodes the Drosophila homolo- gue of | integrin, or position specific antigen (PS3); com- parison of the sequence with the published sequences, however, revealed close nucleotide homology with hamster EF2. Longest open reading frame encodes an 844-amino-acid polypeptide of about 95 kd. Shows 85% identity with hamster EF2 except between residues 240 and 274 and between 90 and 100; displays sequence similarity to other GTP binding proteins including EF1(1 in three domains in the N-terminal third, probably involved in GTP binding and GTPase activity; another segment in the N-terminal end and two in the carboxy-terminal end are shared only among elongation factors. The genomic sequence comprises four exons, the first of which is short and largely untranslated; the second contains the GTP-binding domains and one elongation factor specific domain, and the fourth most of the remaining shared domains. Northern blots detect a single mRNA of 3.1 kb. # eg: eagle location: 3-47.3. phenotype: Wings extended. Hairs on thorax somewhat disar- ranged. Dark pattern on thorax. Viability varies among alleles; eg2 females sterile. RK2. alleles: allele origin discoverer ref ( comments _____________________________________________________________________ eg1 Morgan, 1930 1 eg2 Bridges, 33j16 1 eg57c spontaneous Nicoletti, 57c 1, 2 egspy X ray Puro, 1961 3 T(2;3)33D4-E3;79A4-B1 ( 1 = CP627; 2 = Nicoletti, 1957, DIS 31: 84; 3 = Puro and Arajarvi, 1969, Hereditas 62: 414-18. cytology: Placed in 79A4-B1 based on the third-chromosome breakpoint of T(2;3)egspy = T(2;3)33D4-E3;79A4-B1. # egalitarian: see egl # Egfr: Epidermal growth factor receptor homologue location: 2-100. synonym: C-erb; DER. references: Livneh, Glazer, Segal, Schlessinger, and Shilo, 1985, Cell 40: 599-607. Wadsworth, Vincent, and Bilodeau-Wentworth, 1985, Nature 314: 178-80. Lev, Shilo, and Kimchie, 1985, Dev. Biol. 110: 499-502. Schejter, Segal, Glazer, and Shilo, 1986, Cell 46: 1091-1101. Price, Clifford, and Schupbach, 1989, Cell 56: 1085-92. Schejter and Shilo, 1989, Cell 56: 1093-1104. phenotype: Encodes the Drosophila homolog of epidermal growth factor receptor protein. Mutations with three different phenotypes and described under three different names shown to be alleles of Egfr. Elp (Ellipse) is a dominant eye shape and texture mutant; flb (faint little ball) is an embryonic lethal causing dorsalized embryos, and top (torpedo) is a maternal- effect lethal causing ventralized embryos; each of these classes is described in detail at the end of the entry; in situ hybridization with transcript-specific probes reveals uniform distribution of transcript during embryogenesis; in larvae, hybridization confined to mitotic tissues and not seen in cells with polytene chromosomes (Kammermeyer and Wadsworth, 1987, Development 100: 201-10). Transcript concentrated in cells of the central nervous system and gonial cells in adults. alleles: Price et al. have subsumed the embryonic lethal alleles (flb) under the symbol for the maternal-effect-lethal alleles (top). We further consolidate both along with the dominant visible alleles (Elp) under the symbol Egfr as Egfrf, Egfrt, and EgfrE alleles respectively. allele origin synonym ref ( comments ________________________________________________________________ EgfrE1 spont Elp1 2, 3 hypermorph *EgfrE2 X ray Elp2 1 T(Y;2)57C9-D5 EgfrE3 EMS ElpB1 2 hypermorph Egfrf1 EMS flb1F26 4, 7 weak allele Egfrf2 EMS flb1K35 4, 7 severe allele Egfrf3 EMS flb1P02 4, 7 severe allele Egfrf4 EMS flb2C82 4, 7 intermediate allele Egfrf5 EMS flb2G31 4, 7 severe allele Egfrf6 EMS flb2L65 4, 7 severe allele Egfrf7 EMS flb2W74 4, 7 weak allele Egfrf8 EMS flb2X51 4, 7 severe allele Egfrf9 EMS flb3B41 4, 7 severe allele Egfrf10 EMS flb3B92 4, 7 severe allele Egfrf11 EMS flb3C81 4, 7 severe allele Egfrf12 EMS flb3C87 4, 7 severe allele Egfrf13 EMS flb3E07 4, 7 weak allele Egfrf14 EMS l(2)57DEFa1 5, 7 severe allele Egfrf15 EMS l(2)57DEFa2 5, 7 severe allele Egfrf16 EMS l(2)57DEFa3 5 Egfrf17 EMS l(2)57DEFa4 5, 7 weak allele Egfrf18 EMS l(2)ES3 7 weak allele Egfrf19 EMS l(2)ES6 7 weak allele Egfrf20 EMS l(2)ES18 7 weak allele Egfrf21 EMS l(2)ES45 7 intermediate allele Egfrf22 EMS l(2)JE3 7 weak allele Egfrf23 EMS l(2)SH3 7 weak allele Egfrf24 EMS topCO 6 Egfrf25 EMS 6 Egfrf26 EMS 6 Egfrf27 EMS 6 Egfrf28 EMS 6 Egfrf29 EMS 6 Egfrf30 EMS 6 Egfrf31 EMS 6 Egfrf32 EMS 6 Egfrf33 EMS 6 Egfrf34 EMS 6 Egfrf35 EMS 6 Egfrf36 / ray top10B 6 In(2R)57A;57F Egfrf37 / ray top4A 6 Egfrf38 / ray top21B 6 Egfrf39 EMS ElpB1RB2 2 Elp2 revertant Egfrf40 EMS ElpB1RB3 2 Elp2 revertant Egfrf41 EMS ElpB1RB4 2 Elp2 revertant Egfrf42 EMS ElpB1RB5 2 Elp2 revertant Egfrf43 x ray ElpRE124 2 Elp1 revertant Egfrt1 EMS topQY 6, 7 maternal-effect lethal Egfrt2 EMS topCJ 6 maternal-effect lethal ( 1 = Ashburner, Faithfull, Littlewood, Richards, Smith, Vel- issariou, and Woodruff, 1980, DIS 55: 193-95; 2 = Baker and Rubin, 1989, Nature (London) 150-53 (fig.); 3 = Grell, 1960, DIS 34: 50; 4 = Nusslein-Volhard, Wieschaus, and Kluding, 1984, Wilhelm Roux's Arch. Dev. Biol. 193: 267-83; 5 = O'Donnell, Boswell, Reynolds, and Mackay, 1989, Genetics 121: 273-80; 6 = Price, Clifford and Schupbach, 1989, Cell 56: 1085-92; 7 = Schejter and Shilo, 1989, Cell 56: 1093- 1104. cytology: Genomic clone hybridizes to 57F. molecular biology: Genomic sequence isolated using a probe homologous to kinase domain of the v-erbB oncogene protein. cDNA clones isolated from 3-12 hr cDNA library. Sequence com- parisons of cDNA and genomic clones reveal the presence of four 3 exons separated by three small introns; these are separated from two distant 5 exons by a long (i.e., 45 kb) intron. Three different splicing patterns in the 5 region each associated with a different 3 polyadenylation site gen- erate three different transcripts. Conceptual amino-acid sequence suggests a 42-base-pair signal sequence followed by a 769-nucleotide extracelluar putative EGF-binding domain with twelve potential N-linked glycosylation sites and 68 cystein residues, a 31-residue hydrophobic transmembrane region, and a 566-nucleotide cytoplasmic kinase domain with but 13 cys- teines. The overall amino-acid homology with human epidermal-growth-factor receptor is 41% in the extracellular domain and 55% in the kinase domain. The ligand-binding domain contains three cysteine-rich regions, which share homology with each other and with two such regions present in human EGF receptor. # EgfrE synonym: Elp: Ellipse references: Grell, 1960, DIS 34: 50. Baker and Rubin, 1989, Nature (London) 150-53 (fig.). phenotype: Eyes of EgfrE/+ heterozygotes rough and more oval than wild type; also display a slight disturbance of the wing-vein pattern. Homozygotes have smaller eyes with many fewer ommatidia and some regions lack them entirely; those ommatidia that are formed contain the normal number and arrangement of cells; the regions without ommatidia contain cells that resemble pigment cells and mechanosensory bristles; only about one tenth the normal number of preommatidial cell clusters differentiate behind the morphogenetic furrow. EgfrE in heterozygous combination with a deficiency or null mutation for Egfr is normal in phenotype indicating that EgfrE alleles are hypermorphic. # Egfrf synonym: flb: faint little ball origin: Recovered as embryonic lethals (Egfrf1 to Egfrf23) as mutations that fail to complement the female sterile effect (Egfrf24 to Egfrf35) or the wing-vein defect (Egfrf36 to Egfrf38) of Egfrt or, as revertants of EgfrE (Egfrf39 to Egfrf43). references: Nusslein-Volhard, Wieschaus and Kluding, 1984, Wilhelm Roux's Arch. Dev. Biol. 193: 267-83. Schejter and Shilo, 1989, Cell 56: 1093-1104. Tearle and Nusslein-Volhard, 1987, DIS 66: 209-26. phenotype: Embryonic lethal. Embryos form a ball of dorsal hypoderm with the internal organs extruded anteriorly. Ven- tral cuticle absent or strongly reduced. First visible in extended-germ-band stage. Cells at the anterior and posterior ends of the embryo form clumps and slough off; very few head and gnathal cells remain. Substantial ectodermal cell death observed; germ band retraction fails to take place. Ulti- mately, cuticle formation produces mostly dorsal and lateral cuticular elements with but a narrow strip of denticles mid- ventrally. Hypomorphic alleles initiate but do not complete germ-band retraction; they show intermediate phenotypes with wider denticle bands and in weak alleles some head and telson structures are formed as well. No maternal effect as shown by pole-cell transplantation. # Egfrt synonym: top: torpedo. references: Schupbach, 1987, Cell 49: 699-707. Price, Clifford and Schupbach, 1989, Cell 56: 1085-92. phenotype: Maternal-effect lethal. Homozygous females lay eggs that are long and pointed at both ends. Such eggs often have only one fused dorsal appendage; also there is an increase in the number of follicle cells that give rise to the main body of the chorion at the expense of those ordinarily contributing to the operculum and dorsal appendages. Egfrt alleles are completely recessive and fully penetrant in homozygous females; the embryos never hatch. Homozygous and hemizygous adult flies exhibit incomplete fourth veins, absence of the anterior crossvein, rough eyes, loss of ocelli and ocellar bristles, and the loss of sensory bristles from the thorax. Changes in the embryonic pattern become visible at the begin- ning of gastrulation. Around the circumference of the embryo, 40% of the cells invaginate on the ventral side and form meso- derm; these cells become organized into two ventral furrows which are lost in later stages, and a mass of mesodermal cells fills the ventral half of the embryo. The only cuticle struc- ture differentiated is a strip of dorsal hypoderm flanked by bands of ventral setae; lateral and ventral sides are made up of mesoderm. The head is reduced but filzkorper and spiracles are visible posteriorly. Experiments with germline mosaics produced by pole cell transplantation indicate that the mutant gives rise to ventralized eggs and embryos by interferring with processes taking place in somatic cells rather than ger- minal tissue. The mutant phenotype was only produced in mosa- ics in which wild-type germ cells were surrounded by Egfrt follicle cells and not by the reverse cell arrangement. Egfrt blocks dorsalization caused by fs(1)K10, but not that produced by dl females. # egl: egalitarian (T. Schupbach) location: 2-105. origin: Induced by ethyl methanesulfonate. references: Schupbach and Wieschaus. phenotype: Female sterile. Defect in cell fate detectable in anterior germarium. In contrast to wild-type, in all egl alleles all sixteen cells per cyst enter pachytene; subse- quently all sixteen revert to nurse-cell morphology and behavior (Carpenter). Egg chambers increase in volume along the ovariole, but do not take up yolk. No chorion is formed. BicD/+ females simultaneously heterozygous for egl1 or egl2 fail to form double-abdomen embryos (Mohler and Wieschaus, 1986, Genetics 112: 803-22). alleles: Five alleles; egl1 through egl5, originally isolated as WU, RC, PB, Pr, and PV, respectively. cytology: Placed in 59D8-60A2, since uncovered by Df(2R)bw-S46 = Df(2R)59D8-11;60A7, and by Df(2R)bw-D23 = Df(2R)59D4- 5;60A1-2. # Egon: Embryonic gonad location: 3-{47}. origin: Isolated from genomic library using a kni zinc-finger probe. references: Rothe, Nauber, and Jackle, 1989, EMBO J. 8: 3087- 89. phenotype: Expression detected in embryonic gonad but not in other tissues or at other stages of development. cytology: Placed in 79B by in situ hybridization. molecular biology: Nucleotide sequence indicates an open read- ing frame encoding a polypeptide of 373 amino acids with a 1421-nucleotide intron between codons 26 and 27. The first 90 amino acids, which contain the zinc-finger domain, show 80% and 86% similarity to the products of kni and knrl, respec- tively; the three proteins share a 19-amino-acid motif, the kni box, just downstream from the zinc-finger domain. These polypeptides share features with vertebrate steroid hormone receptors; their putative ligand-binding domains exhibit a low level of similarity. # Eip55BD: Ecdysteroid-inducible polypeptide encoded in 55BD location: 2- {86}. synonym: Eip40. references: Cherbas, Cherbas, Savakis, and Koehler, 1981, Am. Zool. 21: 743-50. phenotype: The structural gene for a 40 kilodalton polypeptide (EIP40) whose concentration in Kc cells increases detectably beginning 30-60 min following administration of ecdysteroid hormone and reaching a maximum after 4-6 hr (Savakis, Demetri, and Cherbas, 1980, Cell 22: 665-74). molecular biology: cDNA clone pKc252 isolated and used to select genomic clones from Maniatis library. cytology: In situ hybridization localizes sequence to 55B-D. # Eip71CD synonym: Eip28/29. location: 3-{42}. references: Cherbas, Cherbas, Savakis, and Koehler, 1981, Am. Zool. 21: 743-50. Savakis, Koehler, and Cherbas, 1984, EMBO J. 3: 235-43. Cherbas, Schulz, Koehler, Savakis, and Cherbas, 1986, J. Mol. Biol. 189: 617-31. Schulz, Cherbas, and Cherbas, 1986, Proc. Nat. Acad. Sci. USA 83: 9428-32. phenotype: The structural gene for 28 and 29 kilodalton (as determined by gel mobility) polypeptides (EIP28, EIP29) whose concentration in Kc cells increases detectably beginning at 30-60 min and reaches a maximum at 4-6 hr following ecdys- teroid administration (Savakis, Demetri, and Cherbas, 1980, Cell 22: 665-74). Each protein exists in three isoforms with different pI's, possibly owing to acetylation. molecular biology: cDNA clone pKC252 isolated and used to select genomic clones. Hybrid selected mRNA translation pro- ducts include both EIP28 and EIP29. Sequence analysis reveals the presence of four exons, `, (, |, and / from 11743 to -1627, -628 (or -640) to -435, -324 to -64, and -4 to + 406 respectively. All contain coding information. Two primary transcripts are produced by alternate splicing; 75% use the consensus splice donor sequence of exon ( and 25% an alternate donor site twelve bases upstream, encoding a polypeptide internally deleted for four amino acids: Tyr Lys Arg Met. Since EIP28 is two charges more basic than EIP29, it is con- cluded to be encoded by the longer message, which specifies a conceptual sequence of 28,218 Daltons, and EIP29 is encoded by the shorter message producing a product of 27,640 Daltons. cytology: In situ hybridization localizes sequence to 71C3-D2. # Eip74EF: see E74 # Eip75: see E75 el: elbow From Bridges and Brehme, 1944, Carnegie Inst. Washington Publ. No. 552: 75. # el: elbow (M. Ashburner) location: 2-50.0. discoverer: E. M. Wallace, 35d1. references: Bridges and Brehme, 1944. phenotype: Wings extended and bent backward, often warped and shortened; sometimes blistered and nicked. Alulae reduced in size with reduced number of marginal bristles-may fuse with wing blade. Venation reduced by terminal shortening of L5 and of crossveins. Halteres reduced, often to stubs. Eye size decreased (variable, even with strong alleles). Weak alleles may overlap wild type and show only a reduction in number of marginal bristles on alulae. Some alleles may be semilethal when hemizygous. Class (i) alleles enhance Sco, are sem- ilethal with alleles of l(2)35Ba and show a weak noc phenotype when heterozygous with strong noc alleles or noc deletions. Class (ii) alleles do not interact with these loci. All alleles more extreme when hemizygous; strong alleles nearly apterous. allele origin discoverer ref ( comments ___________________________________________________________________ el1 spont E. Wallace, 35d1 4 strong; class i el2 | EMS Maroni 3 weak; class i el3 / EMS 2, 5 weak; class i el4 EMS Harrington 1 strong; class ii el5 X ray intermediate; class ii el6 EMS Angel, 82f2 class ii el7 / ray Ashburner T(2;3)shv19 el8 / ray Johnson el9 / ray Johnson In(2L)34A2-3;35A3-4 el10 / ray Johnson el11 / ray Johnson el12 / ray Johnson el13 / ray Johnson el14 / ray Johnson el21 EMS Johnson el22 EMS Johnson el23 EMS Johnson ( 1 = Ashburner, Angel, Detwiler, Faithfull, Gubb, Harrington, Littlewood, Tsubota, Velissariou, and Walker, 1981, DIS 56: 186; 2 = Ashburner, Faithfull, Littlewood, Richards, Smith, Velissariou, and Woodruff, 1980, DIS 55: 193-95; 3 = Ash- burner, Tsubota, and Woodruff, 1982, Genetics 102: 401-20; 4 = CP627; 5 = Woodruff and Ashburner, 1979, Genetics 92: 133-49. | Formerly elGM2; to the right of el1; 0.02% recombination (Maroni); partially complements el1; hemizygotes show weak expression; homozygotes exhibit < 0.5% viability. / Temperature-sensitive allele; partially complements el1 at 25 but not at 29. cytology: Placed in region 35A1-3 on the basis of its inclusion in Df(2L)fn2 = Df(2L)35A1-3;35B2-4 but not in Df(2L)fn3 = Df(2L)35B1;35B3-4 or Df(2L)b80e3 = Df(2L)34C3-4;35A4-B1. el4 associated with T(Y;2)el4; breakpoint distal to el. el5 asso- ciated with T(Y;2)A15. other information: Part of el-noc complex. # elav: embryonic lethal, abnormal vision (J. C. Hall) location: 1-{0}. synonym: l(1)EC7, fliJ, l(1)Bg. references: Homyk, Szidonya, and Suzuki, 1980, Mol. Gen. Genet. 177: 553-65. Homyk and Grigliatti, 1983, Dev. Genet. 4: 77-97. Campos, Grossman, and White, 1985, J. Neurogenet. 2: 197-218. Homyk, Isono and Pak, 1985, J. Neurogenet. 2: 309-24. Campos, Rosen, Robinow and White, 1987, EMBO J. 6: 425-31. Jimenez and Campos-Ortega, 1987, J. Neurogenet. 4: 179-200. Robinow, Campos, Yao and White, 1988, Science 242: 1570-72. Robinow and White, 1988, Dev. Biol. 126: 294-303. phenotype: Embryonic lethal, or in the case of viable and ostensibly hypomorphic alleles, displays poor jumping and fly- ing ability plus aberrant visual physiology and behavior. No morphological abnormalities visible in sections of dying embryos (elav1, elav2, or elav3); however, whole-mount embryos show periodic interruptions in the longitudinal connectives of the CNS and missing commissures especially the posterior ones (Jimenez and Campos-Ortega). elavts1 allows survival to adult stage at 19-25 but viability is reduced and adults usually die soon after eclosion; viability after rearing at 30 is very low and newly emerged adults show poor coordination and die soon; this temperature-sensitive allele also causes morphological abnormalities in the brain, especially in the visual system (after postembryonic shift from 19 to 30 or even following all development at low-temperature); optic chiasma is abnormal and second order optic lobe (medulla) is rotated to aberrant posi- tion (Campos et al., 1985); when elavts1 raised at 30, surface of eye is rough and photoreceptor layer abnormal in sections (Campos et al., 1985). Another temperature-sensitive allele elav19 also induces abnormalities of visual system (Homyk et al., 1985); rearing at 29 or high-temperature pulses delivered to pupae, raised otherwise at 20, causes vacuolization of pho- toreceptors and disorganization of rhabdomeres; high- temperature rearing or pupal pulsing induces severe optic lobe defects (absence of size reduction); electroretinograms of this mutant, raised at high-temperature, are missing light-on and light-off transient spikes (also seen after low- temperature rearing) and have reduction of ERG photoreceptor potential; amplitude of this potential also deteriorates as does deep pseudopupil when adults treated at high-temperature after low-temperature rearing; mosaic analysis (Campos et al., 1985) of elav1 reveals autonomously induced defects in eye morphology, but no effects on other imaginal disc derivatives, and suggests both directly induced defects in optic lobe development, as well as inductively caused CNS defects medi- ated through expression of this mutation in the eye (i. e., such that the visual system's ganglia are genotypically nor- mal). Lethal "focusing" in these mosaics suggests influence of gene on derivatives of ventral blastoderm. In studies of viable alleles, elav19 and elav20, both of which are temperature-sensitive, flying and jumping ability shown to be especially aberrant after rearing at 29; wing position also aberrant; elavts1 most severe, including having no optomotor response when raised at high (or even low) temperature; temperature-sensitive period for aberrant wing posture in elav19 extends from larval to pupal period (Homyk and Grigli- atti). An antibody specific to neuronal nuclei fails to stain neurons of elav-deficient embryos; however, the quantity of antigen does not respond to the number of elav+ genes present (Bier, Ackerman, Barbel, Jan and Jan, 1988, Science 240: 913-16). elav transcripts detected in all postmitotic neurons, from their birth; not seen in embryonic or larval neuroblasts. Also seen in larval eye discs, adult retinas and Johnston's organ of the antennae. alleles: allele origin discoverer synonym ref ( comments ___________________________________________________________________ elav1 EMS White 1 elav2 MMS Lim l(1)EC7M3 1 elav3 MMS Lim l(1)EC7M11 elav4 X ray Lefevre l(1)A74 4 In(1)1A6-B1;1B5-9 l(1)EC7G3 elavG3 elav5 X ray Lefevre l(1)A138 4 elav6 X ray Lefevre l(1)N78 4 *elav7 X ray Lefevre l(1)RF57 4 l(1)EC7G10 *elav8 EMS Lefevre l(1)EF435 5, 6 embryonic lethal no maternal effect elav9 EMS Lefevre l(1)VA18 5 elav10 EMS Lefevre l(1)VA21 5 elav11 EMS Lefevre l(1)VA262 5 elav12 EMS White elavMM3 leaky elav13 ENU Voelker l(1)A34 elav14 ENU Voelker l(1)A54 elav15 ENU Voelker l(1)A75 elav16 ENU Voelker l(1)A129 elav17 HMS l(1)HM30 3 elav18 HMS l(1)HM41 3 elav19 EMS Homyk fliJ1 2 temperature sensitive elav20 EMS Homyk fliJ2 2 temperature sensitive elav21 EMS Rosen elavA34 elav22 EMS Rosen elavA54 elav23 EMS Rosen elavA75 elav24 EMS Rosen elavA129 elavts1 EMS White temperature sensitive ( 1 = Campos, Grossman, and White, l985, J. Neurogenet. 2: 197-218; 2 = Homyk, Szidonya, and Suzuki, 1980, Mol. Gen. Genet. 177: 553-65; 3 = Kramers, Schalet, Paradi, and Huiser-Hoogteyling, 1983 , Mutat. Res. 107: 187-201; 4 = Lefevre, l981, Genetics 99: 461-80; 5 = Lefevre and Wat- kins, 1986, Genetics 113: 869-95; 6 = Perrimon, Engstrom, and Mahowald, 1984, Dev. Biol. 105: 404-14. cytology: Placed in 1B5-9 based on the proximal breakpoint of In(1)elav4 = In(1)1A6-B1;1B5-9, which interrupts the elav gene. molecular biology: Probing Northern blots with a 4.8-kb genomic subclone spanning the In(1)elav4 breakpoint identifies 4.7, 5.4, and 6.1-kb transcripts; the 5.4-kb RNA is seen in 0-6-hr embryos and the 4.7 and 6.1-kb RNAs in 6-18-hr embryos; no transcripts seen in larvae and two very low abundance RNAs of similar size to the embryonic RNAs seen in pupae; adult heads contain 5.4 and 6.1-kb transcripts; all three transcribed from right to left. A genomic clone encompassing the region homo- logous to the 4.7 and 6.1 but not all of the 5.4-kb transcript able to rescue lethality of elav. Sequence analysis of genomic and partial-length cDNA clones indicate an open read- ing frame specifying a complete polypeptide of 483 amino acids and 50.76 kd. The coding sequence contains two introns of 1289 and 2208 nucleotides. The conceptual translation product con- tains three repeats of a pair of sequences previously defined as RNA-binding consensus sequences, an octopeptide, RNP1, and an appropriately spaced hexapeptide, RNP2, suggesting that this protein is involved in the RNA metabolism of neurons. In addition, a palindromic sequence is seen 5 to the transcrip- tion unit and GAGA motifs are found 5 to the transcription unit, and in the second intron. Eleven copies of a putative zeste-protein-binding sequence are found in the vicinity. # elbow: see el # elf: extra lamina fiber (J.C. Hall) location: 1- between v and f. origin: Induced by ethyl methanesulfonate. synonym: H37; opm37. references: Heisenberg and Gotz, 1975, J. Comp. Physiol. 117: 127-62. phenotype: An extra large fiber profile is found in each car- tridge of lamina (first order optic lobe); adults exhibit defective phototaxis and optomotor responses (e.g., higher than normal light intensities needed for vigorous responses); light-off transient spike of electroretinogram weak. other information: Morphological difference from normal may no longer exist in adult lamina (Meinertzhagen). # elfin: see ef # Elf-1: see Ntf # Ellipse: see EgfrE # ellipsoid body open: see ebo # elliptical rough: see elr # Elongation factor: see Ef # Elp: see EgfrE #*elr: elliptical rough location: 1-25.1. origin: X ray induced. discoverer: Fahmy, 1956. references: 1960, DIS 34: 49. phenotype: Eyes slightly elliptical and rough. Wings slightly broader. Both sexes viable and fertile. RK2. other information: Two other alleles: one induced by X rays, one by L-p-N, N-di-(2-chloroethyl)amino-phenylalanine. # elyC: early C location: 3-(unmapped). origin: Induced by ethyl methanesulfonate. discoverer: Nusslein-Volhard. references: Tearle and Nusslein-Volhard, 1987, DIS 66: 209-26. phenotype: Maternal-effect lethal. Embryos produced by homozy- gous females show abnormal development during early cleavage and cease development soon thereafter. alleles: Two, elyC1 and elyC2, isolated as 043 and 230. # Embryonic gonad: see Egon # embryonic lethal, abnormal vision: see elav # emc: extra machrochaetae (H.M. Ellis) location: 3-0. references: Botas, Moscoso del Prado, and Garcia-Bellido, 1982, EMBO J. 1: 307-10. Moscoso del Prado and Garcia-Bellido, 1984, Wilhelm Roux's Arch. Dev. Biol. 193: 242-45. Garcia-Alonso and Garcia-Bellido, 1988, Roux's Arch. Dev. Biol. 197: 328-38. Ellis, Spann, and Posakony, 1990, Cell 61: 27-38. Garrell and Modolell, 1990, Cell 61: 39-48. phenotype: Hypomorphic alleles, or amorphic alleles when heterozygous with a hypomorphic allele, cause formation of extra macrochaetae. Severely hypomorphic combinations also cause formation of extra microchaetae. Amorphic alleles when homozygous result in embryonic lethality. Amorphic alleles when heterozygous with a normal third chromosome result in the appearance of ectopic chaetae in the occipital and premandibu- lar regions. Extra chaetae in emc mutant flies appear on the head and notum (weak alleles) as well as on the wing blade, pleura, post-scutellum, tergites and legs in more severe allelic combinations. In severely hypomorphic allelic combi- nations extra campaniform sensilla occasionally appear on the wing blade. Reduction of wild-type emc function also causes the presence of extra bits of wing vein. A dominant emc allele (emcD) causes a reduction in the number of macrochaetae on the head and notum. emcD is homozygous viable; emcD homozygotes are more mutant than emcD/+ individuals. The L4 and L5 wing veins are shortened in emcD homozygotes but only rarely in emcD/+ heterozygotes. The insufficiency produced by emc can be titrated by altering the dosage of ASC; increased function of ASC produced by gain-of-function mutations (Hw) can be titrated by altering the dosage of emc+. alleles: allele origin discoverer synonym ref ( comments | __________________________________________________________________________ emc1 EMS Ripoll 1 lethal; cytology normal emc2 1 in TM2 emc3 X ray Moscoso del Prado AN88 5 T(Y;3)61C4-9 emc4 X ray Moscoso del Prado BB83 4, 5 In(3L)61C-D;61E-F emc5 X ray Moscoso del Prado CC92 4, 5 In(3L)61C;61C emc6 X ray Moscoso del Prado DT99 4, 5 T(2;3)34D;61C4-D emc7 X ray Moscoso del Prado DO96 5 cytology normal emc8 X ray Moscoso del Prado ES106 5 T(2;3)47A;61C4-D emc9 X ray Moscoso del Prado FX119 4, 5 lethal; cytology normal emc10 X ray Moscoso del Prado R14 5 In(3L)61C3-8;80F emc11 X ray Rubio emcpel 4 viable; cytology normal emc12 X ray Ellis 9-5a lethal; T(2;3)52;61C emc15 X ray Ellis 13-16 viable; In(3L)61C;64;? emc16 X ray Ellis 17-2A lethal; In(3L)61C5-6;80F emc17 X ray Ellis 20-1A viable; In(3L)61C;62C emc18 / X ray Ellis 24-4a viable; cytology normal emc19 X ray Ellis 29-2 viable; T(2;3)5B5-9;61C4 emc20 EMS Spann emcM7 viable; cytology normal emc21 EMS Leviten emcM1 lethal; cytology normal emc22 ` X ray Ellis Ar5-5 lethal; cytology normal emc23 P - Ellis emcP3 3 lethal; P insert at 61D1-2 emc24 P Ellis emcP4 3 viable; P insert at 61D1-2 emc25 P Ellis emcP6 3 viable; P insert at 61D1-2 emc26 P Ellis emcP7 3 lethal; P insert at 61D1-2 emc27 P Ellis emcP15 3 viable; P insert at 61D1-2 emc28 P Ellis emcP16 3 viable; P insert at 61D1-2 emc29 P Ellis emcP17 3 viable; P insert at 61D1-2 emc30 P Ellis emcP24 3 viable; P insert at 61D1-2 emc31 P Ellis emcP25 3 lethal; P insert at 61D1-2 emc32 P Ellis emcP26 3 viable; P insert at 61D1-2 emc33 ` P Ellis AP1-3a viable; P insert at 61D1-2 emc34 ` P Ellis AP3-6 lethal; P insert at 61D1-2 emcD spont Craymer Ach 2 viable; cytology normal ( 1 = Botas, Moscoso del Prado, and Garcia-Bellido, 1982, EMBO J. 1: 307-10; 2 = Craymer, 1980, DIS 55: 197-200; 3 = Ellis, Spann, and Posakony, 1990, Cell 61: 27-38; 4 = Garcia-Alonso and Garcia-Bellido, 1988, Roux's Arch. Dev. Biol. 197: 328-38; 5 = Moscoso del Prado, 1985, PhD thesis, Universidad Autonoma de Madrid. | Viability refers to homozygotes. / Hypomorphic allele; complements amorphic alleles for lethal- ity. ` emcD revertant. - These experiments utilized Birmingham 2; delta 2-3. cytology: Placed in 61D1-2 on the basis of in situ hybridiza- tion with P-element probes to revertible P-element induced emc null alleles. molecular biology: The emc locus encodes a 2.3-kb transcript (interrupted by a single intron of 1.9-kb) that is present at all stages of development. Peak levels of transcript accumu- lation occur in 6-16 hour embryos and late third instar larvae and early pupae. emc transcripts appear in ovaries as well as female somatic tissue. Transcripts are also present in adult males. emc transcripts are present throughout the embryo at all stages from early cleavage through germ band extension. In third-instar larvae, emc transcripts are found in all tissues but are more abundant in the imaginal discs. RNA distribution is relatively homogeneous throughout the wing disc. emc cDNA clones contain a single long open reading frame capable of encoding a protein of approximately 22 kd. Analysis of the derived sequence of the emc protein shows that it is a member of the helix-loop-helix (HLH) family of proteins, but lacks the DNA binding motif characteristic of this group of pro- teins. # ems: empty spiracles location: 3-53. origin: Induced by ethyl methanesulfonate. references: Jurgens, Wieschaus, Nusslein-Volhard, and Kluding, 1984, Wilhelm Roux's Arch. Dev. Biol. 193: 283-95 (fig.). Dalton, Chadwick, and McGinnis, 1989, Genes Dev. 3: 1940-56 (fig.). phenotype: Embryonic lethal. Embryos display loss of filzorper in the posterior spiracles; posterior ends of longitudinal tracheal trunks incomplete. Failure of head involution; many cuticular structures that normally derive from the procephalic and mandibular lobes of the head missing; embryonic antennal organs missing. ems protein first appears as an anterior ring around the syncytial blastoderm at a position just anterior to that of Dfd; it is five to six cells wide dorsally and 10-12 cells wide ventrally; at gastrulation the ring is just ante- rior to the cephalic furrow. As gastrulation proceeds expres- sion becomes patchy and confined to specific groups of cells. The protein is nuclear in localization. The metameric pattern of ems expression commences at the beginning of germ-band extension; protein first appears in a group of cells in each segment, which subsequently elongates and splits into two clusters of ems-positive cells in regions destined to give rise to tracheal pits, neuroblasts and epidermis. In the eighth abdominal segment, a large patch of ems-positive cells forms just posterior to the tracheal pit and presumably correspond to the primordia of the posterior spiracles and the filzkorper; a similar patch is formed anteriorly in embryos produced by bcd mothers. For a detailed discussion of the expression pattern see Dalton et al.. alleles: Five alleles induced with ethyl methanesulfonate by Jurgens et al.. allele synonym comments ______________________________________________ ems1 7D99 ems2 9H83 amorphic allele; stop codon at residue161 ems3 9Q64 stop codon at residue141 ems4 10A hypomorphic allele cytology: Placed in 88A1-2 by in situ hybridization. molecular biology: Gene isolated on basis of homology to eve homeo domain. Northern blots with genomic fragment detect a 2.3-kb transcript that reaches peak abundance during 6-12 hr of embryonic development, and with substantial expression throughout embryonic development as well as in the third lar- val instar and pupal stages. Nucleotide sequence of a 2.2-kb cDNA and a portion of genomic sequence reveals the presence of an ~300 nucleotide intron just upstream of the homeo domain. The longest open reading frame could encode a polypeptide of 494 amino-acid residues; amino acids 1-384 contain 80 proline residues; residues 99-359 contain 12% glutamines. The C- terminal end contains a 24-amino-acid segment with 62% glu- tamic and aspartic acid residues. The homeo-domain sequence is quite divergent from other published homeobox sequences, exhi- biting less than 50% identity. en: engrailed From Eker, 1929, Hereditas 12: 217-22.