See Weeks, et al., Genes & Development Vol 7,  Dec 1993 for more
details.



Figure 3.  Distinct Distributions of Pol IIA and II0 on Polytene
Chromosomes.
Formaldehyde-fixed chromosome preparation reacted with goat anti-CTD
("anti-IIA") and rabbit anti-PCTD ("anti-II0") antibodies and visualized
by indirect immunofluorescence and digital imaging (see Materials and
Methods).  This overlay of anti-CTD (green) and anti-PCTD (red) images
shows principally the distal half of the X chromosome.  Arrows indicate
examples of not obviously puffed red (up arrow), green (left arrow) and
mixed (down arrow) signals.  2B5 indicates an early ecdysone-induced puff.
 Bar represents 5 mm.


Figure 4.  RNA Pol II0 and IIA on Major Ecdysone Puffs.  
Distal three fourths of chromosome 3L from a preparation reacted with goat
anti-IIA and rabbit anti-II0 antibodies.

(a)  Anti-IIA signal.

(b)  Anti-II0 signal.

(c)  Overlay of a and b.  Major early ecdysone puffs at 74EF and 75B
("Chinese lanterns") are indicated, as are examples of not obviously
puffed sites that stain red (up arrow), green (left arrow) and mixed (down
arrow).


Figure 5.  RNA Pol IIA and II0 on Heat Shock Puffs.
(a)  A chromosome preparation from a wildtype larva heat shocked for ca.
20 min at 37¡C was reacted with goat anti-IIA (green) and rabbit anti-II0
(red) antibodies; overlay shown.  Major heat shock puffs are labeled.
(b)  Goat anti-IIA (green) and rabbit anti-II0 (red) staining of
chromosomes from transformant Bg9,61 larva heat shocked ca. 5 min at 37¡C.
 Overlay image.  Puffs at insertion sites near 9E and 61A are indicated.



Figure 6.  Staining Patterns at hsp70-lacZ Transgene Sites without  Heat
Shock.  

(a),(a'):  DAPI-stained sections of chromosomes showing regions around
transposon insertion sites near 9E and 61A; images reversed to mimic
classical banding pattern (most intense fluorescence appears darkest). 
Several prominent bands are indicated.

(b),(b'):  Goat anti-IIA (green) and rabbit anti-II0 (red) staining of
non-heat shock wild type preparations.  Overlay images. 

(c),(c'):  Goat anti-IIA (green) and rabbit anti-II0 (red) staining of
non-heat shock transformant Bg9,61 preparations.  Overlay images.  In (c),
arrow labeled 9E points at novel green fluorescence signal present in
transformant chromosomes.  In (c'), arrow labeled  t points at novel green
fluorescence signal present in transformant chromosomes.



Figure 7.  Pol IIA and Heat Shock Factor at hsp70-lacZ Transgene Sites
after Heat Shock.
Rabbit anti-HSF (red) and goat anti-IIA (green) staining of chromosomes
from wild type and transformant Bg9,61 salivary glands.

(a),(a'):  Wildtype salivary glands heat shocked in 37¡C buffer ca. 90
sec.  Arrows labeled 9E and t point at sites in regions 9E and 61A,
respectively, that lack fluorescence signals.

(b),(b'):  Transformant Bg9,61 salivary glands heat shocked in 37¡C buffer
ca. 90 sec.  Arrows labeled 9E and t point at sites of
transposon-dependent fluorescence signals in regions 9E and 61A,
respectively.

(c),(c'):  Transformant larva heat shocked 5 min; chromosomes stained with
goat anti-IIA.  Arrows 9E and t indicate point at more intense signal near
one edge of the induced transgene-dependent heat shock puffs in regions 9E
and 61A, respectively.

(d),(d'):  Same preparations as in (c) and (c'), stained with rabbit
anti-HSF.  Arrows as in (c, c').  

(e),(e'):  Overlay of images in (c, d) and (c', d'), respectively.  Bar in
(e) represents 5 mm.


Figure 8.  HnRNP Proteins Preferentially Co-localize with Pol II0.
Non heat shock preparations were double labeled with mouse monoclonal
antibodies to Drosophila hrp36 + hrp48 (red) and either (a) rabbit
anti-II0 (green) or (b) goat anti-IIA (green).  Overlay images.



Figure 9.  A Splicing Component Preferentially Co-localizes with Pol II0.
Non heat shock preparations were double labeled with a mouse monoclonal
antibody to U1 snRNP 70k protein (red) and either (a) rabbit anti-II0
(green) or (b) goat anti-IIA (green).  In (b), examples of red signals
(down arrows) and a green signal (up arrow) are indicated.  Overlay
images.