XB-IMG-136052
Xenbase Image ID: 136052
|
Figure 2. Ectopic expression of MyoD proteins activates RSRF
gene transcription in animal pole explants. Fertilized eggs were
injected with RSRF and myogenic factor RNAs, cultured until
blastula stage, and dissected to obtain animal pole explants.
These were cultured until mid-late neurula stage and analyzed
by RNase protection assay for the presence of cardiac actin (A),
SL1 (B), and SL2 (C) transcripts. (Lane 1) 10 ~g of tRNA (control);
(lanes 2,1 I) uninjected; (lanes 3-5) SLI, SL2, and an equimolar
combination of the two, respectively; (lanes 6-8)XE12 in
combination with XmyoD (My), Xmyf5 (Mj) and mouse myogenin
(Mg), respectively; (lanes 9,10) XE12/XmyoD with SL1
and SL2, respectively; (lane 12) total RNA from neurula (stage
18) embryos. The equivalent of five explants was analyzed in
each assay. Approximate size markers were provided by an endlabeled
HinfI digest of pBR322 and are shown adjacent to undigested
probe. Full-length protected fragments are indicated. The
cardiac actin probe cross-hybridizes with ubiquitous cytoskeletal
actin transcripts that give rise to a cluster of partial protection
products (indicated in A). In B and C, the presence of the
injected, synthetic RNA gives rise to a protected band that is
larger than that obtained from the endogenous RSRF mRNA. (A
background smear was also observed routinely with injected
samples). The SL2 probe detects a second endogenous mRNA
that is coexpressed with SL2 and produces a smaller protected
fragment. Image published in: Chambers AE et al. (1994) Copyright © 1994. Image reproduced on with permission of the Publisher, Cold Spring Harbor Laboratory Press. This is an Open Access article. Larger Image Printer Friendly View |