. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. METAMORPHOSIS AND GENE EXPRESSION 121 100 35 80 o .c a fe 60 | 40 ^ 20 Cs+emetine Cs emetine BIO FSW Treatment Figure 8. Effects of the translation inhibitor emetine on induction ot metamorphosis in Hydnrides elegans. Larvae were incubated for 3 h in 1 \M emetine in filtered seawater (FSWl that also contuinted 10 mM CsCl to induce metamorphosis. Solutions were replaced with FSW after 3 h. and the larvae were allowed to complete metamorphosis for another 16 h. Bars indicate percentages of larvae that metamorphosed ± I SE (;i
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. METAMORPHOSIS AND GENE EXPRESSION 121 100 35 80 o .c a fe 60 | 40 ^ 20 Cs+emetine Cs emetine BIO FSW Treatment Figure 8. Effects of the translation inhibitor emetine on induction ot metamorphosis in Hydnrides elegans. Larvae were incubated for 3 h in 1 \M emetine in filtered seawater (FSWl that also contuinted 10 mM CsCl to induce metamorphosis. Solutions were replaced with FSW after 3 h. and the larvae were allowed to complete metamorphosis for another 16 h. Bars indicate percentages of larvae that metamorphosed ± I SE (;i = 4 repli- cates/treatment). Cs, 10 mM CsCl/3 h: emetine. 1 /xM emetine; BIO, substratum coated with a marine biofilm; FSW, seawater filtered through a filter. of DRB, transcription and translation were drastically re- duced without inhibiting induction of metamorphosis in competent larvae of P. sibogae. Further experiments showed that activation of the receptor for the metamorphie signal is not affected by reduction in transcription, but new transcription appears to be necessary for the final, elonga- tion phase of metamorphosis in P. sibogae (Del Carmen and Hadfield. 2000). The observation that metamorphosis in H. elegans progresses in the presence of DRB, together with the dem- onstration that DRB effectively inhibits RNA synthesis, indicates that the initiation and early phases of metamor- phosis in this species are independent of new RNA synthe- sis. However, the fact that we were never able to completely inhibit RNA synthesis leaves open the possibility that syn- thesis of some mRNAs was resistant to the action of DRB, and thus that new transcripts may play an essential role during metamorphosis for the first hours after induction. Transcriptional resistance to DRB in HeLa cells was re- ported by Zandomeni el al. (1982). The observation that development in the presence of DRB stops at the point when branchial radicle development begins indicates that new trans
Size: 1892px × 1320px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
