Precise Temporal Regulation of Post-transcriptional Repressors Is Required for an Orderly Drosophila Maternal-to-Zygotic Transition.

TitlePrecise Temporal Regulation of Post-transcriptional Repressors Is Required for an Orderly Drosophila Maternal-to-Zygotic Transition.
Publication TypeJournal Article
Year of Publication2020
AuthorsCao, WXi, Kabelitz, S, Gupta, M, Yeung, E, Lin, S, Rammelt, C, Ihling, C, Pekovic, F, Low, TCH, Siddiqui, NU, Cheng, MHK, Angers, S, Smibert, CA, Wühr, M, Wahle, E, Lipshitz, HD
JournalCell Rep
Volume31
Issue12
Pagination107783
Date Published2020 Jun 23
ISSN2211-1247
Abstract

<p>In animal embryos, the maternal-to-zygotic transition (MZT) hands developmental control from maternal to zygotic gene products. We show that the maternal proteome represents more than half of the protein-coding capacity of Drosophila melanogaster's genome, and that 2% of this proteome is rapidly degraded during the MZT. Cleared proteins include the post-transcriptional repressors Cup, Trailer hitch (TRAL), Maternal expression at 31B (ME31B), and Smaug (SMG). Although the ubiquitin-proteasome system is necessary for clearance of these repressors, distinct E3 ligase complexes target them: the C-terminal to Lis1 Homology (CTLH) complex targets Cup, TRAL, and ME31B for degradation early in the MZT and the Skp/Cullin/F-box-containing (SCF) complex targets SMG at the end of the MZT. Deleting the C-terminal 233 amino acids of SMG abrogates F-box protein interaction and confers immunity to degradation. Persistent SMG downregulates zygotic re-expression of mRNAs whose maternal contribution is degraded by SMG. Thus, clearance of SMG permits an orderly MZT.</p>

DOI10.1016/j.celrep.2020.107783
Alternate JournalCell Rep
PubMed ID32579915
PubMed Central IDPMC7372737
Grant ListR35 GM128813 / GM / NIGMS NIH HHS / United States
T32 GM007388 / GM / NIGMS NIH HHS / United States