@article{03b87ee1bf774dbe9b3235eb888088ac,
title = "Precise Temporal Regulation of Post-transcriptional Repressors Is Required for an Orderly Drosophila Maternal-to-Zygotic Transition",
abstract = "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.",
keywords = "Cup, ME31B, RNA-binding, Smaug, Trailer hitch, embryogenesis, proteome, ubiquitin ligase",
author = "Cao, {Wen Xi} and Sarah Kabelitz and Meera Gupta and Eyan Yeung and Sichun Lin and Christiane Rammelt and Christian Ihling and Filip Pekovic and Low, {Timothy C.H.} and Siddiqui, {Najeeb U.} and Cheng, {Matthew H.K.} and Stephane Angers and Smibert, {Craig A.} and Martin W{\"u}hr and Elmar Wahle and Lipshitz, {Howard D.}",
note = "Funding Information: We thank Olivia Rissland for communicating unpublished results prior to submission of a related manuscript; Angelo Karaiskakis and Hua Luo for technical assistance at the University of Toronto; Andrea Sinz for supporting the MS measurements at the University of Halle; Paul Schedl, Eric Wieschaus, and Trudi Sch{\"u}pbach for helpful advice and suggestions, and Lillia Ryazanova for technical assistance at Princeton University; Michael G{\"o}tze, Luz Irina Calderon Villalobos, and Michael Niemeyer for helpful discussions in Halle; and Thomas Hurd for a critical review of the manuscript in Toronto. Antibodies were kindly provided by Akira Nakamura (rabbit anti-Cup, TRAL, ME31B) and Gregory Rogers (guinea pig anti-SLMB). W.X.C. was supported in part by an Ontario Graduate Scholarship and University of Toronto Open Scholarships. This research was supported by the following funding agencies: Canadian Institutes of Health Research (grant PJT-159702 to H.D.L.), Natural Sciences and Engineering Research Council of Canada (H.D.L. and C.A.S.), Deutsche Forschungsgemeinschaft (grant WA 548/17-1 within SPP 1935 to E.W.), and National Institutes of Health (grants R35GM128813 to M.W. and T32GM007388 to E.Y.). The project was designed by H.D.L. and E.W. The unfertilized egg time course, RNAi experiments, analyses of FLAG-SMG and FLAG-SMG767Δ999 time course westerns, and qRT-PCR experiments to assess mRNAs in FLAG-SMG and FLAG-SMG767Δ999 were carried out by W.X.C. under the supervision of H.D.L.; the RBP western time course, MG132 experiments, and GFP-Muskelin/CG3295 westerns were carried out by S.K. under the supervision of E.W.; TMTc+ MS was carried out by M.G. and E.Y. under the supervision of M.W.; FLAG-SMG IP-MS was carried out by W.X.C. and S.L. under the supervision of H.D.L. and S.A. respectively; GFP-Muskelin and GFP-SLMB IP-MS were carried out by S.K. C.R. and C.I. under the supervision of E.W.; F.P. generated the anti-eIF4E and anti-CG3295 antibodies under the supervision of E.W.; T.C.H.L. wrote the script to calculate SRE scores under the supervision of H.D.L.; N.U.S. constructed the transgenes to express FLAG-SMG and FLAG-SMG767Δ999 under the supervision of H.D.L.; and M.H.K.C. showed that FLAG-SMG767Δ999 persists under the supervision of C.A.S. W.X.C. wrote the first draft of the manuscript, which was revised by H.D.L. with major input from E.W. and M.W. as well as input from the other co-authors. The authors declare no competing interests. Funding Information: We thank Olivia Rissland for communicating unpublished results prior to submission of a related manuscript; Angelo Karaiskakis and Hua Luo for technical assistance at the University of Toronto; Andrea Sinz for supporting the MS measurements at the University of Halle; Paul Schedl, Eric Wieschaus, and Trudi Sch{\"u}pbach for helpful advice and suggestions, and Lillia Ryazanova for technical assistance at Princeton University; Michael G{\"o}tze, Luz Irina Calderon Villalobos, and Michael Niemeyer for helpful discussions in Halle; and Thomas Hurd for a critical review of the manuscript in Toronto. Antibodies were kindly provided by Akira Nakamura (rabbit anti-Cup, TRAL, ME31B) and Gregory Rogers (guinea pig anti-SLMB). W.X.C. was supported in part by an Ontario Graduate Scholarship and University of Toronto Open Scholarships. This research was supported by the following funding agencies: Canadian Institutes of Health Research (grant PJT-159702 to H.D.L.), Natural Sciences and Engineering Research Council of Canada (H.D.L. and C.A.S.), Deutsche Forschungsgemeinschaft (grant WA 548/17-1 within SPP 1935 to E.W.), and National Institutes of Health (grants R35GM128813 to M.W. and T32GM007388 to E.Y.). Publisher Copyright: {\textcopyright} 2020 The Author(s)",
year = "2020",
month = jun,
day = "23",
doi = "10.1016/j.celrep.2020.107783",
language = "English (US)",
volume = "31",
journal = "Cell Reports",
issn = "2211-1247",
publisher = "Cell Press",
number = "12",
}