Wen Xi Cao, Sarah Kabelitz, Meera Gupta, Eyan Yeung, Sichun Lin, Christiane Rammelt, Christian Ihling, Filip Pekovic, Timothy C H Low, Najeeb U Siddiqui, Matthew H K Cheng, Stephane Angers, Craig A Smibert, Martin Wühr, Elmar Wahle, Howard D Lipshitz
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...
June 23, 2020: Cell Reports