Hernandez-Huertas, Luis , MORENO SANCHEZ, ISMAEL, Crespo-Cuadrado, Jesus , Vargas-Baco, Ana , Da Silva Pescador, Gabriel , Zhang, Ying , Wen, Zhihui , Florens, Laurence , Santos-Pereira, Jose M. , Bazzini, Ariel A. , Moreno-Mateos, Miguel A.
No
Embo J.
Article
Científica
1
1
8.4
01/12/2025
1,61673E+12
The maternal-to-zygotic transition (MZT) is a reprograming process encompassing zygotic genome activation (ZGA) and the clearance of maternally-provided mRNAs. While some factors regulating MZT have been identified, there are thousands of maternal RNAs whose function has not been ascribed yet. Here, we have performed a proof-of-principle CRISPR-RfxCas13d maternal screen, in which we targeted mRNAs encoding kinases and phosphatases or proteins regulating them in zebrafish. This screen identified branched-chain ketoacid dehydrogenase kinase, Bckdk, as a novel post-translational regulator of MZT. Bckdk mRNA knockdown caused epiboly defects, ZGA deregulation, H3K27ac reduction and a partial impairment of miR-430 processing. Phospho-proteomic analysis revealed that Phf10/Baf45a, a chromatin remodeling factor, is less phosphorylated upon Bckdk depletion. Further, phf10 mRNA knockdown also altered ZGA, and expression of a phospho-mimetic mutant of Phf10 rescued the developmental defects observed after bckdk mRNA depletion, as well as restored H3K27ac levels. Altogether, our results demonstrate the competence of CRISPR-RfxCas13d screenings to uncover new regulators of early vertebrate development and shed light on the post-translational control of MZT mediated by protein phosphorylation.
CRISPR-RfxCas13d; MZT; Kinases; Bckdk; Zebrafish