Schwartz Aaron Z A, Abdu Yusuff, Nance Jeremy
Department of Cell Biology, NYU Grossman School of Medicine, New York NY 10016.
Skirball Institute of Biomolecular Medicine, NYU Grossman School of Medicine, New York NY 10016.
bioRxiv. 2023 Jul 10:2023.07.10.548405. doi: 10.1101/2023.07.10.548405.
Rapid and conditional protein depletion is the gold standard genetic tool for deciphering the molecular basis of developmental processes. Previously, we showed that by conditionally expressing the E3 ligase substrate adaptor ZIF-1 in somatic cells, proteins tagged with the first CCCH Zn finger (ZF1) domain from the germline regulator PIE-1 degrade rapidly, resulting in loss-of-function phenotypes. The described role of ZIF-1 is to clear PIE-1 and several other CCCH Zn finger proteins from early somatic cells, helping to enrich them in germline precursor cells. Here, we show that proteins tagged with the PIE-1 ZF1 domain are subsequently cleared from primordial germ cells in embryos and from undifferentiated germ cells in larvae and adults by ZIF-1. We harness germline ZIF-1 activity to degrade a ZF1-tagged heterologous protein from PGCs and show that its depletion produces phenotypes equivalent to those of a null mutation. Our findings reveal that ZIF-1 switches roles from degrading CCCH Zn finger proteins in somatic cells to clearing them from undifferentiated germ cells, and that ZIF-1 activity can be harnessed as a new genetic tool to study the early germ line.
快速且有条件的蛋白质耗竭是用于解读发育过程分子基础的金标准遗传工具。此前，我们表明通过在体细胞中条件性表达E3连接酶底物衔接子ZIF-1，来自生殖系调节因子PIE-1的首个CCCH锌指（ZF1）结构域标记的蛋白质会迅速降解，从而导致功能丧失表型。ZIF-1的上述作用是从早期体细胞中清除PIE-1和其他几种CCCH锌指蛋白，有助于在生殖系前体细胞中富集它们。在此，我们表明带有PIE-1 ZF1结构域标记的蛋白质随后会被ZIF-1从胚胎中的原始生殖细胞以及幼虫和成虫的未分化生殖细胞中清除。我们利用生殖系ZIF-1活性从原始生殖细胞中降解一种ZF1标记的异源蛋白，并表明其耗竭产生的表型与无效突变的表型相当。我们的研究结果表明，ZIF-1的作用从在体细胞中降解CCCH锌指蛋白转变为从未分化生殖细胞中清除它们，并且ZIF-1活性可作为一种新的遗传工具用于研究早期生殖系。
