Open AccessPgc suppresses the zygotically-acting RNA decay pathway to protect germ plasm RNAs in the Drosophila embryo
Author(s) -
Kazuko Hanyu-Nakamura,
Kazuki Matsuda,
Stephen M. Cohen,
Akira Nakamura
Publication year - 2019
Publication title -
development
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.15
H-Index - 36
eISSN - 1477-9129
pISSN - 0950-1991
DOI - 10.1242/dev.167056
Subject(s) - germ plasm , biology , germline , microbiology and biotechnology , germ cell , germ line development , genetics , piwi interacting rna , drosophila embryogenesis , cell fate determination , polarity in embryogenesis , embryonic stem cell , microrna , embryo , transcription factor , gene , rna , rna interference , embryogenesis , gastrulation
Specification of germ cells is pivotal to ensure continuation of animal species. In many animal embryos, germ cell specification depends on maternally supplied determinants in the germ plasm. Drosophila polar granule component (pgc) mRNA is a component of the germ plasm. pgc encodes a small protein that is transiently expressed in newly formed pole cells, the germline progenitors, where it globally represses mRNA transcription. pgc is also required for pole cell survival, but the mechanism linking transcriptional repression to pole cell survival remains elusive. We report that pole cells lacking pgc show premature loss of germ plasm mRNAs, including the germ cell survival factor, nanos, and undergo apoptosis. We found that pgc− pole cells misexpress multiple miRNA genes. Reduction of miRNA pathway activity in pgc− embryos partially suppressed germ plasm mRNA degradation and pole cell death, suggesting that Pgc represses zygotic miRNA transcription in pole cells to protect germ plasm mRNAs. Interestingly, germ plasm mRNAs are protected from miRNA-mediated degradation in vertebrates, albeit by a different mechanism. Thus, independently evolved mechanisms are used to silence miRNAs during germ cell specification.