论文部分内容阅读
In many lower animals,germ cell formation,migration,and maintenance depend on maternally provided determinants in germ plasm.In zebrafish,these processes have been extensively studied in terms of RNA-binding proteins and other coding genes.The role of small non-coding RNAs in the regulation of primordial germ celt (PGC) development remains largely unknown and poorly investigated,even though growing interests for the importance of miRNAs involved in a wide variety of biological processes.Here,we reported the role and mechanism of the germ plasm-specific miRNA miR-202-5p in PGC misration: (i) both maternal loss and knockdown of miR-202-5p impaired PGC misration indicated by the mislocalization and reduced number of PGCs;(ii) cdc42se1 was a direct target gene of miR-202-5p,and overexpression of Cdc42se1 in PGCs caused PGC migration defects similar to those observed in loss of miR-202-5p mutants;(iii) Cdc42se1 not only interacted with Cdc42 but also inhibited cdc42 transcription,and overexpression of Cdc42 could rescue PGC migration defects in Cdc42se1 overexpressed embryos.Thus,miR-202-5p regulates PGC migration by directly targeting and repressing Cdc42se1 to protect the expression of Cdc42,which interacts with actin to direct PGC migration.