Quantitative proteomic analysis revealed the protein expression characteristics of primary follicle subtypes in zebrafish

Follicles are the basic structure and functional unit of ovaries. In the previous study, we classified primary follicles (PFs) of zebrafish into four subtypes, compared the DNA methylation and RNA expression characteristics among different subtypes follicles, and preliminarily analyzed the molecular mechanism of PFs development. However, the protein expression characteristics of the four subtypes of PFs remain poorly understood. In this study, a total of 9635 proteins were identified in the four subtypes PFs of zebrafish by proteomic analysis. The proteins highly expressed in the PF-ii and PF-iii were enriched in Notch, MAPK, and mTOR signaling pathways. By combined transcriptomic and proteomic analysis screened five key candidate molecules involved in PFs developmental regulation. These results provide reference to the molecular mechanisms underlying follicular development in fish. • The protein profiles of four subtypes of primary follicles (PFs) in zebrafish have been characterized in detail for the first time. • Functional enrichment analysis of PFs proteins at different stages was carried out. • Screened five key candidate molecules involved in PFs developmental regulation.