Transcriptome Studies Of Mouse Ovaries At Different Developmental Stages

Objective:As the reproductive organs of the female mammals,ovaries play the function of ovulation and secreting steroid.The development of ovaries and the germ cells have great complexity andsignificance.So far, many mechanisms in the developmental process are yet uncertain.In this study, we will make the transcriptome study of ovarian tissues that at the key developmental stages, through the latest edition of digital gene expression profile sequencing (RNA-Seq) and related information analysis,to find out some genes and molecules that related to the development of the ovaries and germ cells,and to provide useful clues for revealing the mechanism of ovarian development and aging.Methods:Considering the development of ovaries and the germ cells are systematic and complex, we will for the first time, comprehensively and systematically from the proliferation of the germ cells, the formation of germ cell cysts, and the cysts break down to produce primordial follicles, and the early development of primordial follicles to primary and secondary follicles, until the old mice ovaries that follicles almost depleted.Selecting the ovarian tissues involving in the key events of ovary and germ cell development, including the embryonic days12.5,2days after birth,5days after birth,10days after birth and the aged mice. First we have the experiments to verify the key developmental events at each stage of ovarian tissues,then RNA-Sequencing the ovaries(genital ridges)and make related analysis, to find out some genes and molecules that related to the development of ovary and germ celle.Results:(1)We validated the characteristics of the tissues at every developmental stage in our experiments. The results indicated that most of the germ cells are proliferating and existing in the form of germ cell cysts in the female gonad of embryo days12.5, and the2day ovaries have many adjacent and closed contacted primordial follicles,which indicated that the germ cell cysts just completed the programmed breakdown to form primordial follicles;in the day5ovaries primordial follicles are still occupies most of proportion, but there are a large number of primary follicles are in development; the day10ovaries have developmental primordia、primary and secondary follicles at the same time;and the aging mice (16months old) almostly have no follicles;(2)The whole experiment identified18915expressed genes,accounting for63.05%of the total number of genes in mouse,we got a lot of good quality sequencing differentially expressed genes;(3) we completed primary screening and enrichment of the differentially expressed genes, we have made preliminary description and analysis on the characteristics and of some germline genes and some stage expression-specific genes; (4) we found some stage expression and germline related specific genes,which can be for further deep and detailed study, to provide a lot of valuable clues for clarifing the reproductive development of female mammalsConclusion:we used the RNA-Seq to study the transcriptomics of mouse ovaries,have found a great number of genes and molecules related to the development of ovary and germ cell, It is very possible to provide some useful clues in understanding the ovarian aging by further detailed research.