Genome-Wide Identification of Vitellogenin Gene Family and Comparative Analysis of Their Involvement in Ovarian Maturation in .

Vitellogenin () is a precursor of yolk proteins in egg-laying vertebrates and invertebrates and plays an important role in vitellogenesis and embryonic development. However, the family remains poorly characterized in , a major commercial mariculture species found along the coasts of the Yellow and Bohai Seas. In this study, 10 genes from the genomes of were identified and characterized. Phylogenetic analyses showed that the genes in crustaceans could be classified into four groups: Astacidea, Brachyra, Penaeidae, and Palaemonidae. genes were unevenly distributed on the chromosomes of , and a molecular evolutionary analysis showed that the genes were primarily constrained by purifying selection during evolution. All putative proteins were characterized by the presence of three conserved functional domains: a lipoprotein N-terminal domain (LPD_N), a domain of unknown function (DUF1943), and a von Willebrand factor type D domain (vWD). All genes exhibited higher expression in the female hepatopancreas than in other tissues, and gene expression during ovarian development suggested that the hepatopancreas is the main synthesis site in . , , and play major roles in exogenous vitellogenesis, and also plays a major role in endogenous vitellogenesis. Bilateral ablation of the eyestalk significantly upregulates mRNA expression in the female hepatopancreas, indicating that the X-organ/sinus gland complex plays an important role in ovarian development, mostly by inducing synthesis. These results could improve our understanding of the function of multiple genes in crustaceans and aid future studies on the function of genes during ovarian development in .