Hypothalamus-pituitary-gonad axis transcriptome profiling for sex differentiation in Acipenser sinensis

Abstract

Chinese sturgeon (Acipenser sinensis), a critically endangered Acipenseridae family member, is one of the largest anadromous, native fish in China. Numerous research programmes and protection agencies have focused on breeding and preserving this endangered species. However, available information is limited on the different stages of sex development, especially on the reproductive regulation of the hypothalamus-pituitary-gonad (HPG) axis of A. sinensis. To unravel the mechanism of gene interactions during sex differentiation and gonad development of A. sinensis, we performed transcriptome sequencing using HPG samples from male and female A. sinensis in two developmental stages. In this study, 271.19 Gb high-quality transcriptome data were obtained from 45 samples belonging to 15 individuals (six in stage I, six males and three females in stage II). These transcriptomic data will help us understand the reproductive regulation of the HPG axis in the development stages of A. sinensis and provide important reference data for genomic and genetic studies in A. sinensis and related species.

Fig. 1

Characteristics of Acipenser sinensis unigenes with a BLASTx search against databases. (a) Species distribution of the best BLASTx matches for each unigene. (b) The annotation of the Acipenser sinensis unigenes in the NR, InterPro, Swiss-Prot, COG and KEGG databases.

Fig. 2

Gene Ontology classification of the Acipenser sinensis transcriptome. A total of 49,015 unigenes with BLASTx matched against the animal NR database were classified into three main GO categories (biological process, cellular component, molecular function) and 58 sub-categories. The left-hand scale on the y-axis shows the detailed names of the sub-categories. The x-axis indicates the number of unigenes in the same category.

Fig. 3

Principle component analysis (PCA) and different gene expression analysis in the Acipenser sinensis transcriptome. (a) PCA plot of 45 samples based on estimated expression values. (b) The statistics of different expression genes in different pairwise comparisons. A total of 18 pairwise comparisons among the HPG of different sexes were performed. (F: Female; M: Male; U: unknown; H: hypothalamus; P: pituitary; G: gonad).

Fig. 4

SSR distribution of Acipenser sinensis unigenes.