De novo Transcriptome Analysis of Portunus trituberculatus Ovary and Testis by RNA-Seq: Identification of Genes Involved in Gonadal Development

Abstract

The swimming crab Portunus trituberculatus is a commercially important crab species in East Asia countries. Gonadal development is a physiological process of great significance to the reproduction as well as commercial seed production for P. trituberculatus. However, little is currently known about the molecular mechanisms governing the developmental processes of gonads in this species. To open avenues of molecular research on P. trituberculatus gonadal development, Illumina paired-end sequencing technology was employed to develop deep-coverage transcriptome sequencing data for its gonads. Illumina sequencing generated 58,429,148 and 70,474,978 high-quality reads from the ovary and testis cDNA library, respectively. All these reads were assembled into 54,960 unigenes with an average sequence length of 879 bp, of which 12,340 unigenes (22.45% of the total) matched sequences in GenBank non-redundant database. Based on our transcriptome analysis as well as published literature, a number of candidate genes potentially involved in the regulation of gonadal development of P. trituberculatus were identified, such as FAOMeT, mPRγ, PGMRC1, PGDS, PGER4, 3β-HSD and 17β-HSDs. Differential expression analysis generated 5,919 differentially expressed genes between ovary and testis, among which many genes related to gametogenesis and several genes previously reported to be critical in differentiation and development of gonads were found, including Foxl2, Wnt4, Fst, Fem-1 and Sox9. Furthermore, 28,534 SSRs and 111,646 high-quality SNPs were identified in this transcriptome dataset. This work represents the first transcriptome analysis of P. trituberculatus gonads using the next generation sequencing technology and provides a valuable dataset for understanding molecular mechanisms controlling development of gonads and facilitating future investigation of reproductive biology in this species. The molecular markers obtained in this study will provide a fundamental basis for population genetics and functional genomics in P. trituberculatus and other closely related species.

Functional insights into the testis transcriptome of the edible sea urchin Loxechinus albus

“…Within these pathways, some kinase receptors (e.g., RTK) bind a variety of growth factors (e.g., TGF-β: KO04350; VEGFR: KO04370), mediating cell-cell interactions during sea urchin development51. Other signalling pathways that are known to be involved in a variety of biological processes, including development, are the wnt (KO04310), the Hedgehog (KO04340), the Jak-STAT (KO04630), the Notch (KO04330), the Hippo (KO04391), the FoxO (KO04068), the Ca 2+ (KO04020) the cAMP (KO04024), the cGMP (KO04022), the PI3K-Akt (KO04151) and the Phosphatidylinositol (KO04070) pathway124852535455. Components of these signaling pathways have been highly evolutionarily conserved among metazoans56, and are active in the testis transcriptome of L. albus .…”

Testis‐specific RNA‐Seq of Calligrapha (Chrysomelidae) as a transcriptomic resource for male‐biased gene inquiry in Coleoptera

“…; Meng et al . ). In our case, annotation success reached 32.8–44.6%, but these figures may be comparatively inflated, since we restricted annotation to contigs longer than 499 nt, with higher annotation rates compared to shorter fragments (Riesgo et al .…”

“…; Meng et al . ). Yet, the global comparison of testis transcriptomes, unless targeting close relatives or physiological alternatives in the same species, may be pointless, given that each transcriptome reflects not only taxonomic, but also individual physiological idiosyncrasy (Scolari et al .…”

Differential expression of Toll-like receptors in goat dominant and nondominant follicles

“…Previous studies have demonstrated that the WNT4 gene was expressed in the ovary and is involved in gonadal development (Meng et al, 2015). It is an irreplaceable signal gene for the development of the ovary; the expression of a WNT4 knock-out gene in gonads led to the sexually dimorphic functions (Naillat et al, 2015).…”