a sexual shift induced by silencing of a single insulin-like gene in crayfish ovarian upregulation and testicular degeneration性转变一个胰岛素样基因沉默的诱导下,小龙虾卵巢upregulation和睾丸退化.pdfVIP

A Sexual Shift Induced by Silencing of a Single Insulin- Like Gene in Crayfish: Ovarian Upregulation and Testicular Degeneration 1,2 1,2 1 1,2 1 1,2 Ohad Rosen , Rivka Manor , Simy Weil , Ohad Gafni , Assaf Linial , Eliahu D. Aflalo , Tomer Ventura1,2, Amir Sagi1,2* 1 Department of Life Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel, 2 The National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel Abstract In sequential hermaphrodites, intersexuality occurs naturally, usually as a transition state during sexual re-differentiation processes. In crustaceans, male sexual differentiation is controlled by the male-specific androgenic gland (AG). An AG- specific insulin-like gene, previously identified in the red-claw crayfish Cherax quadricarinatus (designated Cq-IAG), was found in this study to be the prominent transcript in an AG cDNA subtractive library. In C. quadricarinatus, sexual plasticity is exhibited by intersex individuals in the form of an active male reproductive system and male secondary sex characters, along with a constantly arrested ovary. This intersexuality was exploited to follow changes caused by single gene silencing, accomplished via dsRNA injection. Cq-IAG silencing induced dramatic sex-related alterations, including male feature feminization, a reduction in sperm production, extensive testicular degeneration, expression of the vitellogenin gene, and accumulation of yolk proteins in the developing oocytes. Upon silencing of the gene, AG cells hypertrophied, possibly to compensate for low hormone levels, as reflected in the poor