AUTHOR=Guo Qing , Li Shihao , Lv Xinjia , Xiang Jianhai , Manor Rivka , Sagi Amir , Li Fuhua 

TITLE=Sex-Biased CHHs and Their Putative Receptor Regulate the Expression of IAG Gene in the Shrimp Litopenaeus vannamei

JOURNAL=Frontiers in Physiology

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2019.01525

DOI=10.3389/fphys.2019.01525

ISSN=1664-042X

ABSTRACT=<p>The “eyestalk-androgenic gland (AG)-testis” endocrine axis is involved in male sexual differentiation of crustaceans. The insulin-like androgenic gland hormone (IAG), secreted from the AG, plays a central role in this axis, however key factors upstream the IAG are still poorly understood. Here, two crustacean hyperglycemic hormone (CHH) genes (<italic>LvCHH1</italic> and <italic>LvCHH2</italic>) and their putative receptor guanylate cyclase (<italic>LvGC</italic>) were identified in <italic>Litopenaeus vannamei</italic>. LvCHH1 and LvCHH2 belonged to CHH subfamily I members and LvGC was a membrane-bound guanylate cyclase. They were all differentially expressed in eyestalks and gonads of males and females. RNA interference (RNAi) of either <italic>LvCHH1</italic> or <italic>LvCHH2</italic> increased <italic>LvIAG</italic> expression, while injection of their recombinant protein decreased <italic>LvIAG</italic> expression, indicating that LvCHH1 and LvCHH2 are inhibitory factors of <italic>LvIAG</italic> expression. Yeast two-hybrid assay showed that both LvCHH1 and LvCHH2 interacted with LvGC and their RNAi and recombinant protein injection exerted opposite regulatory effects on the transcriptional expression of <italic>LvGC</italic>. Meanwhile, knockdown of <italic>LvGC</italic> increased <italic>LvIAG</italic> expression. These results suggest that LvGC is the receptor of LvCHH1 and LvCHH2 and they are all involved in male sexual development by regulating <italic>LvIAG</italic> expression. The present study unveils missing upstream elements in the “eyestalk-AG-testis” endocrine axis in crustacean.</p>