RNAi Reveals Role of Insulin-Like Androgenic Gland Hormone 2 (IAG2) in Sexual Differentiation and Growth in Hermaphrodite Shrimp

Insulin-like androgenic gland hormone (IAG) is the most widely known that regulates sexual differentiation in crustaceans. Previously, a transcriptome study described two transcripts of IAGs ( Lvit-IAG1 and Lvit-IAG2 ) peppermint shrimp Lysmata vittata , species characterized by rare reproductive system protandric simultaneous hermaphroditism (PSH). Herein, we explored function Lvit -IAG2 via RNA interference (RNAi) experiments, then compared functional differences between IAGs. We demonstrated positively regulated expression crustacean hyperglycemic Lvit-CHH eyestalk ganglion but exhibited no significant effect on gonad-inhibiting Lvit-GIHs female sex Lvit-CFSHs ). Besides, gene knockdown caused degeneration appendices masculinae (AM) suppressed germ cells at secondary spermatocyte stage. Moreover, silencing impeded ovarian development, including smaller previtellogenic oocytes, lower vitellogenin Lvit-Vg hepatopancreas receptor Lvit-VgR region. Notably, individual growth species. Collectively, findings from this demonstrate -IAG1 coordinatively to modulate L. ; meanwhile, stimulates PSH