Expression of an Androgenic Gland-Specific Insulin-Like Peptide during the Course of Prawn Sexual and Morphotypic Differentiation

Abstract EN

The crustacean male-specific androgenic gland (AG) regulates sexual differentiation.

In the prawn Macrobrachium rosenbergii, silencing an AG-specific insulin-like encoding transcript (Mr-IAG) inhibited the development of male sexual characters, suggesting that Mr-IAG is a key androgenic hormone.

We used recombinant pro-Mr-IAG peptide to generate antibodies that recognized the peptide in AG cells and extracts, as verified by mass spectrometry.

We revealed the temporal expression pattern of Mr-IAG and studied its relevance to the timetable of sex differentiation processes in juveniles and after puberty.

Mr-IAG was expressed from as early as 20 days after metamorphosis, prior to the appearance of external male sexual characters.

Mr-IAG expression was lower in the less reproductively active orange-clawed males than in both the dominant blue-clawed males and the actively sneak mating small males.

These results suggest a role for Mr-IAG both in the timing of male sexual differentiation and in regulating reproductive strategies.