Developmental changes in structure and polypeptide profile of the androgenic gland of the freshwater prawn Macrobrachium rosenbergii

Although the mechanism of sex-differentiation in crustaceans has yet to be defined, the androgenic gland (AG) is thought to be the exclusive organ tha t produces the androgenic hormone (AH) which induces male sexual developmen t. This paper presents results of light and transmission electron microscop y and total protein analysis of androgenic glands from three male morphotyp es (orange-claw, orange-blue-claw and blue-claw) of the freshwater prawn, M acrobrachium rosenbergii. Highest protein content (76 mug/AG) was found in the blue-claw morphotype as compared to the orange-blue-claw (45 mug/AG) an d the orange-claw morphotype (19 mug/AG). Sodium dodecyl sulfate polyacryla mide gel electrophoresis (SDS-page) analysis of the cell free extract of th e AG from the three morphotypes revealed four polypeptides (similar to 16, similar to 18, similar to 23 and similar to 26 Kd) which quantitatively inc rease from the sexually immature orange-claw to the sexually mature blue-cl aw morphotype. The 16 and 18 Kd polypeptides could be the AHs.