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In the first days of adulthood, ovary size and sexual receptivity increase in female sand crickets ( Gryllus firmus Scudder, 1902). We tested whether these are mechanistically linked by juvenile hormone (JH), which has been implicated in gonadal development and sexual behavior in other insects. Treatment of young females with the JH analog, methoprene, accelerates oocyte maturation and triggers flight-muscle histolysis, but does not affect sexual receptivity. These results are consistent with earlier studies which suggest that physiological and behavioral components of sexual maturation in crickets are separately regulated. [ABSTRACT FROM AUTHOR]

Three different peptide families have been named 'allatostatins' (ASTs), based on their initial purifications which were based on their ability to inhibit juvenile hormone (JH) biosynthesis. These include ( i) a family of peptides that have a consensus C-terminal sequence Y/FXFGL-NH2; ( ii) a family of peptides with a conserved C-terminal sequence W(X)6W-NH2; and( iii) a family of peptides with C-terminal sequence PISCF, some of which are C-terminally-amidated. Each allatostatin family has functions distinct and apart from the inhibition of JH biosynthesis. A peptide family known as the 'allatotropins' serve to stimulate JH biosynthesis. This family of peptides also has been proven to exert multiple effects dependent on the species in question. Genome and peptidome projects are uncovering new members of these families and it is clear that these structures are not just confined to Insecta but are found in a range of invertebrates. The receptors for these neuropeptides have been identified and tested experimentally for specific ligand binding. The Y/FXFGLa-ASTs exert their action through galanin-like receptors, W(X)6Wa-ASTs through a sex peptide-binding receptor, and PISCF-ASTs through somatostatin-like receptors. These receptors are conserved through evolutionary time and are being identified in numerous invertebrates by way of genome projects. [ABSTRACT FROM AUTHOR]