Abstract

Ring glands or brain-ring gland complexes from third-instar Drosophila melanogaster larvae secreted ecdysone [(22R)-2beta,3beta,14alpha,22,25-pentahydroxy-5beta-cholest-7-en-6-one] and two less polar ecdysteroids (LP1 and LP2) in vitro. Radioimmunoassay with different antisera indicated that LP1 and LP2 are side-chain-modified analogues of ecdysone. In high-performance liquid chromatography, the retention time of LP2 was equivalent to that of a precursor of makisterone A [(20R,22R)-2beta,3beta,14alpha,20,22,25-hexahydroxy-24-methyl-5beta-cholest-7-en-6-one] secreted by Dysdercus fasciatus prothoracic glands in vitro. LP2 was metabolized in vitro by the fat body of Drosophila larvae to a product with the characteristics of makisterone A when analyzed by gas chromatography/mass spectrometry (selected ion monitoring). Evidence was obtained for the presence of makisterone A in Drosophila larvae. These data suggest that LP2 is 20-deoxymakisterone A (24-methylecdysone) and that makisterone A could function as an additional moulting hormone in Drosophila, although 20-deoxymakisterone A production is apparently dependent on the sterol composition of the diet. LP1 has not been identified.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.