Institute of Cytology and Genetics, Siberian Division of Russian Academy of Sciences, Novosibirsk 630090, Russia.
Insect Biochem Mol Biol. 2010 Dec;40(12):891-7. doi: 10.1016/j.ibmb.2010.09.001. Epub 2010 Sep 16.
Juvenile hormone (JH), which controls many developmental and physiological processes in Drosophila melanogaster, is synthesized de novo in the specialized endocrine glands, corpus allatum (CA). The present study concerns JH metabolism, reproduction and stress resistance in Drosophila with genetic ablation of a part of CA cells. The correlated regulation of JH biosynthesis and degradation in Drosophila adults has been found: ablation of CA cells led to (1) a dramatic decrease in activity of the key regulatory enzyme of JH biosynthesis, juvenile hormone acid methyl transferase and (2) a considerable increase in JH-hydrolyzing activity. It has been also shown that ablation of CA cells caused three significant physiological changes: (1) an increase in the intensity of response of JH degradation system to heat stress; (2) a disturbance of reproduction; (3) a decrease in stress resistance. Pharmacological rise of JH level rescued JH-hydrolyzing activity, fecundity and stress resistance in CA-ablated females. Pronouncedly, all the physiological effects caused by CA ablation were significant in females but not in males indicating a sexual dimorphism of JH physiological roles in Drosophila adults.
保幼激素(JH)在果蝇中控制着许多发育和生理过程,它是在专门的内分泌腺-心侧体(CA)中从头合成的。本研究关注的是果蝇中 CA 细胞部分缺失后的 JH 代谢、生殖和抗应激能力。在果蝇成虫中发现了 JH 生物合成和降解的相关调节:CA 细胞的缺失导致(1)JH 生物合成的关键调节酶-保幼激素酸甲基转移酶的活性显著下降,和(2)JH 水解活性显著增加。还表明 CA 细胞的缺失导致了三个显著的生理变化:(1)JH 降解系统对热应激的反应强度增加;(2)生殖障碍;(3)抗应激能力下降。JH 水平的药理学升高挽救了 CA 切除雌蝇中的 JH 水解活性、生育力和抗应激能力。明显的是,CA 切除引起的所有生理效应在雌性中显著,而在雄性中不显著,这表明 JH 在果蝇成虫中的生理作用存在性别二态性。