Hormonal control of pupal commitment and programmed cell death

目前的研究确定并表明，在propqsed期间。(1)激素滴度：血淋巴保幼激素和蜕皮激素滴度测定期间，每12小时，从第三体育场到化蛹和每2小时蜕皮激素从第四体育场通过化蛹。(2)蛹的翅盘定型：翅盘定型的变化在最后一次幼虫蜕皮后16 h完成。20-羟基蜕皮素并没有加速这种变化的速率，而JH在生理剂量下也未能抑制这种变化。JH也没有影响承诺的变化。20 E.承诺的改变可以在头囊滑动（HCS）时开始。HCS后，椎间盘对20 E的反应性显著增加，而对JH的反应性则下降。第4龄早期的盘，在20 E体外不能化蛹，能够通过两步孵育，首先不使用激素，然后用20 E攻击来化蛹。在这种条件下，光盘蛹承诺和承诺强烈抑制JH浓度低于生理。(3)前丝腺细胞程序性死亡：20 E在体外诱导前丝腺细胞凋亡。20E攻击后，死亡所需的基因表达和蛋白质合成分别在8和18 h内完成。然而，20E必须存在42小时才能完成死亡。沿着其他证据表明，20 E在18 h后通过膜结合受体起作用，第二信使是环AMP。目前已克隆了7个早期基因，其中5个与其它动物已知基因具有同源性，2个不具有开放阅读框架。目前正在对其职能进行分析。

Present research determined and showed the followings during the propqsed period.(1) Hormone titer : Hemolymph juvenile hormone and ecdysteroid titers were determined every 12 h for JH during a period from third stadium to pupation and every 2 h for ecdysteroids from 4th stadium through pupation.(2) Pupal commitment of for wing discs : The change in commitment in wing discs was found to be finished for 16 h after last larval ecdysis. 20-Hydroxyecdyosne did not accelerate the rate of the change and JH failed to suppress the change at a physiological dose. JH also did not affect the change in commitment by. 20E. The change in commitment may be initiated at the time of head capsule slippage (HCS). After HCS, the discs became responsive dramatically to 20E while lost their responsiveness to JH. The discs of early 4th stadium, that were not pupally committed by 20E in vitro, were able to be pupally committed by two step incubation, first with no hormone followed by 20E challenge. In such conditions, the discs were pupally committed and the commitment was strongly suppressed by JH at a concentration lower than physiological one.(3) Programmed cell death of anterior silk gland : Apoptosis of anterior silk gland is induced by 20E in vitro. After 20E challenge, gene expression and protein synthesis necessary for the death were completed within 8 and 18 h, respectively. Nevertheless, 20E must be present for 42 h for completion of the death. Along with other evidence, 20E was suggested to act after 18 h through a membrane-bound receptor and the second messenger is cyclic AMP. Seven early genes have been cloned and five of them exhibited homology of known genes in other animals but two did not possess open reading frame. Analysis of their function is under progress.