Jones D
J Comp Physiol B. 1985;155(5):583-90. doi: 10.1007/BF00694448.
When eggs of Trichoplusia ni (lepidoptera) are stung by a parasitic wasp, Chelonus sp., the developing host larvae precociously initiate metamorphosis ten days later. Precocious initiation of metamorphosis occurs even in 'pseudoparasitized' stung hosts which contain no living parasites at the time of symptoms of host regulation by the parasite. In feeding, penultimate instar, pseudoparasitized hosts, the corpora allata activity, hemolymph juvenile hormone esterase activity, in vivo rates of juvenile hormone metabolism and changes in hemolymph protein composition all follow the pattern of the normal last instar. This and other evidence suggests the entire developmental pattern of the last larval instar is precociously expressed in penultimate instar, pseudoparasitized hosts. The cause of precocious expression of the developmental program leading to metamorphosis is a significant decrease in the critical size parameter that, in normal larvae, signals attainment of the last instar. The induction, in preultimate instar larvae, of the entire feeding stage developmental program leading to metamorphic commitment, using either biochemical, surgical or parasitic experimental probes, has not been previously reported. The results have important implications for the study of host-parasite endocrine interaction, of normal insect metamorphosis and even of human puberty.
当粉纹夜蛾（鳞翅目）的卵被寄生蜂Chelonus sp.蜇刺后，发育中的寄主幼虫会在十天后过早地开始变态。即使在“假寄生”的被蜇刺寄主中，即在寄生虫对寄主进行调控出现症状时体内没有活寄生虫的情况下，也会发生过早的变态启动。在取食的倒数第二龄假寄生寄主中，咽侧体活性、血淋巴保幼激素酯酶活性、保幼激素在体内的代谢速率以及血淋巴蛋白质组成的变化均遵循正常末龄幼虫的模式。这一现象以及其他证据表明倒数第二龄假寄生寄主过早地表达了末龄幼虫的整个发育模式。导致变态的发育程序过早表达的原因是关键大小参数显著降低，而在正常幼虫中，该参数标志着末龄幼虫的达到。此前尚未有报道表明，使用生化、手术或寄生实验手段，在倒数第三龄幼虫中诱导出导致变态承诺的整个取食阶段发育程序。这些结果对于寄主 - 寄生虫内分泌相互作用、正常昆虫变态乃至人类青春期的研究都具有重要意义。
