Department of Biology, Duke University, Durham, North Carolina 27708; email:
Annu Rev Entomol. 2015 Jan 7;60:141-56. doi: 10.1146/annurev-ento-010814-020841. Epub 2014 Oct 8.
The developmental mechanisms that control body size and the relative sizes of body parts are today best understood in insects. Size is controlled by the mechanisms that cause growth to stop when a size characteristic of the species has been achieved. This requires the mechanisms to assess size and respond by stopping the process that controls growth. Growth is controlled by two hormones, insulin and ecdysone, that act synergistically by controlling cell growth and cell division. Ecdysone has two distinct functions: At low concentration it controls growth, and at high levels it causes molting and tissue differentiation. Growth is stopped by the pulse of ecdysone that initiates the metamorphic molt. Body size is sensed by either stretch receptors or oxygen restriction, depending on the species, which stimulate the high level of ecdysone secretion that induces a molt. Wing growth occurs mostly after the body has stopped growing. Wing size is adjusted to body size by variation in both the duration and level of ecdysone secretion.
控制体型和身体各部分相对大小的发育机制在昆虫中得到了最好的理解。体型是由导致生长停止的机制控制的，当达到物种特有的体型特征时，生长就会停止。这需要机制来评估大小，并通过停止控制生长的过程来做出反应。生长由两种激素胰岛素和蜕皮激素控制，它们通过控制细胞生长和细胞分裂协同作用。蜕皮激素有两个明显的功能：在低浓度时它控制生长，在高浓度时它引起蜕皮和组织分化。生长是由启动变态蜕皮的蜕皮激素脉冲停止的。体型是通过伸展感受器或氧气限制来感知的，这取决于物种，它们会刺激高水平的蜕皮激素分泌，从而引发蜕皮。翅膀的生长主要发生在身体停止生长之后。翅膀的大小通过蜕皮激素分泌的持续时间和水平的变化来适应身体的大小。
