Differential expression of the two duplicated insecticyanin genes, ins-a and ins-b, in the black mutant of Manduca sexta.
Differential expression of the two duplicated insecticyanin genes, ins-a and ins-b, in the black mutant of Manduca sexta.
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两个重复的虫青素基因 ins-a 和 ins-b 在天蛾黑色突变体中的差异表达。
DOI：
10.1006/abbi.1996.0226
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发表时间：
1996
影响因子：
3.9
通讯作者：
Li,WC
中科院分区：
文献类型：
--
作者：
Li,WC
黑（bl）突变型天蛾幼虫在蜕皮至5龄期间不产生保幼激素（JH）。为了研究JH对ins-aandins-B基因表达的调控，我们研究了这两种基因在发育过程中的变化。在刚蜕皮的幼虫表皮中，这两种mRNA几乎检测不到。蜕皮后12小时，这两种mRNA出现在低水平，然后逐渐增加，从第1天到第2天早上上升到一个平台，并在第2天的ins-bmRNA。在这些早期发育阶段，突变体中两种mRNA的表皮水平远低于野生型幼虫中观察到的水平。在5龄第3天，当幼虫表皮开始化蛹时，突变体和野生型幼虫中的这两种mRNA表现出相似的差异表达模式。在脂肪体中，bothins-aandins-bmRNAs的水平高于野生型幼虫中发现的水平。外源JH使突变体0日龄5龄幼虫的表皮和脂肪体中这两种mRNA的水平几乎恢复到相同时期野生型动物的水平。这些结果表明，JH可能会增加这两个昆虫花青素基因在表皮中的表达，但部分抑制其在脂肪体中的表达在早期发育的野生型5龄幼虫。
Theblack(bl) mutant larvae ofManduca sextaproduces no detectable juvenile hormone (JH) during the molt to the 5th instar. To investigate the JH control of expression of the two insecticyanin genes,ins-aandins-b,developmental changes of the two mRNAs were examined in this mutant. In the epidermis of the freshly ecdysed larvae, the two mRNAs were hardly detectable. Twelve hours after ecdysis, the two mRNAs appeared in low levels and were then gradually increased withins-amRNA rising to a plateau from Day 1 to Day 2 morning andins-bmRNA in Day 2. During these early developmental stages, the epidermal level of the two mRNAs in theblmutant was substantially lower than that observed in the wild-type larvae. On Day 3 of the 5th instar when the larval epidermis becomes pupally committed, the two mRNAs in bothblmutant and wild-type larvae show a similar differential expression pattern. In the fat body, the level of bothins-aandins-bmRNAs was higher than that found in the wild-type larvae. Exogenous JH almost restores the level of the two mRNAs in both epidermis and fat body of the Day 0 5th-instarblmutant larvae to that observed in wild-type animals of the same stage. These results suggest that JH may enhance expression of the two insecticyanin genes in the epidermis but partially repress their expression in the fat body during early development of the wild-type 5th-instar larvae.