Arakane Y, Muthukrishnan S, Kramer K J, Specht C A, Tomoyasu Y, Lorenzen M D, Kanost M, Beeman R W
USDA-ARS-Grain Marketing and Production Research Center, Manhattan, KS 66502, USA.
Insect Mol Biol. 2005 Oct;14(5):453-63. doi: 10.1111/j.1365-2583.2005.00576.x.
Functional analysis of the two chitin synthase genes, TcCHS1 and TcCHS2, in the red flour beetle, Tribolium castaneum, revealed unique and complementary roles for each gene. TcCHS1-specific RNA interference (RNAi) disrupted all three types of moult (larval-larval, larval-pupal and pupal-adult) and greatly reduced whole-body chitin content. Exon-specific RNAi showed that splice variant 8a of TcCHS1 was required for both the larval-pupal and pupal-adult moults, whereas splice variant 8b was required only for the latter. TcCHS2-specific RNAi had no effect on metamorphosis or on total body chitin content. However, RNAi-mediated down-regulation of TcCHS2, but not TcCHS1, led to cessation of feeding, a dramatic shrinkage in larval size and reduced chitin content in the midgut.
对赤拟谷盗（Tribolium castaneum）中两个几丁质合酶基因TcCHS1和TcCHS2的功能分析揭示了每个基因独特且互补的作用。针对TcCHS1的RNA干扰（RNAi）破坏了所有三种蜕皮类型（幼虫-幼虫、幼虫-蛹和蛹-成虫），并大大降低了全身几丁质含量。外显子特异性RNAi表明，TcCHS1的剪接变体8a是幼虫-蛹和蛹-成虫蜕皮所必需的，而剪接变体8b仅为后者所必需。针对TcCHS2的RNAi对变态或全身几丁质含量没有影响。然而，RNAi介导的TcCHS2而非TcCHS1的下调导致取食停止、幼虫大小显著缩小以及中肠几丁质含量降低。
