斜纹夜蛾几丁质酶家族基因鉴定与时空表达分析

昆虫GH18家族几丁质酶属于多基因家族,在昆虫的蜕皮与变态过程中发挥着至关重要的作用,它催化表皮几丁质的降解.斜纹夜蛾是一种重要的农业害虫,危害290多种植物,但对其几丁质酶未深入研究.该文通过斜纹夜蛾转录组学分析,发现了12种潜在的几丁质酶,分属于8类.对这些几丁质酶在斜纹夜蛾变态发育时在表皮、中肠以及脂肪体的时空表达分析结果表明,Sl Cht5,Sl Cht9和Sl Cht2的表达水平在幼虫转化为蛹时上调表达,说明这些几丁质酶可能参与了斜纹夜蛾变态时期的脱皮作用;而其他几丁质酶的表达具有组织特性,表明它们可能具有不同功能,如Sl Cht6仅在中肠和脂肪体中表达,Sl Cht11,Sl Cht12和Sl Cht16主要在中肠和表皮表达,Sl IDGF2仅在表皮有表达,Sl IDGF3和Sl Cht9在三大组织均有表达.本研究结果对斜纹夜蛾几丁质酶家族基因的鉴定和时空表达作了初步的分析,为研究它们在斜纹夜蛾发育中的功能与调控打下基础.

Identification and Expression Analysis of Chitinases in Common Cutworm,Spodoptera Litura

Insect chitinase, which belongs to the family 18 glycosylhydrolases, plays an key role during insect molting and metamorphosis. Spodoptera litura damages more than 290 plants, but chitinases in this species have not been clearly studied. In this study, 12 putative chitinase-like proteins were identified in S. litura and classified into eight different groups. The expression patterns of these chitinase genes in the three tissues including midgut, fat body and epidermis during the metamorphosis were analyzed. The results showed that the expression levels of SlCht5, SlCht9 and SlCht2 increased during metamorphosis. SlCht6 expressed in the midgut and fat body; SlCht11, SlCht12 and SlCht16 expressed in the midgut and epidermis; SlIDGF2 expressed only in epidermis; while SlIDGF3 and SlCht9 expressed in the three tissues. The results suggest that different chitinases might play different roles during development in S. litura, SlCht5, SlCht9 and SlCht2 might be associated with metamorphosis. The results derived from this study set up a basis for further investigation of function and regulation of these genes in this insect.