Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China.
Arch Insect Biochem Physiol. 2011 Mar;76(3):130-43. doi: 10.1002/arch.20353. Epub 2010 May 13.
Serine proteases play important roles in food digestion and immune response during insect development. A full-length cDNA (Slctlp1) encoding a chymotrypsin-like serine protease was cloned from Spodoptera litura and characterized for its cDNA structure, developmental and induced expression and localization. The deduced protein of the Slctlp1 cDNA contains a catalytic triad and a substrate specificity pocket found in most of the serine proteases. Both the transcripts and protein of Slctlp1 were predominately expressed in the midgut at the feeding stages during the larval development. Immunohistochemistry analysis indicated that the SLCTLP1 protein was predominately present in the midgut of the 6th instar feeding larvae. Starvation suppressed the expression of Slctlp1 gene and protein in 6th instar larvae and the protein expression was increased again by re-feeding the insect. The results suggest that the cloned Slctlp1 cDNA may be involved in food protein digestion at the feeding stages during larval development.
丝氨酸蛋白酶在昆虫发育过程中的食物消化和免疫反应中发挥着重要作用。本研究从斜纹夜蛾中克隆了一个编码胰凝乳蛋白酶样丝氨酸蛋白酶的全长 cDNA（Slctlp1），并对其 cDNA 结构、发育和诱导表达及定位进行了研究。Slctlp1 cDNA 编码的蛋白含有一个催化三联体和一个在大多数丝氨酸蛋白酶中发现的底物特异性口袋。在幼虫发育的取食阶段，Slctlp1 的转录本和蛋白主要在中肠中表达。免疫组织化学分析表明，SLCTLP1 蛋白主要存在于 6 龄取食幼虫的中肠中。饥饿抑制了 6 龄幼虫中 Slctlp1 基因和蛋白的表达，重新喂食昆虫后蛋白表达再次增加。这些结果表明，克隆的 Slctlp1 cDNA 可能参与幼虫发育过程中取食阶段的食物蛋白消化。
