Disruption Effect of Microplitis bicoloratus Polydnavirus EGF-like Protein, MbCRP, on Actin Cytoskeleton in Lepidopteran Insect Hemocytes  

作　　者：Kai-Jun LUO Yi PANG 

机构地区：[1]State Key Laboratory of Biocontrol and Institute of Entomology, Sun Yat-Sen University, Guangzhou 510275, China [2]Agricultural Environment and Resource Research Institute, Yunnan Academy of Agricultural Sciences, Kunming 650205, China

出　　处：《Acta Biochimica et Biophysica Sinica》2006年第8期577-585,共9页生物化学与生物物理学报（英文版）

基　　金：This work was supported by the grants from the Major State Basic Research Development Program of China （No. G2000016209）, the National Natural Science Foundation of China （No. 30530540） and 0pen-funding of the State Key Laboratory of Biocontrol at Sun YatSen University （No. 0404）

摘　　要：Microplitis bicoloratus is a braconid endoparasitic wasp associated with the polydnavirus named Microplitis bicoloratus bracovirus （MbBV）. Parasitism of Spodoptera litura larvae leads to an impaired cellular immune response and to the disappearance of the 42 kDa actin in host hemocytes. In this work, we investigated if the absence of actin in blood cells was related to MbBV infection. An MbBV gene similar to egf-like genes identified in another bracovirus was partially cloned and named Mbcrp1. The full-length gene, named Mbcrp, is transcribed throughout the course of parasitism in host hemocytes and the 30 kDa MbCRP protein was detected in hemocytes 6-7 d post-parasitization. The Mbcrp1 gene contains the cysteine-rich trypsin inhibitor-like （TIL） domain coding sequence and the expression of recombinant MbCRP1 inhibited the expression of the 42 kDa actin in Hi5 cells. The 34.1 kDa MbCRPl-green fluorescent protein fusion protein locate specifically in the cytoplasm. These results suggest that expression of MbCRP in lepidopteran insect cells is related to the disruption of the actin cytoskeleton.Microplitis bicoloratus is a braconid endoparasitic wasp associated with the polydnavirus named Microplitis bicoloratus bracovirus （MbBV）. Parasitism of Spodoptera litura larvae leads to an impaired cellular immune response and to the disappearance of the 42 kDa actin in host hemocytes. In this work, we investigated if the absence of actin in blood cells was related to MbBV infection. An MbBV gene similar to egf-like genes identified in another bracovirus was partially cloned and named Mbcrp1. The full-length gene, named Mbcrp, is transcribed throughout the course of parasitism in host hemocytes and the 30 kDa MbCRP protein was detected in hemocytes 6-7 d post-parasitization. The Mbcrp1 gene contains the cysteine-rich trypsin inhibitor-like （TIL） domain coding sequence and the expression of recombinant MbCRP1 inhibited the expression of the 42 kDa actin in Hi5 cells. The 34.1 kDa MbCRPl-green fluorescent protein fusion protein locate specifically in the cytoplasm. These results suggest that expression of MbCRP in lepidopteran insect cells is related to the disruption of the actin cytoskeleton.

关 键 词：actin cytoskeleton POLYDNAVIRUS Microplitis bicoloratus cellular immune response trypsin inhibitor-like domain MbCRP1 

分 类 号：Q969.42[生物学—昆虫学]