Nosema bombycis （Microsporidia） suppresses apoptosis in BmN cells （Bombyx mori）  

作　　者：Xinyi He Zhangwuke Fu Mingqian Li Han Liu Shunfeng Cai Nana Man Xingmeng Lu 

机构地区：[1]Laboratory of Invertebrate Pathology, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China [2]TongDe Hospital of Zhejiang Province, Hangzhou 310058, China [3]Hangzhou Seed Station, Hangzhou 310029, China

出　　处：《Acta Biochimica et Biophysica Sinica》2015年第9期696-702,共7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 Modern Agricultura Technology System （No. CARS-22-ZJ0202）, the National Natura Science Foundation of China （No. 31302033）, and Zheiiang Sericul rural Sci-Tech Innovation Team （No. 201 IR50028）.

摘　　要：Nosema bombycis （N. bombycis, Nb） is a fungus-related and obligate intracellular parasite that causes chronic pebrine disease in the silkworm. After infecting the host, spores obtain energy from host cells and survive for several days. This symbiosis between the pathogen and the host cell suggests that N. bombycis prevents apoptosis and reactive oxygen species （ROS） production of host cells to create the optimal environmental conditions for its growth and development. In this study, different methods were used to prove that N. bombycis suppressed apoptosis in BmN cells. Flow cytometry analysis results showed that spores suppressed apoptosis of BmN cells at 2 and 5 days after infection （P〈 0.05）. Compared with actinomycin D （ActD） treatment, apoptosis of BmN cells was apparently reduced after spore infection （P〈 0.01）. Forty-eight hours after infection, the ROS production of BmN cells was down-regulated compared with that after ActD treatment for 6 h. Furthermore, N. bombycis prevented the formation of apoptosomes by down-regulating the expression of apaf-1 and cytochrome C. In addition, N. bombycis also up-regulated the expression of buffy. Western blot analysis demonstrated that spores decreased the level of host cytochrome C at 48 and 98 h post infection. Thus, our results suggested that N. bombycis inhibited the mitochondrial apoptotic pathway of the host cells to create an optimal environment for its own survival.Nosema bombycis （N. bombycis, Nb） is a fungus-related and obligate intracellular parasite that causes chronic pebrine disease in the silkworm. After infecting the host, spores obtain energy from host cells and survive for several days. This symbiosis between the pathogen and the host cell suggests that N. bombycis prevents apoptosis and reactive oxygen species （ROS） production of host cells to create the optimal environmental conditions for its growth and development. In this study, different methods were used to prove that N. bombycis suppressed apoptosis in BmN cells. Flow cytometry analysis results showed that spores suppressed apoptosis of BmN cells at 2 and 5 days after infection （P〈 0.05）. Compared with actinomycin D （ActD） treatment, apoptosis of BmN cells was apparently reduced after spore infection （P〈 0.01）. Forty-eight hours after infection, the ROS production of BmN cells was down-regulated compared with that after ActD treatment for 6 h. Furthermore, N. bombycis prevented the formation of apoptosomes by down-regulating the expression of apaf-1 and cytochrome C. In addition, N. bombycis also up-regulated the expression of buffy. Western blot analysis demonstrated that spores decreased the level of host cytochrome C at 48 and 98 h post infection. Thus, our results suggested that N. bombycis inhibited the mitochondrial apoptotic pathway of the host cells to create an optimal environment for its own survival.

关 键 词：Nosema bombycis APOPTOSIS ROS INHIBITION cytochrome C 

分 类 号：S884.21[农业科学—特种经济动物饲养] Q255[农业科学—畜牧兽医]