title: A transcriptome analysis suggests apoptosis-related signaling pathways in hemocytes of Spodoptera litura after parasitization by Microplitis bicoloratus.
abstract: Microplitis bicoloratus parasitism induction of apoptotic DNA fragmentation of host Spodoptera litura hemocytes has been reported. However, how M. bicoloratus parasitism regulates the host signaling pathways to induce DNA fragmentation during apoptosis remains unclear. To address this question, we performed a new RNAseq-based comparative analysis of the hemocytes transcriptomes of non-parasitized and parasitized S. litura. We were able to assemble a total of more than 11.63 Gbp sequence, to yield 20,571 unigenes. At least six main protein families encoded by M. bicoloratus bracovirus are expressed in the parasitized host hemocytes: Ankyrin-repeat, Ben domain, C-type lectin, Egf-like and Mucin-like, protein tyrosine phosphatase. The analysis indicated that during DNA fragmentation and cell death, 299 genes were up-regulated and 2,441 genes were down-regulated. Data on five signaling pathways related with cell death, the gap junctions, Ca2+, PI3K/Akt, NF-κB, ATM/p53 revealed that CypD, which is involved in forming a Permeability Transition Pore Complex (PTPC) to alter mitochondrial membrane permeabilization (MMP), was dramatically up-regulated. The qRT-PCR also provided that the key genes for cell survival were down-regulated under M. bicoloratus parasitism, including those encoding Inx1, Inx2 and Inx3 of the gap junction signaling pathway, p110 subunit of the PI3K/Akt signaling pathway, and the p50 and p65 subunit of the NF-κB signaling pathway. These findings suggest that M. bicoloratus parasitism may regulate host mitochondria to trigger internucleosomal DNA fragmentation. This study will facilitate the identification of immunosuppression-related genes and also improves our understanding of molecular mechanisms underlying polydnavirus-parasitoid-host interaction.
authors.affiliation: School of Life Sciences, Yunnan University, Kunming, P. R. China; Key Laboratory for Animal Genetic Diversity and Evolution of High Education in Yunnan Province, Yunnan University, Kunming, P. R. China.
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.affiliation: School of Life Sciences, Yunnan University, Kunming, P. R. China; Key Laboratory for Animal Genetic Diversity and Evolution of High Education in Yunnan Province, Yunnan University, Kunming, P. R. China.
authors.forename: Zunyu
authors.initials: Z
authors.lastname: Pang
authors.affiliation: School of Life Sciences, Yunnan University, Kunming, P. R. China; Key Laboratory for Animal Genetic Diversity and Evolution of High Education in Yunnan Province, Yunnan University, Kunming, P. R. China.
authors.forename: Wei
authors.initials: W
authors.lastname: Xiao
authors.affiliation: School of Life Sciences, Yunnan University, Kunming, P. R. China; Key Laboratory for Animal Genetic Diversity and Evolution of High Education in Yunnan Province, Yunnan University, Kunming, P. R. China.
authors.forename: Xinyi
authors.initials: X
authors.lastname: Liu
authors.affiliation: School of Life Sciences, Yunnan University, Kunming, P. R. China; Key Laboratory for Animal Genetic Diversity and Evolution of High Education in Yunnan Province, Yunnan University, Kunming, P. R. China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: School of Life Sciences, Yunnan University, Kunming, P. R. China; Key Laboratory for Animal Genetic Diversity and Evolution of High Education in Yunnan Province, Yunnan University, Kunming, P. R. China.
authors.forename: Dongshuai
authors.initials: D
authors.lastname: Yu
authors.affiliation: Shanghai-Ministry of Science and Technology Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai, Shanghai, P. R. China.
authors.forename: Minjun
authors.initials: M
authors.lastname: Yang
authors.affiliation: School of Life Sciences, Yunnan University, Kunming, P. R. China; Key Laboratory for Animal Genetic Diversity and Evolution of High Education in Yunnan Province, Yunnan University, Kunming, P. R. China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Yang
authors.affiliation: School of Life Sciences, Yunnan University, Kunming, P. R. China; Key Laboratory for Animal Genetic Diversity and Evolution of High Education in Yunnan Province, Yunnan University, Kunming, P. R. China.
authors.forename: Jiansheng
authors.initials: J
authors.lastname: Hu
authors.affiliation: School of Life Sciences, Yunnan University, Kunming, P. R. China; Key Laboratory for Animal Genetic Diversity and Evolution of High Education in Yunnan Province, Yunnan University, Kunming, P. R. China.
authors.forename: Kaijun
authors.initials: K
authors.lastname: Luo
mesh_terms: D000818:Animals; D017209:Apoptosis; D002463:Cell Membrane Permeability; D053938:DNA Fragmentation; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006434:Hemocytes / Q000166:cytology / Q000378:metabolism* / Q000469:parasitology; D006790:Host-Parasite Interactions; D007165:Immunosuppression Therapy; D037181:Lectins, C-Type / Q000737:chemistry; D033681:Mitochondrial Membrane Transport Proteins / Q000378:metabolism; D051336:Mitochondrial Membranes; D000083162:Mitochondrial Permeability Transition Pore; D016328:NF-kappa B / Q000378:metabolism; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D015398:Signal Transduction; D018411:Spodoptera / Q000378:metabolism* / Q000469:parasitology; D014158:Transcription, Genetic; D059467:Transcriptome; D014863:Wasps
chemical_list: D037181:Lectins, C-Type; D033681:Mitochondrial Membrane Transport Proteins; D000083162:Mitochondrial Permeability Transition Pore; D016328:NF-kappa B; D019869:Phosphatidylinositol 3-Kinases