title: Toxin diversity revealed by a transcriptomic study of Ornithoctonus huwena.
abstract: Spider venom comprises a mixture of compounds with diverse biological activities, which are used to capture prey and defend against predators. The peptide components bind a broad range of cellular targets with high affinity and selectivity, and appear to have remarkable structural diversity. Although spider venoms have been intensively investigated over the past few decades, venomic strategies to date have generally focused on high-abundance peptides. In addition, the lack of complete spider genomes or representative cDNA libraries has presented significant limitations for researchers interested in molecular diversity and understanding the genetic mechanisms of toxin evolution. In the present study, second-generation sequencing technologies, combined with proteomic analysis, were applied to determine the diverse peptide toxins in venom of the Chinese bird spider Ornithoctonus huwena. In total, 626 toxin precursor sequences were retrieved from transcriptomic data. All toxin precursors clustered into 16 gene superfamilies, which included six novel superfamilies and six novel cysteine patterns. A surprisingly high number of hypermutations and fragment insertions/deletions were detected, which accounted for the majority of toxin gene sequences with low-level expression. These mutations contribute to the formation of diverse cysteine patterns and highly variable isoforms. Furthermore, intraspecific venom variability, in combination with variable transcripts and peptide processing, contributes to the hypervariability of toxins in venoms, and associated rapid and adaptive evolution of toxins for prey capture and defense.
authors.affiliation: The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, China.
authors.forename: Yiya
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Huang
authors.affiliation: The State Key Laboratory of Genetic Engineering, Institute of Biomedical Science, Fudan University, Shanghai, China.
authors.forename: Quanze
authors.initials: Q
authors.lastname: He
authors.affiliation: The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, China.
authors.forename: Jinyan
authors.initials: J
authors.lastname: Liu
authors.affiliation: The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, China.
authors.forename: Ji
authors.initials: J
authors.lastname: Luo
authors.affiliation: The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, China.
authors.forename: Li
authors.initials: L
authors.lastname: Zhu
authors.affiliation: The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Lu
authors.affiliation: The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, China.
authors.forename: Pengfei
authors.initials: P
authors.lastname: Huang
authors.affiliation: The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, China.
authors.forename: Xinyi
authors.initials: X
authors.lastname: Chen
authors.affiliation: The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, China.
authors.forename: Xiongzhi
authors.initials: X
authors.lastname: Zeng
authors.affiliation: The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, China.
authors.forename: Songping
authors.initials: S
authors.lastname: Liang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001097:Arachnida / Q000737:chemistry / Q000235:genetics*; D020869:Gene Expression Profiling; D015723:Gene Library; D010802:Phylogeny; D016415:Sequence Alignment; D013111:Spider Venoms / Q000737:chemistry / Q000235:genetics*; D014118:Toxins, Biological / Q000096:biosynthesis* / Q000145:classification / Q000235:genetics
chemical_list: D013111:Spider Venoms; D014118:Toxins, Biological