title: Molecular cloning, characterization and expression analysis of cathepsin A gene in Chinese mitten crab, Eriocheir sinensis.
abstract: Cathepsins, a superfamily of hydrolytic enzymes produced and enclosed within lysosomes, function in immune response in vertebrates; however, their function within the innate immune system of invertebrates remains largely unknown. Therefore, we investigated the immune functionality of cathepsin A (catA) in Chinese mitten crab (Eriocheir sinensis), a commercially important and disease vulnerable aquaculture species. The full length catA cDNA (2200 bp) was cloned via PCR based upon an initial expressed sequence tag (EST) isolated from a hepatopancreatic cDNA library. The catA cDNA contained a 1398 bp open reading frame (ORF) that encoded a putative 465 amino acid (aa) protein. Comparisons with other reported vertebrate cathepsins sequences revealed percent identity range from 48 to 51%. CatA mRNA expression in E. sinensis was (a) tissue-specific, with the highest expression observed in gill and (b) responsive in hemocytes to a Vibrio anguillarum challenge, with peak exposure observed 12 h post-injection. Collectively, data demonstrate the successful isolation of catA from the Chinese mitten crab, and its involvement in the innate immune system of an invertebrate.
authors.affiliation: School of Life Science, East China Normal University, North Zhong-Shan Road, Shanghai, China.
authors.forename: Wei-Wei
authors.initials: WW
authors.lastname: Li
authors.forename: Lin
authors.initials: L
authors.lastname: He
authors.forename: Xing-Kun
authors.initials: XK
authors.lastname: Jin
authors.forename: Hui
authors.initials: H
authors.lastname: Jiang
authors.forename: Li-Li
authors.initials: LL
authors.lastname: Chen
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.forename: Qun
authors.initials: Q
authors.lastname: Wang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003386:Brachyura / Q000235:genetics / Q000378:metabolism*; D043402:Cathepsin A / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D020224:Expressed Sequence Tags; D015723:Gene Library; D008969:Molecular Sequence Data; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment
chemical_list: D043402:Cathepsin A