title: A β-integrin from sea cucumber Apostichopus japonicus exhibits LPS binding activity and negatively regulates coelomocyte apoptosis.
abstract: Integrins are a family of membrane glycoproteins, which are the major receptors for extracellular matrix and cell-cell adhesion molecules. In this study, a 1038 bp sequence representing the full-length cDNA of a novel β-integrin subunit (designated as AjITGB) was cloned from Apostichopus japonicas by using combined transcriptome sequencing and RACE approaches. The deduced amino acid sequence of AjITGB shared a conserved tripeptide Arg-Gly-Asp (RGD) binding domain with an S-diglyceridecysteine or N-Palm cysteine residue (C(31)), a transmembrane domain, and a β-integrin cytoplasmic domain. Spatial distribution analysis showed that AjITGB was constitutively expressed in all tested tissues with dominant expression in the muscles and weak expression in the respiratory tree. The pathogen Vibrio splendidus challenge and LPS stimulation could both significantly down-regulate the mRNA expression of AjITGB. Functional investigation revealed that recombinant AjITGB displayed higher LPS binding activity but lower binding activity to PGN and MAN. More importantly, knockdown of AjITGB by specific siRNA resulted in the significant promotion of coelomocyte apoptosis in vitro. Results indicated that AjITGB may serve as an apoptosis inhibitor with LPS binding activity during host-pathogen interaction in sea cucumber.
authors.affiliation: School of Marine Sciences, Ningbo University, Ningbo, Zhejiang, 315211, PR China.
authors.forename: Zhenhui
authors.initials: Z
authors.lastname: Wang
authors.affiliation: School of Marine Sciences, Ningbo University, Ningbo, Zhejiang, 315211, PR China.
authors.forename: Yina
authors.initials: Y
authors.lastname: Shao
authors.affiliation: School of Marine Sciences, Ningbo University, Ningbo, Zhejiang, 315211, PR China. Electronic address: lichenghua@nbu.edu.cn.
authors.forename: Chenghua
authors.initials: C
authors.lastname: Li
authors.affiliation: School of Marine Sciences, Ningbo University, Ningbo, Zhejiang, 315211, PR China.
authors.forename: Zhimeng
authors.initials: Z
authors.lastname: Lv
authors.affiliation: School of Marine Sciences, Ningbo University, Ningbo, Zhejiang, 315211, PR China.
authors.forename: Haihong
authors.initials: H
authors.lastname: Wang
authors.affiliation: School of Marine Sciences, Ningbo University, Ningbo, Zhejiang, 315211, PR China.
authors.forename: Weiwei
authors.initials: W
authors.lastname: Zhang
authors.affiliation: School of Marine Sciences, Ningbo University, Ningbo, Zhejiang, 315211, PR China.
authors.forename: Xuelin
authors.initials: X
authors.lastname: Zhao
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism; D007113:Immunity, Innate; D039641:Integrin beta Chains / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology; D000069452:Pathogen-Associated Molecular Pattern Molecules / Q000378:metabolism; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D047528:Stichopus / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D014733:Vibrio / Q000502:physiology
chemical_list: D018076:DNA, Complementary; D039641:Integrin beta Chains; D008070:Lipopolysaccharides; D000069452:Pathogen-Associated Molecular Pattern Molecules; D012333:RNA, Messenger; D011994:Recombinant Proteins
keywords: Apostichopus japonicus; Cell apoptosis; LPS binding activity; siRNA; β-Integrin