A beta-integrin from sea cucumber Apostichopus japonicus exhibits LPS binding activity and negatively regulates coelomocyte apoptosis

作者：Wang, Zhenhui; Shao, Yina; Li, Chenghua^*; Lv, Zhimeng; Wang, Haihong; Zhang, Weiwei; Zhao, Xuelin

来源：Fish & Shellfish Immunology, 2016, 52: 103-110.

DOI：10.1016/j.fsi.2016.03.031

• Apostichopus japonicus
• beta-Integrin
• LPS binding activity
• Cell apoptosis
• siRNA

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 beta-integrin subunit (designated as AjITGB) was cloned from Apostichopus japonicusby 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 beta-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.

• 出版日期2016-5
• 单位宁波大学