A vital ubiquitin-conjugating enzyme CgUbe2g1 participated in regulation of immune response of Pacific oyster Crassostrea gigas

Rui Liu; Qi Cheng; Xiaorui Song; Hao Wang; Xiudan Wang; Lingling Wang; Beiwei Zhu; Linsheng Song

doi:10.1016/j.dci.2018.10.014

A vital ubiquitin-conjugating enzyme CgUbe2g1 participated in regulation of immune response of Pacific oyster Crassostrea gigas

Dev Comp Immunol. 2019 Feb:91:132-142. doi: 10.1016/j.dci.2018.10.014. Epub 2018 Oct 30.

Authors

Rui Liu¹, Qi Cheng², Xiaorui Song³, Hao Wang¹, Xiudan Wang¹, Lingling Wang⁴, Beiwei Zhu⁵, Linsheng Song⁶

Affiliations

¹ Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China.
² Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China; School of Food Science and Technology, Dalian Polytechnic University, Dalian, 116034, China.
³ Laboratory of Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235, China; Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China.
⁴ Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China.
⁵ School of Food Science and Technology, Dalian Polytechnic University, Dalian, 116034, China.
⁶ Laboratory of Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235, China; Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China. Electronic address: lshsong@dlou.edu.cn.

PMID: 30389518
DOI: 10.1016/j.dci.2018.10.014

Abstract

As an important post-translational protein modification, ubiquitination has been demonstrated to play a vital role in immune response of vertebrates. Ubiquitin (Ub)-conjugating enzyme E2 is the "heart" of ubiquitination, which is responsible for Ub cellular signaling and substrate modification. In the present study, an Ub-conjugating enzyme E2 (designed as CgUbe2g1) was identified from oyster Crassostrea gigas, and its regulation in the immune response against lipopolysaccharide (LPS) stimulation was investigated. CgUbe2g1 encoded a polypeptide of 168 amino acids with the predicted molecular mass of 19.20 kDa and contained conserved catalytic 'Ubc' domains. It shared a higher similarity with the known UBC2G1 type E2s and was closely clustered with the type E2s identified from invertebrates in the phylogenetic assay. The mRNA transcripts of CgUbe2g1 were mainly distributed in hemocyte, mantle, hepatopancreas and male gonad of C. gigas. CgUbe2g1 protein was found to be colocalized with Ub around the nucleus of oyster hemocyte. The recombinant CgUbe2g1 protein (rCgUbe2g1) could activate the ubiquitination in vitro by binding both activated and un-activated Ub. The expressions of inflammation-related factors TNF-α and NF-κB in CgUbe2g1 transfected cells were both significantly up-regulated after LPS stimulation, which were 12.9-fold at 3 h (p < 0.01) and 2.3-fold at 6 h (p < 0.01) of that in negative control group, respectively. The phagocytic rate of hemocyte and the ROS level in hemocyte were both significantly decreased (p < 0.01), while the apoptosis rate was significantly increased (p < 0.01) after CgUbe2g1 mRNA was interfered. These results demonstrated that Ub-conjugating enzyme CgUbe2g1 was involved in the innate immune response of oyster against invading pathogen, which might play important roles in the activation of inflammatory response and regulation of cellular immune response.

Keywords: Cellular immunity; Crassostrea gigas; Inflammatory response; NF-κB pathway; Ub-conjugating enzyme E2; Ubiquitination.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Apoptosis
Cells, Cultured
Cloning, Molecular
Crassostrea / immunology*
Hemocytes / physiology*
Humans
Immunity, Innate
NF-kappa B / metabolism
Phylogeny
Transcriptome
Tumor Necrosis Factor-alpha / metabolism
Ubiquitin-Conjugating Enzymes / genetics*
Ubiquitin-Conjugating Enzymes / metabolism
Ubiquitination

Substances

NF-kappa B
Tumor Necrosis Factor-alpha
UBE2G1 protein, human
Ubiquitin-Conjugating Enzymes