Identification, characterization, and agglutinating activity of a novel C-type lectin domain family 3 member B (CLEC3B) discovered in golden pompano, Trachinotus ovatus

Ming Luo; Sanghyok Ri; Longlong Liu; Songnam Ri; Yongchol Kim; Tongchol Kim; Kwangjin Ju; Weishang Zhou; Difei Tong; Wei Shi; Guangxu Liu

doi:10.1016/j.fsi.2023.108988

Identification, characterization, and agglutinating activity of a novel C-type lectin domain family 3 member B (CLEC3B) discovered in golden pompano, Trachinotus ovatus

Fish Shellfish Immunol. 2023 Sep:140:108988. doi: 10.1016/j.fsi.2023.108988. Epub 2023 Aug 3.

Authors

Ming Luo¹, Sanghyok Ri², Longlong Liu¹, Songnam Ri³, Yongchol Kim³, Tongchol Kim², Kwangjin Ju⁴, Weishang Zhou⁵, Difei Tong⁵, Wei Shi⁵, Guangxu Liu⁶

Affiliations

¹ Hainan Provincial Key Laboratory of Tropical Maricultural Technologies, Hainan Academy of Ocean and Fisheries Sciences, Haikou, 571126, PR China.
² College of Animal Sciences, Zhejiang University, Hangzhou, 310058, PR China; College of Life Science, Kim Hyong Jik University of Education, Pyongyang, 99903, Democratic People's Republic of Korea.
³ College of Life Science, Kim Hyong Jik University of Education, Pyongyang, 99903, Democratic People's Republic of Korea.
⁴ College of Animal Sciences, Zhejiang University, Hangzhou, 310058, PR China; College of Aquaculture, Wonsan Fisheries University, Wonsan, 999093, Democratic People's Republic of Korea.
⁵ College of Animal Sciences, Zhejiang University, Hangzhou, 310058, PR China.
⁶ College of Animal Sciences, Zhejiang University, Hangzhou, 310058, PR China. Electronic address: guangxu_liu@zju.edu.cn.

PMID: 37541635
DOI: 10.1016/j.fsi.2023.108988

Abstract

The lectins are a large family of carbohydrate-binding proteins that play important roles in the innate immune response of various organisms. Although C-type lectin domain family 3 member B (CLEC3B), an important member of C-type lectin, has been well documented in humans and several other higher vertebrates, little is currently known about this molecule in economically important marine fish species. In this study, through transcriptomic and BLAST screening, a novel CLEC3B gene was identified in the golden pompano (Trachinotus ovatus). The T. ovatus CLEC3B (ToCLEC3B) was subsequently characterized by bioinformatic analysis and compared with those reported in other species. In addition, the expression patterns of ToCLEC3B in different tissues under normal condition and at different times post pathogen challenge were assessed. Furthermore, the agglutinating activity of ToCLEC3B with and without Ca²⁺ against different bacteria and blood cells of donor species were verified using the recombinant T. ovatus CLEC3B (rToCLEC3B). Our results demonstrated that ToCLEC3B is a Ca²⁺-dependent galactose-binding lectin with a single copy of carbohydrate recognition domain (CRD). Similar to CLEC3B reported in other species, the CRD domain of ToCLEC3B consists of two α-helices, six β-sheets, and four loops, forming two Ca²⁺- and a galactose-binding sites. According to the phylogenetic analysis, the ToCLEC3B was highly similar (similarity at 95.00%) to that of its relative, the greater amberjack (Seriola dumerili). The expression of ToCLEC3B was detected in all tissues examined under normal condition and was significantly up-regulated by injection of pathogenic microbes. In addition, the rToCLEC3B exhibited strong agglutinating activity against different bacteria and blood cells of donor species in the presence of Ca²⁺. Our results indicate that ToCLEC3B is a constitutive and inducible acute-phase immune factor in the host's innate immune response of T. ovatus.

Keywords: Agglutinating activity; C-type lectin; CLEC3B; Innate immunity; Trachinotus ovatus.

MeSH terms

Animals
Fish Proteins* / chemistry
Fishes
Humans
Immunity, Innate / genetics
Perciformes*
Phylogeny

Substances

Fish Proteins