Scavenger receptor class B type I (SR-BI) in Ruditapes philippinarum: A versatile receptor with multiple functions

Dinglong Yang; Yijing Han; Lizhu Chen; Yongliang Liu; Ruiwen Cao; Qing Wang; Jianmin Zhao

doi:10.1016/j.fsi.2019.03.009

Scavenger receptor class B type I (SR-BI) in Ruditapes philippinarum: A versatile receptor with multiple functions

Fish Shellfish Immunol. 2019 May:88:328-334. doi: 10.1016/j.fsi.2019.03.009. Epub 2019 Mar 8.

Authors

Dinglong Yang¹, Yijing Han², Lizhu Chen³, Yongliang Liu⁴, Ruiwen Cao², Qing Wang¹, Jianmin Zhao⁵

Affiliations

¹ Muping Coastal Environment Research Station, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, PR China; Research and Development Center for Efficient Utilization of Coastal Bioresources, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, PR China.
² Muping Coastal Environment Research Station, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China.
³ Shandong Marine Resource and Environment Research Institute, Yantai, 264006, PR China.
⁴ Muping Coastal Environment Research Station, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, PR China.
⁵ Muping Coastal Environment Research Station, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, PR China; Research and Development Center for Efficient Utilization of Coastal Bioresources, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, PR China; Center for Ocean Mega-science, Chinese Academy of Sciences, Qingdao, Shandong, 266071, PR China. Electronic address: jmzhao@yic.ac.cn.

PMID: 30858096
DOI: 10.1016/j.fsi.2019.03.009

Abstract

In the present study, a scavenger receptor class B type I (designed as RpSR-BI) was cloned and characterized from manila clam Ruditapes philippinarum. The full-length cDNA of RpSR-BI was of 2000 bp, containing an open reading frame (ORF) of 1515 bp. Multiple alignments and phylogenetic analysis strongly suggested that RpSR-BI was a member of the scavenger receptors family. The mRNA transcript of RpSR-BI was constitutively expressed in all tested tissues, and mainly expressed in hepatopancreas and hemocytes. Generally, Vibrio anguillarum or Micrococcus luteus challenge induced the expression of RpSR-BI transcripts in hemocytes of manila clams. Recombinant protein of RpSR-BI (rRpSR-BI) could bind lipopolysaccharides, peptidoglycan and glucan, but not chitin in vitro. Coinciding with the PAMPs binding assay, a broad agglutination spectrum was displayed by rRpSR-BI including Gram-positive bacteria and Gram-negative bacteria. Moreover, rRpSR-BI could enhance the phagocytosis and chemotaxis of hemocytes. These results showed that RpSR-BI functioned as a pattern recognition receptor (PRR) with distinct recognition spectrum, and also as an opsonin involved in the innate immune response of R. philippinarum.

Keywords: Immune recognition; Pattern recognition receptor; Ruditapes philippinarum; Scavenger receptor.

MeSH terms

Agglutination Tests
Animals
Bivalvia / immunology*
Bivalvia / microbiology
Gram-Negative Bacteria
Gram-Positive Bacteria
Hemocytes / metabolism
Hepatopancreas / metabolism
Immunity, Innate / genetics
Pathogen-Associated Molecular Pattern Molecules / pharmacology
Phylogeny
Receptors, Pattern Recognition / metabolism*
Receptors, Scavenger / genetics
Receptors, Scavenger / immunology*

Substances

Pathogen-Associated Molecular Pattern Molecules
Receptors, Pattern Recognition
Receptors, Scavenger