Identification and characterization of two long-type peptidoglycan recognition proteins, PGRP-L1 and PGRP-L2, in the orange-spotted grouper, Epinephelus coioides

Jing Hou; Wei Hao; Min Chang Li; Zhen Gan; Shan Nan Chen; Yi Shan Lu; Li Qun Xia

doi:10.1016/j.fsi.2023.108580

Identification and characterization of two long-type peptidoglycan recognition proteins, PGRP-L1 and PGRP-L2, in the orange-spotted grouper, Epinephelus coioides

Fish Shellfish Immunol. 2023 Mar:134:108580. doi: 10.1016/j.fsi.2023.108580. Epub 2023 Feb 14.

Authors

Jing Hou¹, Wei Hao², Min Chang Li², Zhen Gan³, Shan Nan Chen⁴, Yi Shan Lu⁵, Li Qun Xia⁶

Affiliations

¹ School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, Shandong Province, 266109, China; Guangdong Provincial Engineering Research Center for Aquatic Animal Health Assessment, Shenzhen Public Service Platform for Evaluation of Marine Economic Animal Seedings, Shenzhen Institute of Guangdong Ocean University, Shenzhen, 518120, Guangdong, China; Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, College of fishery, Guangdong Ocean University, Zhanjiang, 524025, Guangdong, China.
² School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, Shandong Province, 266109, China.
³ Guangdong Provincial Engineering Research Center for Aquatic Animal Health Assessment, Shenzhen Public Service Platform for Evaluation of Marine Economic Animal Seedings, Shenzhen Institute of Guangdong Ocean University, Shenzhen, 518120, Guangdong, China; Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, College of fishery, Guangdong Ocean University, Zhanjiang, 524025, Guangdong, China.
⁴ State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.
⁵ Guangdong Provincial Engineering Research Center for Aquatic Animal Health Assessment, Shenzhen Public Service Platform for Evaluation of Marine Economic Animal Seedings, Shenzhen Institute of Guangdong Ocean University, Shenzhen, 518120, Guangdong, China; Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, College of fishery, Guangdong Ocean University, Zhanjiang, 524025, Guangdong, China. Electronic address: fishdis@163.com.
⁶ Guangdong Provincial Engineering Research Center for Aquatic Animal Health Assessment, Shenzhen Public Service Platform for Evaluation of Marine Economic Animal Seedings, Shenzhen Institute of Guangdong Ocean University, Shenzhen, 518120, Guangdong, China; Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, College of fishery, Guangdong Ocean University, Zhanjiang, 524025, Guangdong, China. Electronic address: xialq@gdou.edu.cn.

PMID: 36796596
DOI: 10.1016/j.fsi.2023.108580

Abstract

Peptidoglycan recognition proteins (PGRPs) play an important role in innate immunity by recognizing components of pathogenic bacteria (such as peptidoglycan, PGN) and are evolutionarily conserved pattern recognition receptors (PRRs) in both invertebrates and vertebrates. In the present study, two long-type PGRPs (designed as Eco-PGRP-L1 and Eco-PGRP-L2) were identified in orange-spotted grouper (Epinephelus coioides), which is a major economic species cultured in Asia. The predicted protein sequences of both Eco-PGRP-L1 and Eco-PGRP-L2 contain a typical PGRP domain. Eco-PGRP-L1 and Eco-PGRP-L2 exhibited organ/tissue-specific expression patterns. An abundant expression of Eco-PGRP-L1 was observed in pyloric caecum, stomach and gill, whereas a highest expression level of Eco-PGRP-L2 was found in head kidney, spleen, skin and heart. In addition, Eco-PGRP-L1 is distributed in the cytoplasm and nucleus, while Eco-PGRP-L2 is mainly localized in cytoplasm. Both Eco-PGRP-L1 and Eco-PGRP-L2 were induced following the stimulation of PGN and have PGN binding activity. In addition, functional analysis revealed that Eco-PGRP-L1 and Eco-PGRP-L2 possess antibacterial activity against Edwardsiella tarda. These results may contribute to understand the innate immune system of orange-spotted grouper.

Keywords: Antibacterial activity; Orange-spotted grouper; PGRP; Peptidoglycan recognition proteins.

MeSH terms

Amino Acid Sequence
Animals
Bass*
Carrier Proteins / genetics
Peptidoglycan / metabolism
Phylogeny

Substances

peptidoglycan recognition protein
Carrier Proteins
Peptidoglycan