1.Key Laboratory of Cultivation and High-Value Utilization of Marine Organisms in Fujian Province，Fisheries Research Institute of Fujian，Xiamen 361013，China；2.College of Ocean Food and Biological Engineering，Jimei University，Xiamen 361021，China；3.College of Ocean and Earth Sciences，Xiamen University，Xiamen 361102，China
Abstract: In order to investigate the immune function of the peptidoglycan recognition protein HdhPGRP-SC2-like gene in disk abalone (Haliotisdiscushannai), the full-length cDNA sequence of HdhPGRP-SC2-like gene was cloned by RACE technology, and tissue distribution of HdhPGRP-SC2-like gene was analyzed in the disk abalone by real-time fluorescent quantitative PCR(qPCR). The recombinant protein rHdhPGRP-SC2-like was obtained by prokaryotic expression, and its amidase activity and immune characteristics were verified. The results showed that the cDNA of the HdhPGRP-SC2-like gene was 938 bp in length, with an open reading frame of 780 bp, encoding 260 amino acids and containing the conserved PGRP and Ami_2 structural domains. HdhPGRP-SC2-like gene as a short type PGRP had high similarity with the closely related species PGRP of mollusks. qPCR analysis showed that HdhPGRP-SC2-like mRNA was expressed in all tissues of the disk abalone, with the maximal expression level in gill, a certain amount of expression level in mantle and digestive gland, and the minimal content in foot and hemocyte. The prokaryotic expression vector pET-28a(+)-HdhPGRP-SC2-like was further constructed, and the recombinant protein rHdhPGRP-SC2-like gene was obtained by induction of expression, isolation, and purification. The recombinant protein had peptidoglycan binding activity and showed amidase activity in the presence of Zn2+. The finding indicated that HdhPGRP-SC2-like gene binded bacterial peptidoglycan components and played an important role in the immune defence against invading bacteria.
2023, Vol. 38 
