Molecular characterization and gene expression of pattern recognition receptors in brown-marbled grouper ( Epinephelus fuscoguttatus) fingerlings responding to vibriosis infection

• Published in: DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY
• Main Authors: Alipiah, Norfarrah Mohamed; Salleh, Annas; Sarizan, Nur Maisarah; Ikhsan, Natrah
• Format: Article
• Language: English
• Published: ELSEVIER SCI LTD 2024
• Subjects: Fisheries; Immunology; Veterinary Sciences; Zoology
• Online Access: https://www-webofscience-com.uitm.idm.oclc.org/wos/woscc/full-record/WOS:001309042800001
• ISSN: 0145-305X; 1879-0089
• DOI: 10.1016/j.dci.2024.105253

The pathogen recognition system involves receptors and genes that play a crucial role in activating innate immune response in brown-marbled grouper ( Epinephelus fuscoguttatus) ) as a control agent against various infections including vibriosis. Here, we report the molecular cloning of partial open reading frames, sequences characterization, and expression profiles of Pattern Recognition Receptors (PRRs) in brown-marbled grouper. The PRRs, namely pglyrp5, , tlr5, , ctlD, and ctlE in brown-marbled grouper, possess conserved domains and showed shared evolutionary relationships with other fishes, humans, mammals, birds, reptilians, amphibians, and insects. In infection experiments, up to 50% mortality was found in brown-marbled grouper fingerlings infected with Vibrio alginolyticus compared to 27% mortality infected Vibrio parahaemolyticus and 100% survival of control groups. It is also demonstrated that all four PRRs had higher expression in samples infected with V. alginolyticus compared to V. parahaemolyticus. . This PRRs gene expression analysis revealed that all four PRRs expressed rapidly at 4-h post-inoculation even though the Vibrio count was only detected earliest at 12-h post-inoculation in samples. The highest expression recorded was from V . alginolyticus inoculated fish spleen with up to 73-fold change for pglyrp5 gene, followed by 14 to 38-fold expression for the same treatment in spleen, head kidney, and blood samples for other PRRs, namely tlr5, , ctlD, and ctlE genes. Meanwhile less than a 10% increase in expression of all four genes was detected in spleen, head kidney, and blood samples inoculated with V. parahaemolyticus. . These findings indicated that pglyrp5, , tlr5, , ctlD, and ctlE play important roles in the early immune response to vibriosis infected, brown-marbled grouper fingerlings.