CLIC2α Chloride Channel Orchestrates Immunomodulation of Hemocyte Phagocytosis and Bactericidal Activity in Crassostrea gigas

• Published in: iScience
• Main Authors: Xiangyu Zhang, Fan Mao, Nai-Kei Wong, Yongbo Bao, Yue Lin, Kunna Liu, Jun Li, Zhiming Xiang, Haitao Ma, Shu Xiao, Yang Zhang, Ziniu Yu
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2020
• Subjects: Cell Biology; Immunology; Microbiology; Science; Q; Pacific; Crassostrea gigas; Pacific oyster
• Online Access: https://doi.org/10.1016/j.isci.2020.101328; https://doaj.org/article/7cb372639c0845ab8564334bc1949112

Summary: Chloride ion plays critical roles in modulating immunological interactions. Herein, we demonstrated that the anion channel CLIC2α mediates Cl− flux to regulate hemocytes functions in the Pacific oyster (Crassostrea gigas). Specifically, during infection by Vibrio parahemolyticus, chloride influx was activated following onset of phagocytosis. Phosphorylation of Akt was stimulated by Cl− ions entering host cells, further contributing to signal transduction regulating internalization of bacteria through the PI3K/Akt signaling pathway. Concomitantly, Cl− entered phagosomes, promoted the acidification and maturation of phagosomes, and contributed to production of HOCl to eradicate engulfed bacteria. Finally, genomic screening reveals CLIC2α as a major Cl− channel gene responsible for regulating Cl− influx in oysters. Knockdown of CLIC2α predictably impeded phagosome acidification and restricted bacterial killing in oysters. In conclusion, our work has established CLIC2α as a prominent regulator of Cl− influx and thus Cl− function in C. gigas in bacterial infection contexts.