CgBlimp-1 inhibits granulocytes proliferation and interleukin production in the immune response of oyster Crassostrea gigas. (May 2023)

• Record Type: Journal Article
• Authors: Li, Qing; Wang, Weilin; Wu, Shasha; Li, Jialuo; Dong, Miren; Wang, Lingling; Song, Linsheng
• Is Part Of: Developmental and comparative immunology. Volume 142(2023)
• Publication Date: 2023-05
• Subjects: B lymphocyte-inducible maturation protein 1 -- Cell proliferation -- Granulocytes -- Cell cycle progression -- Oyster Crassostrea gigas; Immunology -- Periodicals; Developmental immunology -- Periodicals; 616.079
• DOI: 10.1016/j.dci.2023.104652
• Languages: English
• ISSNs: 0145-305X

Abstract

Abstract: B lymphocyte-inducible maturation protein 1 (Blimp-1) is a SET domain and zinc fingers containing transcriptional repressor, which is necessary for regulating the development of many immune cell lineages and keeping immune homeostasis. In the present study, a Blimp-1 homologue (designated as Cg Blimp-1) was identified from oyster Crassostrea gigas, which contained a conserved SET domain and five ZnF_C2H2 domains and shared high homology with Blimp-1 from other species. The mRNA transcripts of Cg Blimp-1 were highly expressed in gill and hepatopancreas. Cg Blimp-1 protein was detected to be specifically expressed in granulocytes. After V . splendidus stimulation, the mRNA expression level of Cg Blimp-1 in haemocytes up-regulated significantly at 24, 48, and 96 h, which was 4.39-fold ( p < 0.05), 7.68-fold ( p < 0.01) and 2.65-fold ( p < 0.05) of that in control group, respectively. When the expression of Cg Blimp-1 was knocked-down in vivo by RNAi, the mRNA expressions of downstream transcription factor Cg Myc-A (1.63-fold of that in control group, p < 0.05) and cell cycle related gene Cg CDK2 (1.70-fold, p < 0.05) increased significantly at 24 h after V . splendidus stimulation. Concomitantly, the ratio of EdU + haemocytes increased notably ( p < 0.01) while the proportion of haemocytes in G0/G1 phase decreased dramatically ( p < 0.001), compared to that in control group. More specifically, the proportion of granulocytes in total haemocytes increased apparently ( p < 0.05) in Cg Blimp-1-RNAi oysters, together with up-regulation ( p < 0.05) of the ratio of EdU + granulocytes and down-regulation ( p < 0.001) of the proportion of granulocytes in G0/G1 phase. Furthermore, the mRNA expression levels of Cg IL17-1, Cg IL17-2 and Cg IL17-4 in haemocytes increased significantly in Cg Blimp-1-RNAi oysters, which was 1.71-fold ( p < 0.05), 144.70-fold ( p < 0.01) and 1.93-fold ( p < 0.05) of that in control group, respectively. Aforementioned results suggested that Cg Blimp-1 could reduce the proliferation of granulocytes by arresting cell cycle in G1/G0 phase and avoid over-expression of interleukin to maintain homeostasis in the immune response of oyster. Highlights: A Blimp-1 homologue ( Cg Blimp-1) was identified from oyster Crassostrea gigas. Cg Blimp-1 was highly expressed in granulocytes, and up-regulated after the stimulation with Vibrio splendidus. Cg Blimp-1 down-regulated Cg Myc-A to attenuate proliferative potential and maintained homeostasis in the immune response.