GATA-3 in Atlantic salmon (Salmo salar): Tissue distribution and its regulation of IL-4/13a promoter

• Published in: Frontiers in Cellular and Infection Microbiology
• Main Authors: Chi, Heng, Meng, Xianghu, Dalmo, Roy Ambli
• Other Authors: National Key Research and Development Program of China, National Natural Science Foundation of China
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Frontiers Media SA 2022
• Subjects: Infectious Diseases; Microbiology (medical); Immunology; Microbiology; Gata; Pillar; Atlantic salmon; Salmo salar
• Online Access: http://dx.doi.org/10.3389/fcimb.2022.1063600; https://www.frontiersin.org/articles/10.3389/fcimb.2022.1063600/full

GATA3 is a transcription factor that plays an important role in T cell lineage differentiation and T-helper 2 (Th2) type immune responses. In this study, we developed two rat antibodies against Atlantic salmon GATA-3 (anti-r Ss GATA-3a and anti-r Ss GATA-3b, respectively). The western blotting and immunofluorescence results showed that anti-r Ss GATA-3b antibodies recognized endogenous Ss GATA-3 proteins, while the anti-r Ss GATA-3a antibodies did not bind Ss GATA-3. Immunohistochemical analysis revealed that Ss GATA-3 positive cells were detected in all tissues tested, with relatively high number of immune reactive cells in the gills and spleen. Furthermore, the immunohistochemical study revealed that Ss GATA-3 was expressed in pillar cells, epithelial cells, chondrocytes, perichondrium cells, and some undifferentiated basal cells. In addition, we determined 577 bp of the upstream promoter sequence of Ss IL-4/13a and found four motifs that matched Ss GATA-3 binding sites. The promoter regions of Ss IL-4/13a were assessed by transfecting four deletion reporter constructs and Ss GATA-3 overexpression plasmids. The result showed that Ss GATA-3 enhanced the activity of Ss IL-4/13a promoters within the region ranging from -317 to -302 bp upstream of the transcriptional start site. Antibodies against Th2 markers such as GATA-3 are valuable in addressing the diversity of T cell responses in fish.