Toll-interacting protein is activated by the transcription factor GATA1 and Sp1 to negatively regulate NF-κB and MAPK pathways in the Japanese eel (Anguilla japonica)

Tianyu Wang; Hui Ge; Peng Lin; Yilei Wang; Xiaojian Lai; Pengyun Chen; Fuyan Li; Jianjun Feng

doi:10.1016/j.fsi.2024.109561

Toll-interacting protein is activated by the transcription factor GATA1 and Sp1 to negatively regulate NF-κB and MAPK pathways in the Japanese eel (Anguilla japonica)

Fish Shellfish Immunol. 2024 Apr 16:149:109561. doi: 10.1016/j.fsi.2024.109561. Online ahead of print.

Authors

Tianyu Wang¹, Hui Ge², Peng Lin¹, Yilei Wang¹, Xiaojian Lai¹, Pengyun Chen¹, Fuyan Li¹, Jianjun Feng³

Affiliations

¹ Key Laboratory of Healthy Mariculture for the East China Sea, Ministry of Agriculture and Rural Affairs, Fisheries College, Jimei University, Xiamen, Fujian Province, 361021, China; Engineering Research Center of the Modern Technology for Eel Industry, Ministry of Education, Fisheries College, Jimei University, Xiamen, Fujian Province, 361021, China.
² The Open Program of Key Laboratory of Cultivation and High-Value Utilization of Marine Organisms in Fujian Province, Xiamen 361000, China.
³ Key Laboratory of Healthy Mariculture for the East China Sea, Ministry of Agriculture and Rural Affairs, Fisheries College, Jimei University, Xiamen, Fujian Province, 361021, China; The Open Program of Key Laboratory of Cultivation and High-Value Utilization of Marine Organisms in Fujian Province, Xiamen 361000, China; Engineering Research Center of the Modern Technology for Eel Industry, Ministry of Education, Fisheries College, Jimei University, Xiamen, Fujian Province, 361021, China. Electronic address: Fengjj@jmu.edu.cn.

PMID: 38636738
DOI: 10.1016/j.fsi.2024.109561

Abstract

Toll-interacting protein (Tollip) serves as a crucial inhibitory factor in the modulation of Toll-like receptor (TLR)-mediated innate immunological responses. The structure and function of Tollip have been well documented in mammals, yet the information in teleost remained limited. This work employed in vitro overexpression and RNA interference in vivo and in vitro to comprehensively examine the regulatory effects of AjTollip on NF-κB and MAPK signaling pathways. The levels of p65, c-Fos, c-Jun, IL-1, IL-6, and TNF-α were dramatically reduced following overexpression of AjTollip, whereas knocking down AjTollip in vivo and in vitro enhanced those genes' expression. Protein molecular docking simulations showed AjTollip interacts with AjTLR2, AjIRAK4a, and AjIRAK4b. A better understanding of the transcriptional regulation of AjTollip is crucial to elucidating the role of Tollip in fish antibacterial response. Herein, we cloned and characterized a 2.2 kb AjTollip gene promoter sequence. The transcription factors GATA1 and Sp1 were determined to be associated with the activation of AjTollip expression by using promoter truncation and targeted mutagenesis techniques. Collectively, our results indicate that AjTollip suppresses the NF-κB and MAPK signaling pathways, leading to the decreased expression of the downstream inflammatory factors, and GATA1 and Sp1 play a vital role in regulating AjTollip expression.

Keywords: Anguilla japonica; Promoter; Protein docking; RNAi; Tollip.