Cmip, also known as C-Maf-inducing protein, plays diverse roles in biological processes. It is involved in multiple signaling pathways, such as those related to T-cell activation, and has been associated with the pathophysiology of various diseases. Genetic models, especially knockout (KO) and conditional knockout (CKO) mouse models, can be valuable for studying its function [1-10].

In T-cells, CMIP acts as a negative regulator of signaling. Transgenic expression of CMIP drives T-cells towards a naïve phenotype, inhibiting the activation of Src kinases Fyn and Lck after CD3/CD28 costimulation and blocking the recruitment of LAT and lipid raft markers at the TCR engagement site [1].

In podocytes, overproduction of CMIP downregulates the Wilms tumor 1 suppressor gene (WT1) through preventing NF-κB-mediated transcriptional activation and targeting WT1 to proteasome degradation. Intravenous injection of Cmip-siRNA prevented the repression of Wt1 in a mouse model of lipopolysaccharides-induced proteinuria [2].

In non-alcoholic fatty liver disease (NAFLD), DNA methyltransferase (Dnmt) 1 and Tet methylcytosine dioxygenase 2 (Tet2)-mediated changes in Cmip methylation regulate the development of NAFLD by controlling the Gbp2-Pparγ-CD36 axis. Intravenous Cmip siRNA injection ameliorated NAFLD pathogenic features in ob/ob mice [3].

In conclusion, CMIP is involved in multiple biological functions including T-cell signaling regulation, WT1 expression control in podocytes, and the development of NAFLD. Studies using KO/CKO mouse models or siRNA-mediated knockdown in mice have provided insights into its role in these disease-related processes, highlighting its potential as a therapeutic target in T-cell-related disorders, podocyte diseases, and NAFLD.