Btg2, also known as PC3 or TIS21, is a member of the antiproliferative (APRO) gene family [3]. It plays crucial roles in various cellular processes such as cell differentiation, proliferation, DNA damage repair, and apoptosis [3]. It is involved in multiple signal pathways, and its expression can be regulated by factors like microRNA-21 [3]. In the immune system, it helps maintain T cell quiescence [2].

In a mouse model of focal segmental glomerulosclerosis (FSGS), podocyte-specific deletion of Btg2 protected against the onset of proteinuria and glomerulosclerosis in Adriamycin-treated mice [1]. This indicates that Btg2 promotes FSGS via Smad3-dependent podocyte-mesenchymal transition [1]. In muscle stem cells, overexpression and knockdown of Btg2 in primary MuSCs from mice respectively stimulated and prevented MuSCs senescence, suggesting its role as a regulator of MuSC senescence [4].

In conclusion, Btg2 has diverse biological functions including maintaining cell quiescence, influencing cell proliferation and differentiation. Mouse models, especially gene-knockout models in podocytes and muscle stem cells, have revealed its role in FSGS and muscle aging, providing insights into the mechanisms of these diseases and potential therapeutic targets.

References:

1. Dan Hu, Qiong-, Wang, Hong-Lian, Liu, Jian, Lan, Hui-Yao, Wang, Li. 2023. Btg2 Promotes Focal Segmental Glomerulosclerosis via Smad3-Dependent Podocyte-Mesenchymal Transition. In Advanced science (Weinheim, Baden-Wurttemberg, Germany), 10, e2304360. doi:10.1002/advs.202304360. https://pubmed.ncbi.nlm.nih.gov/37749872/

2. Hwang, Soo Seok, Lim, Jaechul, Yu, Zhibin, Li, Hua-Bing, Flavell, Richard A. . mRNA destabilization by BTG1 and BTG2 maintains T cell quiescence. In Science (New York, N.Y.), 367, 1255-1260. doi:10.1126/science.aax0194. https://pubmed.ncbi.nlm.nih.gov/32165587/

3. Mao, Bijing, Zhang, Zhimin, Wang, Ge. 2014. BTG2: a rising star of tumor suppressors (review). In International journal of oncology, 46, 459-64. doi:10.3892/ijo.2014.2765. https://pubmed.ncbi.nlm.nih.gov/25405282/

4. Peng, Baozhou, Chen, Yihan, Wang, Yaning, Wang, Shuaiyu, Zhang, Hongbo. 2023. BTG2 acts as an inducer of muscle stem cell senescence. In Biochemical and biophysical research communications, 669, 113-119. doi:10.1016/j.bbrc.2023.05.098. https://pubmed.ncbi.nlm.nih.gov/37269593/