Selenos, also known as selenoprotein S, is a small, intrinsically disordered membrane protein. It is mainly known for its role in the ER-associated degradation (ERAD) pathway, extracting misfolded proteins from the ER for proteasomal degradation. Additionally, it is involved in inflammatory processes, cellular stress response, protein quality control, and signaling pathways, and is crucial in maintaining redox homeostasis in the endoplasmic reticulum (ER) [2,4].

In yellow catfish, the HSF1-SELENOS pathway mediates dietary inorganic Se-induced lipogenesis via up-regulating PPARγ expression. Blocking SELENOS by RNA interference demonstrated its critical role in Se-induced lipid accumulation [1]. In colon cancer cells, knocking down SELENOS sensitized ROS-mediated anti-tumor effects of regorafenib, suggesting its potential role in cancer treatment [5]. In brain lower-grade glioma (LGG), siRNA-mediated knockdown of SELENOS reduced the proliferation, viability, invasion and migration of LGG cells, and induced apoptosis, indicating SELENOS as a potential prognostic marker and therapeutic target [3].

In conclusion, Selenos plays diverse roles in biological processes such as lipid metabolism and protein quality control. Studies using loss-of-function methods like RNA interference and siRNA-mediated knockdown in different models have revealed its significance in diseases including lipid-related disorders and cancers, providing insights into potential therapeutic strategies.

References:

1. Zhang, Dian-Guang, Xu, Xiao-Jian, Pantopoulos, Kostas, Zheng, Hua, Luo, Zhi. 2022. HSF1-SELENOS pathway mediated dietary inorganic Se-induced lipogenesis via the up-regulation of PPARγ expression in yellow catfish. In Biochimica et biophysica acta. Gene regulatory mechanisms, 1865, 194802. doi:10.1016/j.bbagrm.2022.194802. https://pubmed.ncbi.nlm.nih.gov/35248747/

2. Ghelichkhani, Farid, Gonzalez, Fabio A, Kapitonova, Mariia A, Cheng, Rujin, Rozovsky, Sharon. 2022. Selenoprotein S: A versatile disordered protein. In Archives of biochemistry and biophysics, 731, 109427. doi:10.1016/j.abb.2022.109427. https://pubmed.ncbi.nlm.nih.gov/36241082/

3. Wang, Yuetong, Qu, Kai, Xia, Zengrun, Ke, Zunhua, Zhang, Rongqiang. 2024. Selenoprotein S (SELENOS) is a potential prognostic biomarker for brain lower grade glioma. In Journal of trace elements in medicine and biology : organ of the Society for Minerals and Trace Elements (GMS), 86, 127539. doi:10.1016/j.jtemb.2024.127539. https://pubmed.ncbi.nlm.nih.gov/39378668/

4. Shi, Zhan, Han, Ziyu, Chen, Jingyi, Zhou, Ji-Chang. 2024. Endoplasmic reticulum-resident selenoproteins and their roles in glucose and lipid metabolic disorders. In Biochimica et biophysica acta. Molecular basis of disease, 1870, 167246. doi:10.1016/j.bbadis.2024.167246. https://pubmed.ncbi.nlm.nih.gov/38763408/

5. Yu, Yun, Wu, Tao, Zhang, Xiaodong, Li, Shaotang, Cui, Ri. 2023. Regorafenib activates oxidative stress by inhibiting SELENOS and potentiates oxaliplatin-induced cell death in colon cancer cells. In European journal of pharmacology, 957, 175986. doi:10.1016/j.ejphar.2023.175986. https://pubmed.ncbi.nlm.nih.gov/37598924/