Molecular control of induced- thermogenesis in skeletal muscle cells in culture

• Grant number: 25/18049-3
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: October 01, 2025
• End date: August 31, 2029
• Field of knowledge: Biological Sciences - Biochemistry - Molecular Biology
• Principal Investigator: Leonardo dos Reis Silveira
• Grantee: Ana Caroline Pimentel de Oliveira
• Host Institution: Instituto de Biologia (IB). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 23/08207-5 - New road to thermogenesis: targeting nuclear receptor Nr2f6 in skeletal muscle, AP.TEM

Abstract

Transcription factors (TFs) regulate specific gene expression programs and play a key role in maintaining metabolic homeostasis. Dysregulation of TFs is directly associated with metabolic diseases such as obesity, diabetes, and cancer. To identify novel TFs that might regulate energy metabolism, we initially conducted a large-scale bioinformatic screening of public datasets (RNAseq and ChIPseq from NCBI). This analysis revealed that the orphan nuclear receptor Nr2f6 is significantly downregulated in skeletal muscle andadipocytes of mice exposed to cold or physical exercise - conditions known to activate thermogenesis. To further investigate its role, we performed Nr2f6 knockdown in C2C12 cells, followed by RNA sequencing. The results revealed a robust upregulation of genes involved in muscle contraction, calcium handling, mitochondrial metabolism, and cellular differentiation - including Sln, Serca1/2, Ryr1, and Slc25a4, all key players in non-shivering thermogenesis. Promoter analysis confirmed the presence of Nr2f6 response elements in these genes. Additionally, Nr2f6 silencing increased AMPK phosphorylation and improved insulin sensitivity, indicating a shift toward a more oxidative and thermogenic phenotype. These findings strongly suggest that Nr2f6 functions as a negative regulator of thermogenesis in skeletal muscle. Based on this, we propose to deeply explore the molecular role of Nr2f6 in regulating thermogenic processes by integrating transcriptomic, proteomic, and mitochondrial functional analyses. We will also develop lentiviral reporter systems to screen for small molecules capable of modulating Nr2f6 activity. The outcomes of this study may provide novel insights and therapeutic targets for combating obesity and related metabolic disorders. (AU)