A c-Myc-SIRT1 feedback loop regulates cell growth and transformation.
The protein deacetylase SIRT1 has been implicated in a variety of cellular functions, including development, cellular stress responses, and metabolism. Increasing evidence suggests that similar to its counterpart, Sir2, in yeast, Caenorhabditis elegans, and Drosophila melanogaster, SIRT1 may function to regulate life span in mammals. However, SIRT1's role in cancer is unclear. During our investigation of SIRT1, we found that c-Myc binds to the SIRT1 promoter and induces SIRT1 expression. However, SIRT1 interacts with and deacetylates c-Myc, resulting in decreased c-Myc stability. As a consequence, c-Myc's transformational capability is compromised in the presence of SIRT1. Overall, our experiments identify a c-Myc-SIRT1 feedback loop in the regulation of c-Myc activity and cellular transformation, supporting/suggesting a role of SIRT1 in tumor suppression.
Division of Oncology Research, Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA.
Jian
J
Yuan
Katherine
K
Minter-Dykhouse
Zhenkun
Z
Lou
D000107:Acetylation; D000818:Animals; D002471:Cell Transformation, Neoplastic; D005246:Feedback; D005786:Gene Expression Regulation; D006801:Humans; D008297:Male; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D016271:Proto-Oncogene Proteins c-myc / Q000235:genetics / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D056564:Sirtuin 1; D037761:Sirtuins / Q000235:genetics / Q000378:metabolism*; D019098:Telomerase / Q000235:genetics / Q000378:metabolism; D014162:Transfection
C489427:MYC protein, human; D016271:Proto-Oncogene Proteins c-myc; D034741:RNA, Small Interfering; C509186:TERT protein, human; D019098:Telomerase; C447939:SIRT1 protein, human; D056564:Sirtuin 1; D037761:Sirtuins