TSC12

TSC12, also known as hamartin, is a protein encoded by the TSC1 gene. It is a tumor suppressor protein that plays a crucial role in regulating cell growth and proliferation. TSC1 forms a heterodimer with TSC2 (tuberin), and together they function as the tuberous sclerosis complex (TSC). This complex acts as a negative regulator of the mechanistic target of rapamycin (mTOR) signaling pathway. The mTOR pathway is essential for cell growth, protein synthesis, and metabolism, and its dysregulation is implicated in various diseases, including cancer and neurodevelopmental disorders.

The TSC1-TSC2 complex inhibits the activity of Rheb, a small GTPase that is a direct activator of mTOR complex 1 (mTORC1). By inhibiting mTORC1, the TSC complex prevents excessive cell growth and division. Mutations in the TSC1 gene can lead to a loss of TSC1 protein function, resulting in the hyperactivation of the mTOR pathway. This aberrant signaling contributes to the development of hamartomas, which are benign tumor-like growths, and other symptoms associated with tuberous sclerosis complex (TSC). TSC1 is found in various tissues and plays a role in neuronal development and function, as well as the regulation of cell size.