TBC1 Domain Family, Member 7 (TBC1D7)

TBC1D7 was expressed as a 30-kD protein. Northern blot analysis detected an approximately 1.1-kb transcript with high expression in human heart and low expression in kidney, liver, and placenta. Immunofluorescence studies colocalized TBC1D7 and TSC1 to the cytoplasm when expressed in NIH3T3 cells; with subcellular fractionation, TBC1D7 localized to the cytoplasmic vesicles of the endomembrane in a complex with TSC1-TSC2.TBC1D7 interacted with the TSC1-TSC2 complex. Further studies showed that TBC1D7 interacted directly with TSC1 through the C-terminal half of the TSC1 coiled-coil domain. TBC1D7 plays a role in positive regulation of the mTOR-signaling pathway. Overexpression of TBC1D7 also increased TSC1 ubiquitination.