TBC1 domain family member 5 (TBC1D5)

TBC1 domain family member 5 (TBC1D5) is an enzyme belonging to the TBC (Tre-2/Bub2/Cdc16) domain-containing protein family, functioning as a GTPase-activating protein (GAP) for Rab7, an essential regulator of intracellular membrane trafficking. TBC1D5 acts as a key accessory and regulatory protein for the retromer complex, where it negatively regulates retromer function by promoting Rab7 GTP hydrolysis and thus controlling the dissociation of membrane-associated retromer. Loss or knockdown of TBC1D5 leads to enhanced activation of Rab7 and promotes retromer-mediated trafficking of proteins from endosomes to the Golgi and plasma membrane. TBC1D5 interacts tightly and specifically with the core subunits of the retromer complex (mainly VPS29 and VPS35), and this interaction plays a fundamental role in endosome dynamics, protein sorting, and cellular homeostasis. Dysregulation of TBC1D5, retromer function, or associated sorting mechanisms is implicated in diseases such as neurodegeneration, notably Alzheimer’s disease, due to impacts on trafficking and amyloid precursor protein processing[1][2][3]. There are no currently known drugs targeting TBC1D5 directly, and it is not yet a druggable target, but it is an active subject of basic research for understanding trafficking diseases and therapeutic strategies.

Other names

KIAA0210TBC1D5