GHITM (growth hormone inducible transmembrane protein) is a mitochondrial transmembrane protein that plays critical roles in maintaining mitochondrial structure and function. The protein localizes to the inner mitochondrial membrane where it regulates calcium and proton transport, functioning as both a proton-dependent calcium efflux mediator and an electroneutral mitochondrial proton/potassium exchanger 1. GHITM is essential for maintaining mitochondrial tubular network integrity and cristae organization, with knockout cells displaying fragmented mitochondria, vacuolar cristae structure, reduced membrane potential, and impaired respiration 1. The protein belongs to the Bax inhibitory protein-like (TMBIM) family and affects apoptotic susceptibility, with GHITM-deficient cells showing increased sensitivity to apoptotic stimuli 1. GHITM demonstrates ubiquitous expression across mammalian tissues and cell lines, with expression patterns suggesting developmental regulation 2. In cancer contexts, GHITM appears to function as a tumor suppressor in renal cell carcinoma, where its downregulation correlates with poor prognosis and it regulates PD-L1 expression through Notch signaling pathways 3. The protein also shows promise as a stable housekeeping gene for normalization in gene expression studies, particularly in breast cancer research 4.