Solute carrier family 4 member 1 adaptor protein (SLC4A1AP)

Solute carrier family 4 member 1 adaptor protein (SLC4A1AP), also known as kanadaptin or HLC3, is a widely expressed nuclear protein with currently unknown precise function in humans. Structurally, it contains a forkhead-associated (FHA) domain—which binds phosphopeptides and commonly mediates phosphorylation-dependent interactions within cellular signaling pathways—and a double-stranded RNA binding domain (dsRBD), suggesting a potential role in nucleic acid binding and regulation. It localizes to the nucleus and mitochondria, and is part of a proteome core broadly present in human tissues. The protein was initially described as an adaptor for the kidney anion exchanger (kAE1), with a hypothesized role in membrane trafficking, but subsequent studies found no strong interaction with kAE1 in human systems. Consequently, its precise biological function and physiological binding partners remain unclear, though its domain structure implicates it in signaling pathways, potentially as a phospho-dependent scaffold that regulates assembly of protein complexes, possibly influencing transcription, DNA-damage response, or cell cycle control. Some gene aliases and early literature link it to cancer, especially via the alternate name “human lung cancer oncogene 3 protein,” but there is no strong, direct evidence for SLC4A1AP as an oncogene or direct clinical biomarker to date. No drugs or therapeutics are currently known to directly interact with SLC4A1AP, nor is it an established therapeutic target.

Other names

KanadaptinHLC3HLC-3Human lung cancer oncogene 3 proteinKidney anion exchanger adapter proteinLung cancer oncogene 3Solute carrier family 4 (anion exchanger), member 1, adapter proteinSlc4a1ap (gene symbol in other species)