Auxillary subunit of N-terminal acetyltransferase complexes which display alpha (N-terminal) acetyltransferase (NAT) activity ( , ). The NAT activity may be important for vascular, hematopoietic and neuronal growth and development . Required to control retinal neovascularization in adult ocular endothelial cells . In complex with XRCC6 and XRCC5 (Ku80), up-regulates transcription from the osteocalcin promoter .
Subcellular locations: Cytoplasm, Nucleus
Mainly cytoplasmic, nuclear in some cases. Present in the free cytosolic and cytoskeleton-bound polysomes, but not in the membrane-bound polysomes.
Expressed at high levels in testis and in ocular endothelial cells. Also found in brain (corpus callosum), heart, colon, bone marrow and at lower levels in most adult tissues, including thyroid, liver, pancreas, mammary and salivary glands, lung, ovary, urogenital system and upper gastrointestinal tract. Overexpressed in gastric cancer, in papillary thyroid carcinomas and in a Burkitt lymphoma cell line (Daudi). Specifically suppressed in abnormal proliferating blood vessels in eyes of patients with proliferative diabetic retinopathy.