Hint1

Hint1 (histidine triad nucleotide binding protein 1), also known as PRKCNH1 or PKCI1, is a 126 amino acid protein that localizes to both the cytoplasm and the nucleus and contains one HIT (histidine triad) domain. Widely expressed and existing as a homodimer, Hint1 functions to hydrolyze adenosine 5'-monophosphoramidate substrates, such as AMP-N-alanine methyl ester, AMP-morpholidate and AMP-α-acetyl lysine methyl ester, and may also inhibit PKC function and influence apoptosis. Knockdown of Hint1 mRNA results in downregulation of p53 and Bax, suggesting that Hint1 is a haploinsufficient tumor suppressor. Also, it is suspected that promoter hypermethylation of the gene encoding Hint1 may play a role in hepatocarcinogenesis.