fragile histidine triad
The information on this page was automatically extracted from online scientific databases.
From NCBI Gene:
This gene, a member of the histidine triad gene family, encodes a diadenosine 5',5'''-P1,P3-triphosphate hydrolase involved in purine metabolism. The gene encompasses the common fragile site FRA3B on chromosome 3, where carcinogen-induced damage can lead to translocations and aberrant transcripts of this gene. In fact, aberrant transcripts from this gene have been found in about half of all esophageal, stomach, and colon carcinomas. Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Oct 2009]
Cleaves P(1)-P(3)-bis(5'-adenosyl) triphosphate (Ap3A) to yield AMP and ADP. Can also hydrolyze P(1)-P(4)-bis(5'-adenosyl) tetraphosphate (Ap4A), but has extremely low activity with ATP. Modulates transcriptional activation by CTNNB1 and thereby contributes to regulate the expression of genes essential for cell proliferation and survival, such as CCND1 and BIRC5. Plays a role in the induction of apoptosis via SRC and AKT1 signaling pathways. Inhibits MDM2-mediated proteasomal degradation of p53/TP53 and thereby plays a role in p53/TP53-mediated apoptosis. Induction of apoptosis depends on the ability of FHIT to bind P(1)-P(3)-bis(5'-adenosyl) triphosphate or related compounds, but does not require its catalytic activity, it may in part come from the mitochondrial form, which sensitizes the low-affinity Ca(2+) transporters, enhancing mitochondrial calcium uptake. Functions as tumor suppressor.
Associated with digestive tract cancers. Numerous tumor types are found to have aberrant forms of FHIT protein due to deletions in a coding region of chromosome 3p14.2 including the fragile site locus FRA3B.
A chromosomal aberration involving FHIT has been found in a lymphoblastoid cell line established from a family with renal cell carcinoma and thyroid carcinoma. Translocation t(3;8)(p14.2;q24.1) with RNF139. Although the 3p14.2 breakpoint has been shown to interrupt FHIT in its 5-prime non-coding region, it is unlikely that FHIT is causally related to renal or other malignancies.