BRCA1 negatively regulates ITPK1

Neural tube defects (NTDs) are common, severe congenital malformations. Gene BRCA1 encodes a nuclear phosphoprotein that has a role in maintaining genomic stability, and it also acts as a tumor suppressor. Inositol 1,3,4-trisphosphate 5/6-kinase (ITPK1) is a key regulatory enzyme at the branch point for the synthesis of inositol hexakisphosphate (IP6), an intracellular signaling molecule. Both genes are involved in neural tube defects, but the relationship between the two genes is unclear. In this paper, by the virtue of bioinformatics analysis, it is revealed that BRCA1 negatively regulates ITPK1. In human brain, BRCA1 has a low expression level, while ITPK1 has a high one, showing a reverse pattern against BRCA1. It is inferred that BRCA1 binds to promoter of ITPK1, playing a role of inhibiting transcription of ITPK1. One of binding site of BRCA1 on promoter of ITPK1 is at 93403144 of human chromosome 14. The site is also a single nucleotide polymorphism (SNP) site, suggesting variation of the SNP site will affect the binding of BRCA1, thus, it associates with NTD.