Identification and characterization of TRIP8 gene in silico.

TRIP1-TRIP15 genes encode thyroid hormone receptor beta (TR beta)-binding proteins. TRIP10 gene encodes FNBP1 family protein with FCH, FBH, and SH3 domains. Among 15 TRIP genes, TRIP8 gene remained uncharacterized except TRIP8 partial cDNA (L40411). Here, we determined the complete coding sequence of TRIP8 gene by using bio-informatics. Nucleotide sequence of full-length TRIP8 cDNA was determined in silico by assembling nucleotide sequences of FLJ14374 and DKFZp761F0118 cDNAs. TRIP8 protein (2540 aa) was found to consist of two bipartite nuclear localization signals (codon 352-368 and 2365-2381), TRI8H1 domain (codon 1697-1873), TRI8H2 domain (codon 2057-2351), and JMJC domain (codon 2387-2486). TRI8H1, TRI8H2 and JMJC domains were conserved among TRIP8, 5qNCA (C5orf7) and TSGA proteins. TR beta-binding domain was overlapped with N-terminal part of TRI8H2 domain, and C2HC4-type zinc finger-like motif was located within C-terminal part of TRI8H1 domain. Because JMJC domain proteins are implicated in chromatin remodeling, TRIP8 was predicted to be a transcriptional regulator associated with nuclear hormone receptors. Human TRIP8 gene, consisting of 26 exons, was about 300 kb in size. Intra-species comparative genomics revealed that TRIP8-EGR2 locus at human chromosome 10q21.3 and 5qNCA-EGR1 locus at human chromosome 5q31 are paralogous regions within human genome. Microsatellite marker D10S1225, associated with Alzheimer's disease, non-syndromic congenital retinal non-attachment (NCRNA) and non-syndromic autosomal recessive persistent hyperplastic primary vitreous (arPHPV), was located within the TRIP8-EGR2 locus. This is the first report on comprehensive characterization of the TRIP8 gene.