Fine structure of the Human translocation protein 1 (HTP1/TLOC1) gene

We characterized the genomic region corresponding to the human translocatio n protein 1 (HTP1/TLOC1) cDNA previously reported. An experiment using rapi d amplification of cDNA ends revealed that the transcription initiation sit e was at -12 bp upstream from the translation initiation codon ATG. Using d irect-sequencing PCR, we determined precise intron/exon boundaries and intr on-exon composition of the gene. The gene region spanned similar to 28 kb a nd was composed of eight exons and seven introns. The lengths of exons and introns range from 48 to >1707 bp and from 0.25 to 8.2 kb, respectively. Th e translation initiation codon and the termination codon were located in ex ons 1 and 8, respectively. The nucleotide sequences of the introns were als o determined in the region around the intron/exon boundaries for 63 to 442 bp. All of the sequences around the intron/exon boundaries were consistent with the 5' and 3' consensus sequences for splice junctions of transcribed genes. Putative lariat sequences were identified between -28 and -64 nucleo tides from the 3' splice junction for all seven introns. DNA walking experi ments revealed a promoter region of 600 bp, The promoter region did not con tain an apparent TATA box or a CAT box but did contain Evi-1, GATA, v-Myb, MZF1, and AP-1 binding sites-factors known as regulatory factors on express ion of the gene in blood cells. Therefore, this gene may be one such gene.