Structure and sequence of the human homeobox gene HOX7.
A cosmid containing the human sequence HOX7, homologous to the murine Hox-7 gene, was isolated from a genomic library, and the positions of the coding sequences were determined by hybridization. DNA sequence analysis demonstrated two exons that code for a homeodomain-containing protein of 297 amino acids. The open reading frame is interrupted by a single intron of approximately 1.6 kb, the splice donor and acceptor sites of which conform to known consensus sequences. The human HOX7 coding sequence has a very high degree of identity with the murine Hox-7 cDNA. Within the homeobox, the two sequences share 94% identity at the DNA level, all substitutions being silent. This high level of sequence similarity is not confined to the homeodomain; overall the human and murine HOX7 gene products show 80% identity at the amino acid level. Both the 5' and 3' untranslated regions also show significant similarity to the murine gene, with 79 and 70% sequence identity, respectively. The sequence upstream of the coding sequence of exon 1 contains a GC-rich putative promoter region. There is no TATA box, but a CCAAT and numerous GC boxes are present. The region encompassing the promoter region, exon 1, and the 5' region of exon 2 have a higher than expected frequency of CpG dinucleotides; numerous sites for rare-cutter restriction enzymes are present, a characteristic of HTF islands.
Department of Biochemistry and Molecular Genetics, St. Mary's Hospital Medical School, Imperial College of Science, Technology, and Medicine, London, United Kingdom.
J E
JE
Hewitt
L N
LN
Clark
A
A
Ivens
R
R
Williamson
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D016384:Consensus Sequence; D003360:Cosmids / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics*; D005091:Exons / Q000235:genetics; D005801:Genes, Homeobox / Q000235:genetics*; D018398:Homeodomain Proteins; D006801:Humans; D007438:Introns / Q000235:genetics; D051957:MSX1 Transcription Factor; D051379:Mice; D008969:Molecular Sequence Data; D005810:Multigene Family / Q000235:genetics*; D016366:Open Reading Frames / Q000235:genetics; D012091:Repetitive Sequences, Nucleic Acid; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid
D004268:DNA-Binding Proteins; D018398:Homeodomain Proteins; D051957:MSX1 Transcription Factor; C484083:MSX1 protein, human