EVX2, a human homeobox gene homologous to the even-skipped segmentation gene, is localized at the 5' end of HOX4 locus on chromosome 2.
We isolated and mapped three new human homeoboxes located on chromosome 2 upstream from the reported seven HOX4 homeobox sequences. Two of them, HOX41 and HOX4H, clearly belong to the HOX gene family, in particular to homology groups 1 and 2, and possibly represent the most 5' HOX4 homeoboxes. A third homeobox 13 kb upstream from HOX41 was identified. Sequencing data show that this is the human homolog of the murine Evx-2 homeobox. Both homeoboxes are closely related to the murine Evx-1 and to the frog Xhox-3 homeoboxes. The four genes represent vertebrate homologs of Drosophila even-skipped (eve), a segmentation gene of the pair-rule class. Human EVX2 sequences belong to an active gene because they are transcribed and properly processed in cells and tissues. We have identified for the first time a homeogene of a different class at a HOX locus. These findings are relevant to the understanding of the evolution of HOX gene clusters and their regulation.
D'Esposito
M
M
International Institute of Genetics and Biophysics, CNR, Naples, Italy.
Morelli
F
F
Acampora
D
D
Migliaccio
E
E
Simeone
A
A
Boncinelli
E
E
D000595:Amino Acid Sequence; D000818:Animals; D001426:Bacterial Proteins; D001483:Base Sequence; D002889:Chromosomes, Human, Pair 2; D003001:Cloning, Molecular; D004247:DNA; D004268:DNA-Binding Proteins / Q000235:genetics*; D004330:Drosophila / Q000235:genetics; D029721:Drosophila Proteins; D005801:Genes, Homeobox; D018398:Homeodomain Proteins; D006801:Humans; D008969:Molecular Sequence Data; D005810:Multigene Family; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid; D014157:Transcription Factors; D014407:Tumor Cells, Cultured
D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D018398:Homeodomain Proteins; D014157:Transcription Factors; C052837:eve protein, Drosophila; D004247:DNA