title: Homez, a homeobox leucine zipper gene specific to the vertebrate lineage.
abstract: This work describes a vertebrate homeobox gene, designated Homez (homeodomain leucine zipper-encoding gene), that encodes a protein with an unusual structural organization. There are several regions within Homez, including three atypical homeodomains, two leucine zipper-like motifs, and an acidic domain. The gene is ubiquitously expressed in human and murine tissues, although the expression pattern is more restricted during mouse development. Genomic analysis revealed that human and mouse genes are located at 14q11.2 and 14C, respectively, and are composed of two exons. The zebrafish and pufferfish homologs share high similarity to mammalian sequences, particularly within the homeodomain sequences. Based on homology of homeodomains and on the similarity in overall protein structure, we delineate Homez and members of ZHX family of zinc finger homeodomain factors as a subset within the superfamily of homeobox-containing proteins. The type and composition of homeodomains in the Homez subfamily are vertebrate-specific. Phylogenetic analysis indicates that Homez lineage was separated from related genes >400 million years ago before separation of ray- and lobe-finned fishes. We apply a duplication-degeneration-complementation model to explain how this family of genes has evolved.
authors.affiliation: Department of Molecular, Cellular, and Developmental Biology, Yale University, 266 Whitney Avenue, New Haven, CT 06520, USA. bayarsaihan@yale.edu
authors.forename: Dashzeveg
authors.initials: D
authors.lastname: Bayarsaihan
authors.forename: Badam
authors.initials: B
authors.lastname: Enkhmandakh
authors.forename: Aleksandr
authors.initials: A
authors.lastname: Makeyev
authors.forename: John M
authors.initials: JM
authors.lastname: Greally
authors.forename: James F
authors.initials: JF
authors.lastname: Leckman
authors.forename: Frank H
authors.initials: FH
authors.lastname: Ruddle
mesh_terms: D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D004247:DNA / Q000378:metabolism; D018076:DNA, Complementary / Q000302:isolation & purification; D019281:Dimerization; D019143:Evolution, Molecular; D005801:Genes, Homeobox; D018398:Homeodomain Proteins / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D016350:Leucine Zippers; D051379:Mice; D008969:Molecular Sequence Data; D051381:Rats
chemical_list: D018076:DNA, Complementary; D018398:Homeodomain Proteins; D004247:DNA