Rhox homeobox gene cluster: recent duplication of three family members.
We recently reported the discovery of a homeobox gene cluster on the mouse X chromosome, Rhox, whose 12 members are selectively expressed in specific cell types in reproductive organs. Here we report the existence of 20 additional Rhox homeobox genes in this gene cluster. Most of the newly identified Rhox paralogs retain the same order and relative orientation as three of the originally described Rhox genes, suggesting that they arose from recent duplications of this trimer unit. Many of these new Rhox family members are expressed in the testis and placenta. Analysis of synonymous and nonsynonymous substitutions in their homeodomain region suggests that these new Rhox paralogs duplicated so recently that their encoded proteins have not yet acquired distinct DNA-binding specificities. The existence of these new Rhox genes provides an opportunity to examine the initial stages of gene cluster evolution.
James A
JA
MacLean
Diego
D
Lorenzetti
Zhiying
Z
Hu
Will J
WJ
Salerno
Jonathan
J
Miller
Miles F
MF
Wilkinson
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015139:Blotting, Southern; D018628:Gene Dosage; D020440:Gene Duplication; D005801:Genes, Homeobox; D018398:Homeodomain Proteins / Q000235:genetics* / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D005810:Multigene Family; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D014960:X Chromosome / Q000235:genetics*
D018398:Homeodomain Proteins