Tn. Dear et al., THE HOX11 GENE ENCODES A DNA-BINDING NUCLEAR TRANSCRIPTION FACTOR BELONGING TO A DISTINCT FAMILY OF HOMEOBOX GENES, Proceedings of the National Academy of Sciences of the United Statesof America, 90(10), 1993, pp. 4431-4435
A translocation involving human chromosome 10, band q24, in a subset o
f T-cell acute leukemias disrupts a region surrounding the putative on
cogene HOX11, which encodes a protein with a homeodomain. The HOX11 pr
otein binds to a specific DNA sequence, it localizes to the cell nucle
us, and it transactivates transcription of a reporter gene linked to a
cis-regulatory element, suggesting that HOX11 functions in vivo as a
positive transcription activator. PCR analysis shows that the HOX11 ho
meodomain is a member of a distinct class of homeodomains, representat
ives of which occur in murine and Drosophila genomes. These all contai
n a threonine residue in place of the more common isoleucine or valine
in helix 3 of the homeodomain. HOX11 therefore appears to belong to a
family of DNA-binding transactivators of transcription.