Functional specificity of Hoxa-4 in vertebral patterning lies outside of the homeodomain.
The Hox family of proteins plays a central role in establishing the body plan of a wide range of metazoan organisms. Each member of this family of transcriptional regulators has a distinct functional specificity, yet they bind to similar DNA target sequences through their conserved homeodomain. The mechanisms whereby Hox proteins achieve their diverse specificities in vivo remain undefined. Using the opposing effects of Hoxa-4 and Hoxc-8 in vertebral patterning, we demonstrate by replacing the homeodomain of Hoxa-4 with that of Hoxc-8 that the functional specificity of Hoxa-4 does not track with the homeodomain. These observations provide evidence that other regions of Hox proteins play an important role in mediating functional specificity during mammalian embryogenesis.
Sreenath
T L
TL
Department of Virology, Jerome H. Holland Laboratory, Rockville, MD 20855, USA.
Pollock
R A
RA
Bieberich
C J
CJ
D000818:Animals; D000831:Animals, Newborn; D001483:Base Sequence; D003598:Cytoskeletal Proteins; D018507:Gene Expression Regulation, Developmental; D005801:Genes, Homeobox; D018398:Homeodomain Proteins / Q000378:metabolism*; D008969:Molecular Sequence Data; D010641:Phenotype; D011506:Proteins / Q000378:metabolism; D013379:Substrate Specificity; D019076:Transgenes
D003598:Cytoskeletal Proteins; D018398:Homeodomain Proteins; C097906:LLGL1 protein, human; D011506:Proteins