Hoxd4 and Rarg interact synergistically in the specification of the cervical vertebrae.
We show that, relative to single null mutants, mice bearing mutations in both Hoxd4 and Rarg display malformations of the basioccipital bone, and first (C1) and second cervical vertebrae (C2) at increased penetrance and expressivity, demonstrating synergy between Hoxd4 and Rarg in the specification of the cervical skeleton. In contrast to Rarg mutants, retinoic acid (RA) treatment on embryonic day 10.5 of Hoxd4 single or Hoxd4;Rarg double mutants does not rescue normal development of C2. Somitic expression of Hoxd4 is not altered in wild-type or Rarg mutant animals before or after RA treatment on day 10.5, suggesting that Hoxd4 and Rarg act in parallel to regulate the expression of target genes directing skeletogenesis.
Folberg
A
A
McGill Cancer Centre, McGill University, Montreal, Quebec, Canada.
Kovács
E N
EN
Huang
H
H
Houle
M
M
Lohnes
D
D
Featherstone
M S
MS
D000818:Animals; D002574:Cervical Vertebrae / Q000002:abnormalities / Q000187:drug effects / Q000196:embryology*; D005260:Female; D018507:Gene Expression Regulation, Developmental; D018398:Homeodomain Proteins / Q000235:genetics* / Q000378:metabolism; D008297:Male; D051379:Mice; D008817:Mice, Mutant Strains; D018168:Receptors, Retinoic Acid / Q000235:genetics* / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics; D014212:Tretinoin / Q000494:pharmacology
D018398:Homeodomain Proteins; C513262:Hoxb4 protein, mouse; D018168:Receptors, Retinoic Acid; D014157:Transcription Factors; D014212:Tretinoin