title: Gnot1, a member of a new homeobox gene subfamily, is expressed in a dynamic, region-specific domain along the proximodistal axis of the developing limb.
abstract: Limb development endures as an excellent model for pattern formation in vertebrates. We have identified Gnot1 as a member of a new homeobox gene subfamily. Gnot1 is expressed in a dynamic temporospatial distribution in the developing limb, initially correlating with regions destined to form distal structures and then becoming progressively more restricted to specific regions determined to give rise to wrist and ankle. Micro-surgical alteration of the developmental program of the limb reveals that Gnot1 is expressed in a position- and fate-dependent manner, responding both to signals from the apical ridge and the polarizing zone. Furthermore, Gnot1 activation by polarizing signals occurs temporally downstream of Hoxd gene activation, but well before the first appearance of condensations that will give rise to the carpus of the wrist. The features of Gnot1 expression suggest a role for this gene in regulating pattern formation during limb development.
authors.affiliation: Laboratory of Pathology, NCI, NICHD, NIH, Bethesda, MD 20892, USA.
authors.forename: M
authors.initials: M
authors.lastname: Ranson
authors.forename: C
authors.initials: C
authors.lastname: Tickle
authors.forename: K A
authors.initials: KA
authors.lastname: Mahon
authors.forename: S
authors.initials: S
authors.lastname: Mackem
mesh_terms: D000367:Age Factors; D000595:Amino Acid Sequence; D000818:Animals; D030161:Avian Proteins; D001483:Base Sequence; D002642:Chick Embryo; D003001:Cloning, Molecular; D018076:DNA, Complementary; D005121:Extremities / Q000196:embryology* / Q000502:physiology; D018507:Gene Expression Regulation, Developmental; D005801:Genes, Homeobox; D018398:Homeodomain Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D009024:Morphogenesis; D005810:Multigene Family; D016372:RNA, Antisense / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D015533:Transcriptional Activation; D014921:Wings, Animal / Q000196:embryology / Q000378:metabolism / Q000601:surgery
chemical_list: D030161:Avian Proteins; D018076:DNA, Complementary; C095588:Gnot1 protein, chicken; D018398:Homeodomain Proteins; D016372:RNA, Antisense