Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
2004-10-7
pubmed:abstractText
Expression of a Hoxa-7/lacZ reporter construct in transgenic mouse embryos is shifted anteriorly when the upstream enhancer is multimerized. The shift occurs in spinal ganglia, neurectoderm and in both paraxial and lateral plate mesoderms. Much of the multimer effect is inhibited by destruction of a single caudal (cdx) binding motif in the additional copies of the enhancer. These observations are in agreement with earlier enhancer multimerization analyses made for Hoxb-8 (Charite et al., 1998). Our findings therefore provide further evidence that the anterior limit of a Hox gene's expression domain is normally dependent upon and is determined by, the dosage of transcription factor(s) which bind to its enhancer element(s) and that these factors may be, or must include, the cdx proteins. We consider these findings in terms of both instructional (morphogen-like) gradient and timing models for the establishment of Hox gene expression domains. Enhancer multimerization results in an earlier onset of Hoxa-7/lacZ activity in the embryo. In neurectoderm at 8.7 days and in mesoderm at 10.5 days, the anterior boundaries of expression are located posterior to those seen at some earlier stages of development. We discuss how these findings are in keeping with a model where Hox expression boundaries become set along instructional cdx gradients, formed by cdx decay in cells moving away from the primitive streak region.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0214-6282
pubmed:author
pubmed:issnType
Print
pubmed:volume
48
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
613-22
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:15470633-Amino Acid Motifs, pubmed-meshheading:15470633-Animals, pubmed-meshheading:15470633-Base Sequence, pubmed-meshheading:15470633-Binding Sites, pubmed-meshheading:15470633-Chick Embryo, pubmed-meshheading:15470633-Ectoderm, pubmed-meshheading:15470633-Enhancer Elements, Genetic, pubmed-meshheading:15470633-Gastrula, pubmed-meshheading:15470633-Genes, Reporter, pubmed-meshheading:15470633-Homeodomain Proteins, pubmed-meshheading:15470633-Lac Operon, pubmed-meshheading:15470633-Mesoderm, pubmed-meshheading:15470633-Mice, pubmed-meshheading:15470633-Models, Genetic, pubmed-meshheading:15470633-Molecular Sequence Data, pubmed-meshheading:15470633-Neoplasm Proteins, pubmed-meshheading:15470633-Plasmids, pubmed-meshheading:15470633-Protein Structure, Tertiary, pubmed-meshheading:15470633-Time Factors, pubmed-meshheading:15470633-Transgenes
pubmed:year
2004
pubmed:articleTitle
Additional enhancer copies, with intact cdx binding sites, anteriorize Hoxa-7/lacZ expression in mouse embryos: evidence in keeping with an instructional cdx gradient.
pubmed:affiliation
Department of Development and Genetics, The Babraham Institute, Babraham, Cambridge, UK. stephen.gaunt@bbsrc.ac.uk.
pubmed:publicationType
Journal Article