Linked Life Data

9334276

Source:http://linkedlifedata.com/resource/pubmed/id/9334276

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
21
pubmed:dateCreated
1997-12-17
pubmed:abstractText
The maternal dorsal determinants required for the specification of the dorsal territories of Xenopus early gastrulae are located at the vegetal pole of unfertilised eggs and are moved towards the prospective dorsal region of the fertilised egg during cortical rotation. While the molecular identity of the determinants is unknown, there are dorsal factors in the vegetal cortical cytoplasm (VCC). Here, we show that the VCC factors, when injected into animal cells activate the zygotic genes Siamois and Xnr3, suggesting that they act along the Wnt/beta-catenin pathway. In addition, Siamois and Xnr3 are activated at the vegetal pole of UV-irradiated embryos, indicating that these two genes are targets of the VCC factors in all embryonic cells. However, the consequences of their activation in cells that occupy different positions along the animal-vegetal axis differ. Dorsal vegetal cells of normal embryos or VCC-treated injected animal cells are able to dorsalise ventral mesoderm in conjugate experiments but UV-treated vegetal caps do not have this property. This difference is unlikely to reflect different levels of activation of FGF or activin-like signal transduction pathways but may reflect the activation of different targets of Siamois. Chordin, a marker of the head and axial mesoderm, is activated by the VCC/Siamois pathway in animal cells but not in vegetal cells whereas cerberus, a marker of the anterior mesendoderm which lacks dorsalising activity, can only be activated by the VCC/Siamois pathway in vegetal cells. We propose that the regionalisation of the organiser during gastrulation proceeds from the differential interpretation along the animal-vegetal axis of the activation of the VCC/beta-catenin/Siamois pathway.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Cytoskeletal Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Glycoproteins, http://linkedlifedata.com/resource/pubmed/chemical/Homeodomain Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Intercellular Signaling Peptides..., http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Transforming Growth..., http://linkedlifedata.com/resource/pubmed/chemical/Trans-Activators, http://linkedlifedata.com/resource/pubmed/chemical/Transforming Growth Factor beta, http://linkedlifedata.com/resource/pubmed/chemical/Xenopus Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Xnr3 protein, Xenopus, http://linkedlifedata.com/resource/pubmed/chemical/beta Catenin, http://linkedlifedata.com/resource/pubmed/chemical/beta-catenin protein, Xenopus, http://linkedlifedata.com/resource/pubmed/chemical/chordin, http://linkedlifedata.com/resource/pubmed/chemical/siamois protein, Xenopus
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0950-1991
pubmed:author
pubmed:issnType
Print
pubmed:volume
124
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4275-86
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Animal and vegetal pole cells of early Xenopus embryos respond differently to maternal dorsal determinants: implications for the patterning of the organiser.
pubmed:affiliation
Institut de Biologie du Développement de Marseille, UMR 6545 CNRS-Université de la Méditerranée, Campus de Luminy, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't