Linked Life Data

19726549

Source:http://linkedlifedata.com/resource/pubmed/id/19726549

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2009-11-2
pubmed:abstractText
Kidney organogenesis depends on reciprocal interactions between the ureteric bud (UB) and the metanephric mesenchyme (MM) to form the UB-derived collecting system and MM-derived nephron. With the advent of in vitro systems, it is clear that UB branching can occur independently of MM contact; however, little has been done to detail the role of MM cellular contact in this process. Here, a model system in which the cultured isolated UB is recombined with uninduced MM is used to isolate the effects of the MM progenitor tissue on the development and maturation of the collecting system. By morphometrics, we demonstrate that cellular contact with the MM is required for vectorial elongation of stalks and tapering of luminal caliber of UB-derived tubules. Expression analysis of developmentally significant genes indicates the cocultured tissue is most similar to an embryonic day 19 (E19) kidney. The likely major contributor to this is the functional maturation of the collecting duct and proximal nephron segments in the UB-induced MM, as measured by quantitative PCR, of the collecting duct-specific arginine vasopressin receptor and the nephron tubule segment-specific organic anion transporter OAT1, Na-P(i) type 2 cotransporter, and Tamm-Horsfall protein gene expressions. However, expression of aquaporin-2 is upregulated similarly in isolated UB and cocultured tissue, suggesting that some aspects of functional maturation can occur independently of MM cellular contact. In addition to its sculpting effects, the MM normalized a "branchless" UB morphology induced by FGF7 or heregulin in isolated UB culture. The morphological changes induced by the MM were accompanied by a reassignment of GFRalpha1 (a receptor for GDNF) to tips. Such "quality control" by the MM of UB morphology may provide resiliency to the branching program. This may help to explain a number of knockout phenotypes in which branching and/or cystic defects are less impressive than expected. A second hit in the MM may thus be necessary to make these defects fully apparent.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1522-1466
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
297
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
F1330-41
pubmed:dateRevised
2011-4-28
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
The instructive role of metanephric mesenchyme in ureteric bud patterning, sculpting, and maturation and its potential ability to buffer ureteric bud branching defects.
pubmed:affiliation
Department of Medicine, University of California, San Diego, California 92093-0693, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural