Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2000-1-11
pubmed:abstractText
Excess retinoids as well as retinoid deprivation cause abnormal development, suggesting that retinoid homeostasis is critical for proper morphogenesis. RALDH-2 and CYP26, two key enzymes that carry out retinoic acid (RA) synthesis and degradation, respectively, were cloned from the chick and show significant homology with their orthologs in other vertebrates. Expression patterns of RALDH-2 and CYP26 genes were determined in the early chick embryo by in situ hybridization. During gastrulation and neurulation RALDH-2 and CYP26 were expressed in nonoverlapping regions, with RALDH-2 transcripts localized to the presumptive presomitic and lateral plate mesoderm and CYP26 mRNA to the presumptive mid- and forebrain. The two domains of expression were separated by an approximately 300-micrometer-wide gap, encompassing the presumptive hindbrain. In the limb region, a similar spatial segregation of RALDH-2 and CYP26 expression was found at stages 14 and 15. Limb region mesoderm expressed RALDH-2, whereas the overlying limb ectoderm expressed CYP26. RA-synthesizing and -degrading enzymatic activities were measured biochemically in regions expressing RALDH-2 or CYP26. Regions expressing RALDH-2 generated RA efficiently from precursor retinal but degraded RA only inefficiently. Conversely, tissue expressing CYP26 efficiently degraded but did not synthesize RA. Localized regions of RA synthesis and degradation mediated by these two enzymes may therefore provide a mechanism to regulate RA homeostasis spatially in vertebrate embryos.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0012-1606
pubmed:author
pubmed:copyrightInfo
Copyright 1999 Academic Press.
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
216
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
282-96
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Complementary domains of retinoic acid production and degradation in the early chick embryo.
pubmed:affiliation
Department of Biochemistry, Baylor College of Medicine, Houston, Texas, 77030, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't