Linked Life Data

11827541

Source:http://linkedlifedata.com/resource/pubmed/id/11827541

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2002-2-5
pubmed:abstractText
Members of the ecto-nucleoside triphosphate diphosphohydrolase (eNTPDase) family exhibit distinctive substrate specificities, but how such specificities are achieved by enzymes with identical putative catalytic domains is unknown. Previously we showed that H59G substitution changes CD39 from an apyrase to an adenosine diphosphatase (ADPase) in a manner that depends on intact associations of both transmembrane domains with the membrane. Here we show that the extracellular domain of CD39L1 ecto-adenosine triphosphatase (ecto-ATPase) has the same 3:1 ATP:ADP hydrolysis ratio as the extracellular domain of CD39, suggesting that the transmembrane domains are required to confer the native substrate specificities on each enzyme. As in CD39, H50G substitution has little effect on the activity of the CD39L1 extracellular domain or solubilized monomers. However, H50G substitution diminishes both ATPase and ADPase activities of native CD39L1, in contrast to its selective effect on ATPase activity in CD39, suggesting that the transmembrane domains confer different ADP hydrolysis mechanisms on CD39 and CD39L1. We then show that the transmembrane domains of CD39L1 can substitute for those of CD39 in conferring native CD39 substrate specificity and regulation of H59 but that the transmembrane domains of CD39 confer neither CD39 nor CD39L1 properties on the CD39L1 extracellular domain. These results suggest that non-apyrase conserved region residues in the extracellular domain contain the information specifying CD39 native properties but have a nonspecific requirement for two transmembrane domains to manifest the information.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
12
pubmed:volume
41
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1947-56
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Transmembrane domains confer different substrate specificities and adenosine diphosphate hydrolysis mechanisms on CD39, CD39L1, and chimeras.
pubmed:affiliation
Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138.
pubmed:publicationType
Journal Article, In Vitro