Linked Life Data

15308648

Source:http://linkedlifedata.com/resource/pubmed/id/15308648

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
43
pubmed:dateCreated
2004-10-18
pubmed:abstractText
Salvage pathways play an important role in providing nucleobases to cells, which are unable to synthesize sufficient amounts for their needs. Cellular uptake systems for pyrimidines have been described, but in higher eukaryotes, transporters for thymine and uracil have not been identified. Two plant transporters, AtUPS1 and PvUPS1, were recently identified as transporters for allantoin in Arabidopsis and French bean, respectively. However, Arabidopsis, in contrast to tropical legumes, uses mainly amino acids for long distance transport. Allantoin transport has not been described in the Brassicaceae. Thus, the physiological substrates of ureide permease (UPS) transporters in Arabidopsis may be compounds structurally related to allantoin. A detailed analysis of the substrate specificities of two members of the AtUPS family shows that AtUPS1 and AtUPS2 mediate high affinity uracil and 5-fluorouracil (a toxic uracil analogue) transport when expressed in yeast and Xenopus oocytes. Consistent with a function during germination and early seedling development, AtUPS1 expression is transiently induced during the early stages of seedling development followed by up-regulation of AtUPS2 expression. Arabidopsis ups2 insertion mutants and ups1 lines, in which transcript levels were reduced by post-transcriptional gene silencing, are more tolerant to 5-fluorouracil as compared with wild type plants. The results suggest that in Arabidopsis UPS transporters are the main transporters for uracil and potentially other nucleobases, whereas during evolution legumes may have taken advantage of the low selectivity of UPS proteins for long distance transport of allantoin.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
22
pubmed:volume
279
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
44817-24
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:15308648-Allantoin, pubmed-meshheading:15308648-Animals, pubmed-meshheading:15308648-Arabidopsis, pubmed-meshheading:15308648-Arabidopsis Proteins, pubmed-meshheading:15308648-Biological Transport, pubmed-meshheading:15308648-DNA, pubmed-meshheading:15308648-Dose-Response Relationship, Drug, pubmed-meshheading:15308648-Electrophysiology, pubmed-meshheading:15308648-Escherichia coli, pubmed-meshheading:15308648-Fluorouracil, pubmed-meshheading:15308648-Gene Silencing, pubmed-meshheading:15308648-Membrane Transport Proteins, pubmed-meshheading:15308648-Models, Genetic, pubmed-meshheading:15308648-Mutation, pubmed-meshheading:15308648-Oocytes, pubmed-meshheading:15308648-Phenotype, pubmed-meshheading:15308648-Promoter Regions, Genetic, pubmed-meshheading:15308648-RNA, pubmed-meshheading:15308648-RNA, Messenger, pubmed-meshheading:15308648-RNA Processing, Post-Transcriptional, pubmed-meshheading:15308648-Substrate Specificity, pubmed-meshheading:15308648-Up-Regulation, pubmed-meshheading:15308648-Uracil, pubmed-meshheading:15308648-Xenopus, pubmed-meshheading:15308648-Xenopus laevis
pubmed:year
2004
pubmed:articleTitle
UPS1 and UPS2 from Arabidopsis mediate high affinity transport of uracil and 5-fluorouracil.
pubmed:affiliation
Plant Physiology, ZMBP, Auf der Morgenstelle 1, D-72076 Tübingen, Germany.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't