Linked Life Data

10617675

Source:http://linkedlifedata.com/resource/pubmed/id/10617675

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2000-1-20
pubmed:abstractText
Sister of P-glycoprotein (SPGP), a novel murine cDNA and member of the ATP-binding cassette superfamily highly homologous to P-glycoprotein (Pgp), was cloned. Moreover, its genomic clone was isolated and localized to chromosome 2 by fluorescence in situ hybridization. SPGP was functionally evaluated relative to MDR1 after subcloning SPGP cDNA into a retroviral bicistronic vector capable of expressing both SPGP and the green fluorescent protein. LLC-PK1 and MDCKII cells were transduced with this retrovirus and SPGP-positive clones were isolated. Drug uptake and efflux was compared in cells ectopically expressing either SPGP or human MDR1. SPGP cells had decreased uptake of taurocholate and vinblastine compared with LLC-PK1 cells. Additional studies revealed that vinblastine efflux was accelerated by SPGP compared with LLC-PK1. Further comparison revealed that although MDR1 easily impaired uptake of vincristine, daunomycin, paclitaxel, and digoxin, SPGP had no effect on uptake of these drugs. However, further studies demonstrated that, like MDR1, SPGP effluxed calcein-acetoxymethyl ester (AM). Unlike MDR1, SPGP was incapable of effluxing rhodamine 123. Although cyclosporine A and reserpine blocked calcein-AM transport by MDR1, these drugs had either minimal or no effect, respectively, on blocking SPGP efflux of calcein-AM. In contrast, ditekiren, a linear hexapeptide, readily and preferentially inhibited SPGP efflux of calcein-AM. Further studies with three structural analogs of ditekiren revealed that one analog inhibited SPGP efflux of calcein-AM, although not as potently as ditekiren. These are the first studies to reveal that SPGP has distinct transport properties compared with MDR1.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0026-895X
pubmed:author
pubmed:issnType
Print
pubmed:volume
57
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
24-35
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Cloning and expression of murine sister of P-glycoprotein reveals a more discriminating transporter than MDR1/P-glycoprotein.
pubmed:affiliation
Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't