Linked Life Data

15489237

Source:http://linkedlifedata.com/resource/pubmed/id/15489237

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
52
pubmed:dateCreated
2004-12-21
pubmed:abstractText
The epithelial Ca(2+) channels TRPV5 and TRPV6 mediate the Ca(2+) influx in 1,25-dihydroxyvitamin D(3)-responsive epithelia and are therefore essential in the maintenance of the body Ca(2+) balance. These Ca(2+) channels assemble in (hetero)tetrameric channel complexes with different functional characteristics regarding Ca(2+)-dependent inactivation, ion selectivity, and pharmacological block. Glutathione S-transferase pull-downs and co-immunoprecipitations demonstrated an essential role of the intracellular N- and C-tails in TRPV5 channel assembly by physical interactions between N-N tails, C-C tails, and N-C-tails. Patch clamp analysis in human embryonic kidney (HEK293) cells and (45)Ca(2+) uptake experiments in Xenopus laevis oocytes co-expressing TRPV5 wild-type and truncated proteins indicated that TRPV5 Delta N (deleted N-tail) and TRPV5 Delta C (deleted C-tail) decreased channel activity of wild-type TRPV5 in a dominant-negative manner, whereas TRPV5 Delta N Delta C (deleted N-tail/C-tail) did not affect TRPV5 activity. Oocytes co-expressing wild-type TRPV5 and TRPV5 Delta N or TRPV5 Delta C showed virtually no wild-type TRPV5 expression on the plasma membrane, whereas co-expression of wild-type TRPV5 and TRPV5 Delta N Delta C displayed normal channel surface expression. This indicates that TRPV5 trafficking toward the plasma membrane was disturbed by assembly with TRPV5 Delta N or TRPV5 Delta C but not with TRPV5 Delta N Delta C. TRPV5 channel assembly signals were refined between amino acid positions 64-77 and 596-601 in the N-tail and C-tail, respectively. Pull-down assays and co-immunoprecipitations demonstrated that N- or C-tail mutants lacking these critical assembly domains were unable to interact with tails of TRPV5. In conclusion, two domains in the N-tail (residues 64-77) and C-tail (residues 596-601) of TRPV5 are important for channel subunit assembly, subsequent trafficking of the TRPV5 channel complex to the plasma membrane, and channel activity.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
24
pubmed:volume
279
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
54304-11
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed-meshheading:15489237-Amino Acid Sequence, pubmed-meshheading:15489237-Animals, pubmed-meshheading:15489237-Calcium, pubmed-meshheading:15489237-Calcium Channels, pubmed-meshheading:15489237-Cell Line, pubmed-meshheading:15489237-Cell Membrane, pubmed-meshheading:15489237-Electrophysiology, pubmed-meshheading:15489237-Embryo, Mammalian, pubmed-meshheading:15489237-Embryo, Nonmammalian, pubmed-meshheading:15489237-Escherichia coli, pubmed-meshheading:15489237-Gene Expression, pubmed-meshheading:15489237-Glutathione Transferase, pubmed-meshheading:15489237-Humans, pubmed-meshheading:15489237-Immunosorbent Techniques, pubmed-meshheading:15489237-Kidney, pubmed-meshheading:15489237-Oocytes, pubmed-meshheading:15489237-Patch-Clamp Techniques, pubmed-meshheading:15489237-Peptide Fragments, pubmed-meshheading:15489237-RNA, Complementary, pubmed-meshheading:15489237-Recombinant Fusion Proteins, pubmed-meshheading:15489237-Sequence Alignment, pubmed-meshheading:15489237-Structure-Activity Relationship, pubmed-meshheading:15489237-TRPV Cation Channels, pubmed-meshheading:15489237-Transfection, pubmed-meshheading:15489237-Xenopus laevis
pubmed:year
2004
pubmed:articleTitle
Molecular determinants in TRPV5 channel assembly.
pubmed:affiliation
Department of Physiology, Nijmegen Center for Molecular Life Sciences, Radboud University Nijmegen Medical Center, NL-6500 HB Nijmegen, The Netherlands.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't