Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
2004-2-9
pubmed:abstractText
Bioinformatic and molecular cloning tools were used to identify and isolate cDNA clones from mouse and human tissues that encode the sixth member of the K(+)-dependent Na+/Ca2+ exchanger family, NCKX6. The mouse NCKX6 protein is 585 amino acids long and shares about 62% sequence similarity with previously identified exchangers in the alpha-repeat regions but has little primary sequence similarity outside these regions. NCKX6 transcripts of 4 kb are abundantly expressed in all tissues examined and are thus more broadly distributed than previously described NC(K)X family members. Two alternatively spliced products of this novel gene were identified that encode proteins of different length. The short isoform differs from the full-length isoform at the C-terminal hydrophobic domain as a result of a shift in the reading frame caused by the deletion of two exons. Both NCKX6 isoforms were expressed in HEK-293 cells. Functional analysis by digital imaging of fura-2 loaded transfected HEK-293 cells demonstrated that the short isoform exhibited K(+)-dependent Na+/Ca2+ exchange activity whereas the full-length isoform did not. The latter was retained within the endoplasmic reticulum, whereas the short isoform was present at the plasma membrane in transfected cells. Immunofluorescence studies examining NCKX6 expression in native tissue using an NCKX6-specific antibody showed intense labeling of the cardiac sarcolemmal membrane. The discovery of NCKX6 therefore reveals a novel member of the Na+/Ca2+ exchanger superfamily whose ubiquitous expression in all tissues suggests an important role for K(+)-dependent Na+/Ca2+ exchange in maintaining cellular Ca2+ homeostasis in diverse tissues and cell types.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
13
pubmed:volume
279
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5867-76
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:14625281-Alternative Splicing, pubmed-meshheading:14625281-Amino Acid Sequence, pubmed-meshheading:14625281-Animals, pubmed-meshheading:14625281-Blotting, Northern, pubmed-meshheading:14625281-Calcium, pubmed-meshheading:14625281-Cell Line, pubmed-meshheading:14625281-Cell Membrane, pubmed-meshheading:14625281-Cloning, Molecular, pubmed-meshheading:14625281-Computational Biology, pubmed-meshheading:14625281-DNA, Complementary, pubmed-meshheading:14625281-Fluorescent Antibody Technique, Indirect, pubmed-meshheading:14625281-Humans, pubmed-meshheading:14625281-Mice, pubmed-meshheading:14625281-Microscopy, Fluorescence, pubmed-meshheading:14625281-Models, Biological, pubmed-meshheading:14625281-Molecular Sequence Data, pubmed-meshheading:14625281-Myocardium, pubmed-meshheading:14625281-Potassium, pubmed-meshheading:14625281-Protein Isoforms, pubmed-meshheading:14625281-Protein Structure, Tertiary, pubmed-meshheading:14625281-RNA, Messenger, pubmed-meshheading:14625281-Rats, pubmed-meshheading:14625281-Sarcolemma, pubmed-meshheading:14625281-Sequence Homology, Amino Acid, pubmed-meshheading:14625281-Sodium-Calcium Exchanger, pubmed-meshheading:14625281-Time Factors, pubmed-meshheading:14625281-Tissue Distribution, pubmed-meshheading:14625281-Transfection
pubmed:year
2004
pubmed:articleTitle
Molecular cloning of a sixth member of the K+-dependent Na+/Ca2+ exchanger gene family, NCKX6.
pubmed:affiliation
Cardiovascular Research Group, Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, Alberta T2N 4N1, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't