Linked Life Data

19508229

Source:http://linkedlifedata.com/resource/pubmed/id/19508229

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
2009-10-5
pubmed:abstractText
Single site-directed mutations at each of the four EF-hand loops of potassium channel-interacting protein 2.2 (KChIP2.2) were carried out to explore the functional roles of EF-hands in KChIP2.2. In contrast to those on EF-hands 1 and 2, mutations on EF-hands 3 or 4 distorted the high affinity Ca(2+)-binding site of KChIP2.2. However, the Mg(2+)-binding ability of KChIP2.2 was marginally affected by the mutations. The gross conformation of mutated KChIP2.2 was indistinguishable from wild-type KChIP2.2 as revealed by CD spectra. The results of size exclusion chromatography showed that, with exception of EF-hand 4 mutant, mutations on EF-hands 1, 2 or 3 caused KChIP2.2 to form oligomer. Pull-down assay revealed that, unlike wild-type KChIP2.2, the interaction between mutated KChIP2.2 and Kv4.2 was not notably enhanced by Ca(2+) and Mg(2+). Coexpression of Kv4.2 and KChIP2.2 in HeLa cells revealed that mutations on EF-hands did not alter the intracellular co-localization of KChIP2.2 and Kv4.2. Together with previous findings that EF-hand mutants of KChIP proteins are unable to regulate the kinetics of Kv4.2, our data show that the intact EF-hands should be crucial for the formation of active conformation of KChIP2.2 when the protein is loaded with Ca(2+) and Mg(2+).
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
1875-5305
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
16
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1081-7
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Functional roles of EF-hands in human potassium channel-interacting protein 2.2.
pubmed:affiliation
Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't