Linked Life Data

14631068

Source:http://linkedlifedata.com/resource/pubmed/id/14631068

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2003-11-21
pubmed:abstractText
Calcineurin (CN) is a heterodimer protein consisting of a 61 kDa catalytic subunit A and a 19 kDa regulatory subunit B. It plays a critical role in T-cell activation and is involved in many cellular processes. Regulation of CN is rather complex, including a number of factors such as divalent metal ions (primarily Ca(2+) and Mn(2+)), calmodulin (CaM) and autoinhibition (AI) segment. Previously, we reported that a loop 7 deletion mutant (V314) in subunit A exhibited high phosphatase activity, although the mechanism for the surprising activity enhancement and whether the activity change applies to other loop 7 residues were not known. In order to probe the role of loop 7, we have carried out extensive mutagenesis experiments, followed by systematic activity assays under a number of regulatory conditions. All mutants, including single deletion mutants Y315, N316 and double deletion mutant V314Y315, showed increased phosphatase activity. Significantly, activities of the mutants containing the V314 deletion, namely V314 and V314Y315, were no longer regulated by regulatory subunit B. These results, along with the structure analysis, suggest that loop 7 as a whole plays an important role in mediating CN's regulation through bridging the regulatory subunit and catalytic core and interaction with the AI segment of CN.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0269-2139
pubmed:author
pubmed:issnType
Print
pubmed:volume
16
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
795-8
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
The role of loop 7 in mediating calcineurin regulation.
pubmed:affiliation
Department of Biochemistry and Molecular Biology, Life Science Institute, Beijing Normal University, Beijing 100875, China.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't