Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
43
pubmed:dateCreated
1991-12-2
pubmed:abstractText
Limited proteolysis of tyrosine hydroxylase (TH) by calpain, Ca(2+)-activated neutral protease, was studied. Cleavage of TH with calpain in vitro produced molecules having Mrs of approximately 57,000 and 56,000 in SDS-polyacrylamide gel electrophoresis. The N-terminal amino acid sequence, Ser-Pro-Arg-Phe-Val, of the 56-kDa species indicated that calpain cleaved off the N-terminal region (residues 1-30) encoded by the first exon including Ser-8 and Ser-19, the phosphorylation sites by proline-directed protein kinase (PDPK) and by Ca2+/calmodulin-dependent protein kinase II (kinase II), respectively, from the native TH. The removal of the N-terminal region from the native molecule induced a slight but significant activation of TH at pH 7.0. The native TH behaved as the tetramer with an Mr of 240,000. In contrast, calpain-cleaved TH showed the monomeric Mr by gel permeation chromatography and increased Ki for catecholamine which inhibits the native TH in competition to the coenzyme, DL-6-methyl-5,6,7,8-tetrahydropterin (6MPH4). These results imply that calpain cleavage would effectively release TH from the feedback inhibition by removal of the N-terminal region resulting in disruption of the quaternary structure.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
29
pubmed:volume
30
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
10416-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Limited proteolysis of tyrosine hydroxylase by Ca(2+)-activated neutral protease (calpain).
pubmed:affiliation
Radioisotope Center Medical Division, Nagoya University School of Medicine, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't