Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
1993-12-28
pubmed:abstractText
We identified a heterozygous missense mutation that substituted aspartic acid (GAC) for alanine (GCC) at codon 1048 of the insulin receptor gene in a patient who displayed typical symptoms of Type A syndrome of insulin resistance. The proband's mother and younger brother were also found to be heterozygous for the mutation. We constructed the identified mutant insulin receptor cDNA by site-directed mutagenesis, transfected the mutant cDNA into COS 7 cells, and found that kinase activity of the mutant insulin receptors was markedly impaired. Ala1048 is located in the kinase domain of the insulin receptor beta-subunit and is conserved in most of protein-tyrosine kinases. Besides, neighboring Glu1047 is invariant in all protein kinases and is thought to be involved in interaction with ATP. Photoaffinity labeling of the mutant insulin receptor with ATP analogue, 8-azido (alpha-32P)ATP was not influenced by the mutation, suggesting that the mutation did not inhibit ATP binding but possibly interfered with subsequent phosphoryl transfer. Insulin-stimulated phosphorylation of exogenous substrate by partially purified insulin receptors prepared from COS 7 cells that were cotransfected with wild-type and mutant insulin receptor cDNAs was markedly impaired, whereas autophosphorylation was decreased by approximately 50% of wild-type receptors. These results indicated that the identified heterozygous substitution of Asp for Ala1048 in insulin receptor was responsible for insulin resistance of this patient.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0012-1797
pubmed:author
pubmed:issnType
Print
pubmed:volume
42
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1837-44
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed-meshheading:8243830-Adolescent, pubmed-meshheading:8243830-Adult, pubmed-meshheading:8243830-Alanine, pubmed-meshheading:8243830-Amino Acid Sequence, pubmed-meshheading:8243830-Animals, pubmed-meshheading:8243830-Aspartic Acid, pubmed-meshheading:8243830-Base Sequence, pubmed-meshheading:8243830-Cell Line, pubmed-meshheading:8243830-Codon, pubmed-meshheading:8243830-Female, pubmed-meshheading:8243830-Humans, pubmed-meshheading:8243830-Insulin, pubmed-meshheading:8243830-Insulin Resistance, pubmed-meshheading:8243830-Kinetics, pubmed-meshheading:8243830-Lymphocytes, pubmed-meshheading:8243830-Male, pubmed-meshheading:8243830-Middle Aged, pubmed-meshheading:8243830-Mutagenesis, Site-Directed, pubmed-meshheading:8243830-Point Mutation, pubmed-meshheading:8243830-Receptor, Insulin, pubmed-meshheading:8243830-Transfection
pubmed:year
1993
pubmed:articleTitle
Ala1048-->Asp mutation in the kinase domain of insulin receptor causes defective kinase activity and insulin resistance.
pubmed:affiliation
First Department of Medicine, Toyama Medical and Pharmaceutical University, Japan.
pubmed:publicationType
Journal Article, Case Reports, Research Support, Non-U.S. Gov't