Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2000-12-13
pubmed:abstractText
Phosphoinositide 3-kinases produce 3'-phosphorylated phosphoinositides that act as second messengers to recruit other signalling proteins to the membrane. Pi3ks are activated by many extracellular stimuli and have been implicated in a variety of cellular responses. The Pi3k gene family is complex and the physiological roles of different classes and isoforms are not clear. The gene Pik3r1 encodes three proteins (p85 alpha, p55 alpha and p50 alpha) that serve as regulatory subunits of class IA Pi3ks (ref. 2). Mice lacking only the p85 alpha isoform are viable but display hypoglycaemia and increased insulin sensitivity correlating with upregulation of the p55 alpha and p50 alpha variants. Here we report that loss of all protein products of Pik3r1 results in perinatal lethality. We observed, among other abnormalities, extensive hepatocyte necrosis and chylous ascites. We also noted enlarged skeletal muscle fibres, brown fat necrosis and calcification of cardiac tissue. In liver and muscle, loss of the major regulatory isoform caused a great decrease in expression and activity of class IA Pi3k catalytic subunits; nevertheless, homozygous mice still displayed hypoglycaemia, lower insulin levels and increased glucose tolerance. Our findings reveal that p55 alpha and/or p50 alpha are required for survival, but not for development of hypoglycaemia, in mice lacking p85 alpha.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1061-4036
pubmed:author
pubmed:issnType
Print
pubmed:volume
26
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
379-82
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed-meshheading:11062485-Abnormalities, Multiple, pubmed-meshheading:11062485-Adipose Tissue, Brown, pubmed-meshheading:11062485-Animals, pubmed-meshheading:11062485-Animals, Outbred Strains, pubmed-meshheading:11062485-Calcinosis, pubmed-meshheading:11062485-Cardiomyopathies, pubmed-meshheading:11062485-Catalysis, pubmed-meshheading:11062485-Chylous Ascites, pubmed-meshheading:11062485-Crosses, Genetic, pubmed-meshheading:11062485-Dimerization, pubmed-meshheading:11062485-Enzyme Induction, pubmed-meshheading:11062485-Female, pubmed-meshheading:11062485-Genes, pubmed-meshheading:11062485-Genes, Lethal, pubmed-meshheading:11062485-Genotype, pubmed-meshheading:11062485-Germ-Free Life, pubmed-meshheading:11062485-Glucose, pubmed-meshheading:11062485-Hypertrophy, pubmed-meshheading:11062485-Hypoglycemia, pubmed-meshheading:11062485-Insulin, pubmed-meshheading:11062485-Liver, pubmed-meshheading:11062485-Male, pubmed-meshheading:11062485-Mice, pubmed-meshheading:11062485-Mice, Inbred C57BL, pubmed-meshheading:11062485-Mice, Inbred ICR, pubmed-meshheading:11062485-Mice, Knockout, pubmed-meshheading:11062485-Muscle Fibers, Skeletal, pubmed-meshheading:11062485-Necrosis, pubmed-meshheading:11062485-Phosphatidylinositol 3-Kinases, pubmed-meshheading:11062485-Phosphorylation, pubmed-meshheading:11062485-Protein Isoforms, pubmed-meshheading:11062485-Protein Processing, Post-Translational, pubmed-meshheading:11062485-Protein Subunits, pubmed-meshheading:11062485-Second Messenger Systems
pubmed:year
2000
pubmed:articleTitle
Hypoglycaemia, liver necrosis and perinatal death in mice lacking all isoforms of phosphoinositide 3-kinase p85 alpha.
pubmed:affiliation
Division of Signal Transduction, Beth Israel Deaconess Medical Center Boston, Massachusetts, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't