Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
32
pubmed:dateCreated
2005-8-8
pubmed:databankReference
pubmed:abstractText
The GCN2 protein kinase coordinates protein synthesis with levels of amino acid stores by phosphorylating eukaryotic translation initiation factor 2. The autoinhibited form of GCN2 is activated in cells starved of amino acids by binding of uncharged tRNA to a histidyl-tRNA synthetase-like domain. Replacement of Arg-794 with Gly in the PK domain (R794G) activates GCN2 independently of tRNA binding. Crystal structures of the GCN2 protein kinase domain have been determined for wild-type and R794G mutant forms in the apo state and bound to ATP/AMPPNP. These structures reveal that GCN2 autoinhibition results from stabilization of a closed conformation that restricts ATP binding. The R794G mutant shows increased flexibility in the hinge region connecting the N- and C-lobes, resulting from loss of multiple interactions involving Arg794. This conformational change is associated with intradomain movement that enhances ATP binding and hydrolysis. We propose that intramolecular interactions following tRNA binding remodel the hinge region in a manner similar to the mechanism of enzyme activation elicited by the R794G mutation.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
12
pubmed:volume
280
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
29289-99
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:15964839-Adenosine Triphosphate, pubmed-meshheading:15964839-Amino Acid Sequence, pubmed-meshheading:15964839-Arginine, pubmed-meshheading:15964839-Binding Sites, pubmed-meshheading:15964839-Crystallography, X-Ray, pubmed-meshheading:15964839-Dimerization, pubmed-meshheading:15964839-Escherichia coli, pubmed-meshheading:15964839-Histidine, pubmed-meshheading:15964839-Hydrolysis, pubmed-meshheading:15964839-Magnesium, pubmed-meshheading:15964839-Models, Molecular, pubmed-meshheading:15964839-Molecular Sequence Data, pubmed-meshheading:15964839-Mutation, pubmed-meshheading:15964839-Phosphorylation, pubmed-meshheading:15964839-Protein Binding, pubmed-meshheading:15964839-Protein Conformation, pubmed-meshheading:15964839-Protein Kinases, pubmed-meshheading:15964839-Protein Structure, Tertiary, pubmed-meshheading:15964839-Protein-Serine-Threonine Kinases, pubmed-meshheading:15964839-RNA, Transfer, pubmed-meshheading:15964839-Saccharomyces cerevisiae, pubmed-meshheading:15964839-Saccharomyces cerevisiae Proteins, pubmed-meshheading:15964839-Sequence Homology, Amino Acid, pubmed-meshheading:15964839-eIF-2 Kinase
pubmed:year
2005
pubmed:articleTitle
Structural basis for autoinhibition and mutational activation of eukaryotic initiation factor 2alpha protein kinase GCN2.
pubmed:affiliation
Structural GenomiX, Inc., San Diego, CA 92121, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural