Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1990-3-7
pubmed:abstractText
Several proteins in mammalian cells are modified post-translationally by the isoprenoid, farnesol. Incubation of cultured cells with [3H]mevalonate, an isoprenoid precursor, results in the labeling of multiple polypeptides, the most prominent of which migrate in the range of 21-26 kDa on sodium dodecyl sulfate-polyacrylamide gels. In Rat-6 fibroblasts transformed by H-ras, one of the farnesylated proteins was identified as p21ras by two-dimensional immunoblotting. However, this protein accounted for only a small proportion of the [3H]mevalonate-derived radioactivity incorporated into 21-26-kDa proteins. Murine erythroleukemia cells, which did not express immunodetectable quantities of p21ras, contained several 21-26-kDa farnesylated proteins distributed in both the cytosolic and particulate fractions. At least eight of these proteins were capable of binding [alpha-32P]GTP on nitrocellulose membranes. Pulse-chase studies showed that the isoprenoid modification did not necessarily result in the translocation of the cytosolic proteins to the cell membrane. A prominent group of carboxyl-methylated proteins in murine erythroleukemia cells overlapped with the 21-26-kDa farnesylated proteins on one-dimensional sodium dodecyl sulfate gels. Methylation of this group of proteins was selectively abolished when cells were treated with lovastatin, an inhibitor of isoprenoid synthesis. Addition of exogenous mevalonate to the lovastatin-treated cells fully restored carboxyl methylation. These studies suggest that the 21-26-kDa farnesylated proteins in mammalian cells are members of a recently discovered family of low molecular mass GTP-binding proteins which, although ras-related, appear to be distinct structurally and possibly functionally from the products of the ras genes. The observed isoprenoid-dependent carboxyl methylation of a group of 21-26-kDa proteins suggests that the low molecular mass GTP-binding proteins may undergo a series of post-translational C-terminal cysteine modifications (i.e. farnesylation, carboxyl methylation) analogous to those recently elucidated for p21ras.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
265
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2148-55
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:2105317-Animals, pubmed-meshheading:2105317-Cell Line, pubmed-meshheading:2105317-Cell Membrane, pubmed-meshheading:2105317-Cytosol, pubmed-meshheading:2105317-Electrophoresis, Gel, Two-Dimensional, pubmed-meshheading:2105317-Electrophoresis, Polyacrylamide Gel, pubmed-meshheading:2105317-GTP-Binding Proteins, pubmed-meshheading:2105317-Guanosine Triphosphate, pubmed-meshheading:2105317-Immunoblotting, pubmed-meshheading:2105317-Leukemia, Erythroblastic, Acute, pubmed-meshheading:2105317-Lovastatin, pubmed-meshheading:2105317-Methylation, pubmed-meshheading:2105317-Mevalonic Acid, pubmed-meshheading:2105317-Mice, pubmed-meshheading:2105317-Molecular Weight, pubmed-meshheading:2105317-Protein Binding, pubmed-meshheading:2105317-Protein Processing, Post-Translational, pubmed-meshheading:2105317-Rats
pubmed:year
1990
pubmed:articleTitle
Post-translational modification of low molecular mass GTP-binding proteins by isoprenoid.
pubmed:affiliation
Weis Center for Research, Geisinger Clinic, Danville, Pennsylvania 17822.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.