Mutational and functional analysis in human Ras/MAP kinase genetic syndromes.
The Ras/mitogen-activated protein kinase (MAPK) pathway is essential in regulation of the cell cycle, cell differentiation, growth, and cell senescence, each of which are critical to normal development. A class of developmental disorders, the "RASopathies," is caused by germline mutations in genes that encode protein components of the Ras/MAPK pathway which result in dysregulation of the pathway and profound deleterious effects on development. One of these syndromes, cardiofaciocutaneous (CFC) syndrome, is caused by germline mutations in BRAF, MAP2K1 (MEK1) and MAP2K2 (MEK2), and possibly KRAS genes. Here, we describe the laboratory protocols and methods that we used to identify mutations in BRAF and MEK1/2 genes as causative for CFC syndrome. In addition, we present the techniques used to determine the effect these mutations have on activity of the Ras/MAPK pathway through Western blot analysis of the phosphorylation of endogenous ERK1/2, as well as through the use of an in vitro kinase assay that measures the phosphorylation of Elk-1.
Tidyman
William E
WE
Department of Pediatrics, Division of Medical Genetics, University of California San Francisco, San Francisco, CA, USA.
Rauen
Katherine A
KA
D001483:Base Sequence; D015153:Blotting, Western; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics / Q000302:isolation & purification; D004252:DNA Mutational Analysis / Q000379:methods*; D018076:DNA, Complementary / Q000235:genetics; D004476:Ectodermal Dysplasia / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D057075:Enzyme Assays / Q000379:methods*; D019066:Facies; D005183:Failure to Thrive / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D016678:Genome / Q000235:genetics; D057809:HEK293 Cells; D006330:Heart Defects, Congenital / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D006801:Humans; D048369:MAP Kinase Kinase 1 / Q000235:genetics / Q000378:metabolism; D048370:MAP Kinase Kinase 2 / Q000235:genetics / Q000378:metabolism; D020935:MAP Kinase Signaling System; D017354:Point Mutation; D017346:Protein Serine-Threonine Kinases / Q000235:genetics* / Q000378:metabolism*; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics / Q000378:metabolism; D013577:Syndrome; D014162:Transfection
D018076:DNA, Complementary; D004247:DNA; D017346:Protein Serine-Threonine Kinases; D048493:Proto-Oncogene Proteins B-raf; D048369:MAP Kinase Kinase 1; D048370:MAP Kinase Kinase 2