Identification of p21Cip1 binding proteins by gel electrophoresis and capillary liquid chromatography microelectrospray tandem mass spectrometry.
Proteins bound to a glutathione-S-transferase-p21Cip1 affinity column were separated by one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis and identified using tandem mass spectrometry. Capillary liquid chromatography coupled to microelectrospray tandem mass spectrometry (capLC-microESI MS/MS) in an ion trap allowed identification of the proteins present in the gel bands. Of eleven bands analyzed, fifty-three proteins were identified. More than one hundred tryptic peptides were detected on-line, automatically fragmented and used for protein characterization in databases. Samples were also analyzed by off-line nanospray and matrix-assisted laser desorption/ionization mass spectrometry. CapLC-microESI MS/MS was the most efficient technique for the analysis of these protein mixtures.
Carrascal
Montserrat
M
Department of Medical Bioanalysis, IIBB-CSIC, IDIBAPS, Barcelona, Spain.
Carujo
Sonia
S
Bachs
Oriol
O
Abian
Joaquin
J
D000595:Amino Acid Sequence; D002845:Chromatography; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins / Q000737:chemistry / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D008969:Molecular Sequence Data; D010455:Peptides / Q000032:analysis; D011506:Proteins / Q000032:analysis*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000295:instrumentation / Q000379:methods*
D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D010455:Peptides; D011506:Proteins