文摘
We have developed a two-dimensional capillary electrophoresis method for the study of protein expression insingle mammalian cells. The first-dimension capillarycontains an SDS-pullulan buffer system to performcapillary sieving electrophoresis, which separates proteinsbased on molecular weight. The second-dimension capillary contains an SDS buffer for micellar electrokineticcapillary chromatography. After a 6-min-long preliminaryseparation, fractions from the first capillary are successively transferred to a second capillary, where theyundergo further separation by MECC. Over 100 transfersand second-dimension separations are performed over an~3.5-h-long period. We demonstrate this technology bygenerating protein fingerprints from single native MC3T3-E1 osteoprogenitor cells and MC3T3-E1 cells transfectedwith the human transcription regulator TWIST. We alsopresent single-cell protein fingerprints from MCF-7 breastcancer cells before and following treatment to induceapoptosis.