Lessons from the stem cell proteome.
The proteome of a cell is a molecular fingerprint directly relating to the gene expression snapshot profile at a certain point of time or developmental stage. Monitoring the expansion and the differentiation state of stem cells by proteomic means seems therefore a very attractive method for diagnostic as well as for therapeutic purposes. We have investigated the protein expression patterns of umbilical cord blood-derived CD34+/AC133+ cells in order to obtain a most comprehensive view of the stem cell proteome. For this purpose, we have applied 2-D gel electrophoresis and 2-D chromatography for most efficient protein/peptide separation and characterisation. The proteins were identified after tryptic digestion by nano-HPLC coupled directly to an ion trap mass spectrometer. An extensive bioinformatic analysis of the protein obtained revealed a dynamic stem cell proteome. This means that the heterogeneity of protein expression patterns obtained from different stem cell preparations refers to a limited set of stem cell-specific house keeping proteins as well as to a large number of proteins which depend on (marginal) stimuli from the environment. Since those are difficult to standardise, snapshot views of the stem cell proteome reflect not only stem cell-intrinsic metabolism but also the strong influence of the sample history on protein expression patterns.
Gesslbauer
Bernd
B
Institute of Pharmaceutical Sciences, University of Graz, A-8010 Graz, Austria.
Krenn
Evelyn
E
Zenzmaier
Christoph
C
Preisegger
Karl-Heinz
KH
Kungl
Andreas J
AJ
D000328:Adult; D002648:Child; D002675:Child, Preschool; D003598:Cytoskeletal Proteins / Q000235:genetics / Q000302:isolation & purification; D015180:Electrophoresis, Gel, Two-Dimensional; D004622:Embryo, Mammalian; D004798:Enzymes / Q000235:genetics / Q000302:isolation & purification; D005312:Fetal Blood / Q000166:cytology* / Q000502:physiology; D006801:Humans; D007231:Infant, Newborn; D013058:Mass Spectrometry; D008565:Membrane Proteins / Q000235:genetics / Q000302:isolation & purification; D009687:Nuclear Proteins / Q000235:genetics / Q000302:isolation & purification; D011506:Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D040901:Proteomics; D013234:Stem Cells / Q000502:physiology*
D003598:Cytoskeletal Proteins; D004798:Enzymes; D008565:Membrane Proteins; D009687:Nuclear Proteins; D011506:Proteins