Proteomic signature of human embryonic stem cells

Abstract

Human embryonic stem cells (hESC) represent a population of undifferentiated pluripotent cells with both self-renewal and multilineage differentiation characteristics. Proteomics provides a powerful approach for studying the characteristics of hESC and discovering molecular markers. We have analyzed proteome profiles of three hESC lines using 2-DE and MALDI TOF-TOF. Out of 844 spots analyzed with MALDI TOF-TOF, 685 proteins were identified of which 60 proteins were classified as the most abundant proteins on 2-D gels. A large number of proteins particularly high abundant ones were identified as chaperones, heat shock proteins, ubiquitin/proteasome, and oxidative stress responsive proteins underscoring the ability of these cells to resist oxidative stress and increase the life span. Several proteins involved in cell proliferation and differentiation were also among the highly expressed proteins. Although overall expression pattern of three hESC were similar, 54 spots changed quantitatively and 14 spots changed qualitatively among the hESC cell lines. Most of these proteins were identified as proteins involved in cell growth, metabolism and signal transduction, which may affect the self-renewal and pluripotency. To our knowledge, this study represents the first proteomic dataset for hESC and provides a better insight into the biology of hESC. Proteome maps of hESC are accessible at http://www.RoyanProteomics.ir.

Distinct cardiogenic preferences of two human embryonic stem cell (hESC) lines are imprinted in their proteomes in the pluripotent state

“…In addition, they were able to verify the presence of these newly identified factors in 3 undifferentiated hESC lines: EES2, HUES-1 and NL-hESC-03 [18]. The second study used conventional 2-D gels to compare the undifferentiated proteomes of the Royan H2, H3 and H5 hESC lines [19]. In the present study, we hypothesized that the H1 and HES2 lines have distinct preferences to become chamber-specific heart cells, and that their different cardiogenic potentials are predetermined at the pluripotent stage due to discrete differences in their proteomes.…”

Mass spectrometry based proteomic analysis of human stem cells: a brief review

“…Careful analysis on all isoforms of a given protein is very important because many of the interesting regulatory steps, especially those involved in cell proliferation, migration and differentiation, count on protein PTM more than they do on protein expression levels (Levchenko, 2005). Baharvand et al (2006b) identified a large number of proteins involved in protein synthesis, processing, and trafficking. Such finding suggests that hESCs are able to maintain the undifferentiated state until signals of lineage determination is received, upon which these cells quickly change phenotype and produce necessary proteins.…”

“…Also, Baharvand et al (2006b) have applied 2-DE and MALDI TOF-TOF MS/MS (4700 Proteomics Analyzer, Applied Biosystems) to profile global map of proteome expressed in hESC. Cell line samples were analyzed in triplicate using 2-DE and 1,250 ± 150 spots were detected.…”

“…Human embryonic stem cells (hESC) consist of a population of undifferentiated pluripotent cells with both self-renewal and multi-lineage differentiation characteristics (Baharvand et al, 2006b). Hayman and Przyborski (2004) reported surface enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS) technology to explore potential biomarkers of human embryonal carcinoma (EC) stem cells.…”

“…Proteomics has emerged as a robust method for comparing protein expression under different conditions that supplements high-throughput gene expression analysis at the RNA level (Baharvand et al, 2006b). Proteomics approaches have been applied to create the molecular map of protein expression in stem cells.…”