title: Human embryonic and mesenchymal stem cells express different nuclear proteomes.
abstract: Human embryonic stem cells (hESCs) are characterized by their immortality and pluripotency. Human mesenchymal stem cells (hMSC), on the other hand, have limited self-renewal and differentiation capabilities. The underlying molecular differences that account for this characteristic self-renewal and plasticity are, however, poorly understood. This study reports a nuclear proteomic analysis of human embryonic and bone marrow-derived mesenchymal stem cells. Our proteomic screen highlighted a 5-fold difference in the expression of Reptin52. We show, using two-dimensional difference gel electrophoresis (2-DIGE), western analysis, and quantitative reverse transcriptase polymerase chain reaction, that Reptin52 is more abundantly expressed in hESC than hMSC. Moreover, we observed differential expression of Pontin52 and beta-catenin-proteins known to interact with Reptin52. This difference in the expression of Reptin52 and Pontin52 (known regulators of beta-catenin) further supports a role for Wnt signaling in stem cell self-renewal and proliferation.
authors.affiliation: Department of Pharmacology, Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA.
authors.forename: Amritha
authors.initials: A
authors.lastname: Jaishankar
authors.forename: Miguel
authors.initials: M
authors.lastname: Barthelery
authors.forename: Willard M
authors.initials: WM
authors.lastname: Freeman
authors.forename: Ugur
authors.initials: U
authors.lastname: Salli
authors.forename: Timothy M
authors.initials: TM
authors.lastname: Ritty
authors.forename: Kent E
authors.initials: KE
authors.lastname: Vrana
mesh_terms: D000074183:ATPases Associated with Diverse Cellular Activities; D000293:Adolescent; D000328:Adult; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism*; D004265:DNA Helicases / Q000235:genetics / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D053595:Embryonic Stem Cells / Q000166:cytology / Q000378:metabolism*; D005260:Female; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D008297:Male; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000378:metabolism*; D053858:Metabolic Networks and Pathways; D020543:Proteome / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D015203:Reproducibility of Results
chemical_list: D002352:Carrier Proteins; D020543:Proteome; D012333:RNA, Messenger; D000074183:ATPases Associated with Diverse Cellular Activities; D004265:DNA Helicases; C122079:RUVBL2 protein, human