Multipotent Adult Germline Stem Cells and Embryonic Stem Cells: Comparative Proteomic Approach

Abstract

Spermatogonial stem cells isolated from the adult mouse testis acquire under certain culture conditions pluripotency and become so-called multipotent adult germline stem cells (maGSCs). They can be differentiated into somatic cells of the three germ layers. We investigated a subset of the maGSCs and ESCs proteomes using cell lines derived from two different mouse strains, narrow range immobilized pH gradients to favor the detection of less abundant proteins, and DIGE to ensure confident comparison between the two cell types. 2-D reference maps of maGSCs and ESCs in the pI ranges 3-6 and 5-8 were created, and protein entities were further processed for protein identification. By peptide mass fingerprinting and tandem mass spectrometry combined with searches of protein sequence databases, a set of 409 proteins was identified, corresponding to a library of 166 nonredundant stem cell-associated proteins. The identified proteins were classified according to their main known/postulated functions using bioinformatics. Furthermore, we used DIGE to highlight the ESC-like nature of maGSCs on the proteome scale. We concluded that the proteome of maGSCs is highly similar to that of ESCs as we could identify only a small subset of 18 proteins to be differentially expressed between the two cell types. Moreover, comparative analysis of the cell line proteomes from two different mouse strains showed that the interindividual differences in maGSCs proteomes are minimal. With our study, we created for the first time a proteomic map for maGSCs and compared it to the ESCs proteome from the same mouse. We confirmed on the proteome level the ESC-like nature of maGSCs.

Multipotent Adult Germline Stem Cells and Embryonic Stem Cells Functional Proteomics Revealed an Important Role of Eukaryotic Initiation Factor 5A (Eif5a) in Stem Cell Differentiation

“…Because of the high proteome similarity between the maGSCs and ESCs, 13 DIGE analysis of the cell extracts from the two cell types stimulated with RA was performed. The achieved DIGEgels of the stimulated cells indicated a significant difference in protein pattern, showing that 55 protein spot were differently expressed, when maGSCs/RA was compared to ESCs/RA (Supplemental Figure 1).…”

“…We confirmed on the proteome level the ESC-like nature of maGSCs. 13 To identify new potential pluripotence correlated proteins or differentiation associated proteins, we investigated the effects of retinoic acid (RA) treatment on the protein expression profiles of maGSCs and ESCs and identified proteins potentially involved in the SCs differentiation. We demonstrated the important role of Eif5a in stem cell differentiation and highlighted the role of the hypusination as a stem cell differentiation and cell cycle control step.…”

Global and gene-specific histone modification profiles of mouse multipotent adult germline stem cells

“…mGSCs from adult mouse testis, so-called multipotent adult germline stem cells (maGSCs) were firstly isolated and described by our group. It was recently shown that maGSCs and ESCs express the same clusters of microRNAs (miRNAs; Zovoilis et al, 2008) previously thought to be ESC-specific (Houbaviy et al, 2003) and also share the same proteomic profiles (Dihazi et al, 2009). More recently, another study described similarities between maGSCs and ESCs at the epigenetic level by investigating the DNA methylation status of several imprinted genes, pluripotency marker genes as well as global DNA methylation patterns in the undifferentiated and differentiated state (Zechner et al, 2009).…”

FABP1 and FABP3 Have High Predictive Values for Renal Replacement Therapy in Patients with Acute Kidney Injury

“…Subsequently, protein chloroform/methanol precipitation was carried out according to Wessel and Flugge [23] and protein estimation was performed using the Bio-Rad protein assay according to Bradford [24] . 2-DE and DIGE-analyses were carried out as previously described [25] .…”