title: Proteomic Analysis of Mouse Oocytes Identifies PRMT7 as a Reprogramming Factor that Replaces SOX2 in the Induction of Pluripotent Stem Cells.
abstract: The reprogramming process that leads to induced pluripotent stem cells (iPSCs) may benefit from adding oocyte factors to Yamanaka's reprogramming cocktail (OCT4, SOX2, KLF4, with or without MYC; OSK(M)). We previously searched for such facilitators of reprogramming (the reprogrammome) by applying label-free LC-MS/MS analysis to mouse oocytes, producing a catalog of 28 candidates that are (i) able to robustly access the cell nucleus and (ii) shared between mature mouse oocytes and pluripotent embryonic stem cells. In the present study, we hypothesized that our 28 reprogrammome candidates would also be (iii) abundant in mature oocytes, (iv) depleted after the oocyte-to-embryo transition, and (v) able to potentiate or replace the OSKM factors. Using LC-MS/MS and isotopic labeling methods, we found that the abundance profiles of the 28 proteins were below those of known oocyte-specific and housekeeping proteins. Of the 28 proteins, only arginine methyltransferase 7 (PRMT7) changed substantially during mouse embryogenesis and promoted the conversion of mouse fibroblasts into iPSCs. Specifically, PRMT7 replaced SOX2 in a factor-substitution assay, yielding iPSCs. These findings exemplify how proteomics can be used to prioritize the functional analysis of reprogrammome candidates. The LC-MS/MS data are available via ProteomeXchange with identifier PXD003093.
authors.affiliation: Key Laboratory of Farm Animal Genetic Resources and Germplasm Innovation of Ministry of Agriculture, Institute of Animal Science, Chinese Academy of Agricultural Sciences , Beijing 100193, China.
authors.forename: Bingyuan
authors.initials: B
authors.lastname: Wang
authors.affiliation: Max Planck Institute for Molecular Biomedicine , Röntgenstraße 20, 48149 Münster, Germany.
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Pfeiffer
authors.affiliation: Max Planck Institute for Molecular Biomedicine , Bioanalytical Mass Spectrometry Facility, Röntgenstraße 20, 48149 Münster, Germany.
authors.forename: Hannes C A
authors.initials: HC
authors.lastname: Drexler
authors.affiliation: Institute for Biostatistics and Informatics in Medicine and Ageing Research, Rostock University Medical Center, 18057 Rostock, Germany.
authors.forename: Georg
authors.initials: G
authors.lastname: Fuellen
authors.affiliation: Max Planck Institute for Molecular Biomedicine , Röntgenstraße 20, 48149 Münster, Germany.
authors.forename: Michele
authors.initials: M
authors.lastname: Boiani
mesh_terms: D000818:Animals; D065150:Cellular Reprogramming; D002853:Chromatography, Liquid; D047108:Embryonic Development; D005347:Fibroblasts / Q000166:cytology; D057026:Induced Pluripotent Stem Cells / Q000166:cytology; D000090062:Kruppel-Like Factor 4; D051379:Mice; D009865:Oocytes / Q000737:chemistry*; D039904:Pluripotent Stem Cells / Q000166:cytology; D011484:Protein-Arginine N-Methyltransferases / Q000502:physiology*; D040901:Proteomics / Q000379:methods; D055748:SOXB1 Transcription Factors / Q000502:physiology*; D053719:Tandem Mass Spectrometry
chemical_list: C000715468:Klf4 protein, mouse; D000090062:Kruppel-Like Factor 4; D055748:SOXB1 Transcription Factors; C527783:Sox2 protein, mouse; C570798:PRMT7 protein, mouse; D011484:Protein-Arginine N-Methyltransferases
keywords: DNMT3A; PRMT7; SILAC; STELLA; development; induced pluripotent stem cells; oocyte proteome; reprogramming; reprogrammome