title: Partial inhibition of differentiation associated with elevated protein levels of pluripotency factors in mouse embryonic stem cells expressing exogenous EGAM1N homeoprotein.
abstract: We previously reported that transcripts encoding the homeoprotein EGAM1N are expressed in preimplantation mouse embryos and embryonic stem (ES) cells, and the exogenous expression of EGAM1N inhibits the differentiation of ES cells. In order to clarify the relationship between the inhibition of differentiation and EGAM1N, we generated mouse MG1.19 ES cells stably expressing EGAM1N. Control transfectants with an empty vector formed relatively flattened cell colonies similar to those observed in parental MG1.19 cells. In contrast, Egam1n transfectants formed tightly aggregated cell colonies with increased localization of CDH1 at cell-to-cell interfaces. The protein levels of pluripotency factors, including TBX3 and SOX2, were also increased. The expression of Tbx3 transcripts was induced, although the level of Sox2 transcripts was almost unchanged. The expression of EGAM1N resulted in no obvious changes in the expression of genes encoding receptors, protein kinases, transcription factors, and their encoded proteins involved in the LIF-STAT3 signaling pathway. Alkaline phosphatase activity, a marker for the undifferentiated state, in Egam1n transfectants was exhibited in a clonal proliferation assay. When differentiation of Egam1n transfectants was induced, progression was prevented with increases in transcript levels of Pou5f1, Sox2, Nanog, Klf4, Tbx3, and their encoded proteins. However, Egam1n transfectants formed relatively flattened-cell layers as observed in the control, indicating that the expression of EGAM1N could not maintain LIF-independent self-renewal of ES cells. Overall, we suggest that expression of EGAM1N could inhibit differentiation, at least in part, by elevating the protein levels of pluripotency factors in MG1.19 ES cells.
authors.affiliation: Graduate School of Bioresource Sciences, Akita Prefectural University, 241-438 Kaidohbatanishi, Shimoshinjohnakano, Akita 010-0195, Japan.
authors.forename: Shiori
authors.initials: S
authors.lastname: Sato
authors.affiliation: Graduate School of Bioresource Sciences, Akita Prefectural University, 241-438 Kaidohbatanishi, Shimoshinjohnakano, Akita 010-0195, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Nakazawa
authors.affiliation: Graduate School of Bioresource Sciences, Akita Prefectural University, 241-438 Kaidohbatanishi, Shimoshinjohnakano, Akita 010-0195, Japan.
authors.forename: Yumi
authors.initials: Y
authors.lastname: Kihara
authors.affiliation: Graduate School of Bioresource Sciences, Akita Prefectural University, 241-438 Kaidohbatanishi, Shimoshinjohnakano, Akita 010-0195, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Kubo
authors.affiliation: Graduate School of Bioresource Sciences, Akita Prefectural University, 241-438 Kaidohbatanishi, Shimoshinjohnakano, Akita 010-0195, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Sato
authors.affiliation: Graduate School of Bioresource Sciences, Akita Prefectural University, 241-438 Kaidohbatanishi, Shimoshinjohnakano, Akita 010-0195, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Kikuchi
authors.affiliation: Graduate School of Bioresource Sciences, Akita Prefectural University, 241-438 Kaidohbatanishi, Shimoshinjohnakano, Akita 010-0195, Japan.
authors.forename: Asumi
authors.initials: A
authors.lastname: Nonaka
authors.affiliation: Graduate School of Bioresource Sciences, Akita Prefectural University, 241-438 Kaidohbatanishi, Shimoshinjohnakano, Akita 010-0195, Japan; Akita Research Institute of Food and Brewing, 4-26 Sanuki, Araya-machi, Akita 010-1623, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Sasaki
authors.affiliation: Graduate School of Bioresource Sciences, Akita Prefectural University, 241-438 Kaidohbatanishi, Shimoshinjohnakano, Akita 010-0195, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Iwashita
authors.affiliation: Graduate School of Bioresource Sciences, Akita Prefectural University, 241-438 Kaidohbatanishi, Shimoshinjohnakano, Akita 010-0195, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Murata
authors.affiliation: Graduate School of Bioresource Sciences, Akita Prefectural University, 241-438 Kaidohbatanishi, Shimoshinjohnakano, Akita 010-0195, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Hosaka
authors.affiliation: Graduate School of Bioresource Sciences, Akita Prefectural University, 241-438 Kaidohbatanishi, Shimoshinjohnakano, Akita 010-0195, Japan. Electronic address: makoba@akita-pu.ac.jp.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Kobayashi
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D064200:Cdh1 Proteins / Q000378:metabolism; D002454:Cell Differentiation / Q000235:genetics*; D002460:Cell Line; D000066673:Cell Self Renewal; D048430:Cell Shape; D002999:Clone Cells / Q000166:cytology / Q000378:metabolism; D020869:Gene Expression Profiling; D018398:Homeodomain Proteins / Q000235:genetics* / Q000378:metabolism*; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors / Q000235:genetics / Q000378:metabolism; D053605:Leukemia Inhibitory Factor / Q000378:metabolism; D051379:Mice; D000066450:Mouse Embryonic Stem Cells / Q000166:cytology* / Q000378:metabolism*; D000071317:Nanog Homeobox Protein; D050814:Octamer Transcription Factor-3 / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D055748:SOXB1 Transcription Factors / Q000235:genetics / Q000378:metabolism; D050796:STAT3 Transcription Factor / Q000378:metabolism; D015398:Signal Transduction; D020825:T-Box Domain Proteins / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism*; D014162:Transfection
chemical_list: D064200:Cdh1 Proteins; C558397:EGAM1C protein, mouse; C577585:Fzr1 protein, mouse; D018398:Homeodomain Proteins; C000715468:Klf4 protein, mouse; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors; D053605:Leukemia Inhibitory Factor; C507838:Lif protein, mouse; D000071317:Nanog Homeobox Protein; C475540:Nanog protein, mouse; D050814:Octamer Transcription Factor-3; C494174:Pou5f1 protein, mouse; D012333:RNA, Messenger; D055748:SOXB1 Transcription Factors; D050796:STAT3 Transcription Factor; C527783:Sox2 protein, mouse; C494087:Stat3 protein, mouse; D020825:T-Box Domain Proteins; C491460:Tbx3 protein, mouse; D014157:Transcription Factors; D000469:Alkaline Phosphatase
keywords: CRXOS1 isoform c; Crxos tv3; Differentiation; EGAM1N; Embryonic stem cells; Inhibition; Pluripotency factor