The role of PTIP in maintaining embryonic stem cell pluripotency.
Pax transactivation domain-interacting protein (PTIP) is a ubiquitously expressed, nuclear protein that is part of a histone H3K4 methyltransferase complex and is essential for embryonic development. Methylation of H3K4 is an epigenetic mark found on many critical developmental regulatory genes in embryonic stem (ES) cells and, together with H3K27 methylation, constitutes a bivalent epigenetic signature. To address the function of PTIP in ES cells, we generated ES cell lines from a floxed ptip allele and deleted PTIP function with Cre recombinase. The ptip(-/-) ES cell lines exhibited a high degree of spontaneous differentiation to trophectoderm and a loss of pluripotency. Reduced levels of Oct4 expression and H3K4 methylation were observed. Upon differentiation, ptip(-/-) embryoid bodies showed reduced levels of marker gene expression for all three primary germ layers. These results suggest that the maintenance of H3K4 methylation is essential and requires PTIP function during the in vitro propagation of pluripotent ES cells.
Kim
Doyeob
D
Department of Pathology, University of Michigan, Ann Arbor, Michigan 48109, USA.
Patel
Sanjeevkumar R
SR
Xiao
Hong
H
Dressler
Gregory R
GR
D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics / Q000502:physiology; D015153:Blotting, Western; D002352:Carrier Proteins / Q000235:genetics / Q000502:physiology*; D002454:Cell Differentiation; D002478:Cells, Cultured; D047369:Chromatin Immunoprecipitation; D004268:DNA-Binding Proteins; D053595:Embryonic Stem Cells / Q000166:cytology* / Q000378:metabolism*; D005260:Female; D006657:Histones / Q000378:metabolism; D007150:Immunohistochemistry; D008297:Male; D008745:Methylation; D051379:Mice; D008817:Mice, Mutant Strains; D009687:Nuclear Proteins / Q000235:genetics / Q000502:physiology*; D050814:Octamer Transcription Factor-3 / Q000235:genetics / Q000502:physiology; D039904:Pluripotent Stem Cells / Q000166:cytology* / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction
D051792:Basic Helix-Loop-Helix Proteins; D002352:Carrier Proteins; D004268:DNA-Binding Proteins; D006657:Histones; D009687:Nuclear Proteins; D050814:Octamer Transcription Factor-3; C095572:Hand1 protein, mouse; C412792:Paxip1 protein, mouse; C494174:Pou5f1 protein, mouse