RESUMO
Pluripotency is a unique biological state that allows cells to differentiate into any tissue type. Here we describe a candidate pluripotency factor, Ronin, that possesses a THAP domain, which is associated with sequence-specific DNA binding and epigenetic silencing of gene expression. Ronin is expressed primarily during the earliest stages of murine embryonic development, and its deficiency in mice produces periimplantational lethality and defects in the inner cell mass. Conditional knockout of Ronin prevents the growth of ES cells while forced expression of Ronin allows ES cells to proliferate without differentiation under conditions that normally do not promote self-renewal. Ectopic expression also partly compensates for the effects of Oct4 knockdown. We demonstrate that Ronin binds directly to HCF-1, a key transcriptional regulator. Our findings identify Ronin as an essential factor underlying embryogenesis and ES cell pluripotency. Its association with HCF-1 suggests an epigenetic mechanism of gene repression in pluripotent cells.
Assuntos
Proteínas de Ligação a DNA/metabolismo , Desenvolvimento Embrionário , Células-Tronco Embrionárias/citologia , Células-Tronco Pluripotentes/citologia , Animais , Diferenciação Celular , Linhagem Celular , Proteínas de Ligação a DNA/genética , Implantação do Embrião , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Expressão Gênica , Genes Letais , Fator C1 de Célula Hospedeira/metabolismo , Camundongos , Proteínas Repressoras , Técnicas do Sistema de Duplo-HíbridoRESUMO
Induced pluripotent stem cells (iPSCs) hold enormous potential for the development of personalized in vitro disease models, genomic health analyses, and autologous cell therapy. Here we describe the generation of T lymphocyte-derived iPSCs from small, clinically advantageous volumes of non-mobilized peripheral blood. These T-cell derived iPSCs ("TiPS") retain a normal karyotype and genetic identity to the donor. They share common characteristics with human embryonic stem cells (hESCs) with respect to morphology, pluripotency-associated marker expression and capacity to generate neurons, cardiomyocytes, and hematopoietic progenitor cells. Additionally, they retain their characteristic T-cell receptor (TCR) gene rearrangements, a property which could be exploited for iPSC clone tracking and T-cell development studies. Reprogramming T-cells procured in a minimally invasive manner can be used to characterize and expand donor specific iPSCs, and control their differentiation into specific lineages.