The transcription factor Oct4/Pou5f1 is a component of the regulatory circuitry governing pluripotency and is widely used to induce pluripotency from somatic cells. Here we used domain swapping and mutagenesis to study Oct4's reprogramming ability, identifying a redox-sensitive DNA binding domain, cysteine residue (Cys48), as a key determinant of reprogramming and differentiation. Oct4 Cys48 sensitizes the protein to oxidative inhibition of DNA binding activity and promotes oxidation-mediated protein ubiquitylation. Pou5f1^C48S point mutation has little effect on undifferentiated embryonic stem cells (ESCs) but upon retinoic acid (RA) treatment causes retention of Oct4 expression, deregulated gene expression, and aberrant differentiation. Pou5f1^C48S ESCs also form less differentiated teratomas and contribute poorly to adult somatic tissues. Finally, we describe Pou5f1^C48S (Janky) mice, which in the homozygous condition are severely developmentally restricted after E4.5. Rare animals bypassing this restriction appear normal at birth but are sterile. Collectively, these findings uncover a novel Oct4 redox mechanism involved in both entry into and exit from pluripotency.

中文翻译：

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Oct4 氧化还原敏感性增强重编程和分化


转录因子 Oct4/Pou5f1 是控制多能性的调节电路的一个组成部分，广泛用于诱导体细胞的多能性。在这里，我们使用结构域交换和诱变来研究 Oct4 的重编程能力，识别出氧化还原敏感的 DNA 结合结构域半胱氨酸残基 (Cys48)，作为重编程和分化的关键决定因素。 Oct4 Cys48 使蛋白质对 DNA 结合活性的氧化抑制敏感，并促进氧化介导的蛋白质泛素化。 Pou5f1 ^C48S 点突变对未分化胚胎干细胞 (ESC) 影响不大，但在视黄酸 (RA) 处理后会导致 Oct4 表达保留、基因表达失调和异常分化。 Pou5f1 ^C48S ESC 也会形成分化程度较低的畸胎瘤，并且对成体体组织的贡献很小。最后，我们描述了 Pou5f1 ^C48S (Janky) 小鼠，其在纯合条件下在 E4.5 后发育受到严重限制。绕过这一限制的稀有动物在出生时表现正常，但不育。总的来说，这些发现揭示了一种新的 Oct4 氧化还原机制，涉及多能性的进入和退出。