Institut Curie, Centre de Recherche, Paris F-75248 Cedex 05, France; CNRS, UMR218, Paris F-75248 Cedex 05, France.
Trends Genet. 2013 Nov;29(11):630-40. doi: 10.1016/j.tig.2013.06.002. Epub 2013 Jul 2.
Animal development and lifetime potential exploit a balance between the stability and plasticity of cellular identity. Within the nucleus, this is controlled by an interplay involving lineage-specific transcription factors and chromatin dynamics. Histone H3 variants contribute to chromatin dynamics through the timing and sites of their incorporation, promoted by dedicated histone chaperones. Moreover, their individual modifications and binding partners provide distinct features at defined genomic loci. We highlight here the importance of the H3.3 replacement variant for the nuclear reprogramming that occurs during gametogenesis, fertilization, and germline establishment. Furthermore, we describe how the recently characterized H3.3 dynamics associated with gastrulation, myogenesis, or neurogenesis underline the role of chromatin changes in cell differentiation. Finally, we discuss the challenges of maintaining centromeric identity through propagation of the centromeric CenH3 variant in different cell types. Future challenges will be to gain a comprehensive picture of H3 variants and their chaperones during development and differentiation.
动物的发育和终生潜能利用了细胞身份稳定性和可塑性之间的平衡。在核内，这种平衡通过涉及谱系特异性转录因子和染色质动力学的相互作用来控制。组蛋白 H3 变体通过其掺入的时间和位置来促进染色质动力学，这是由专门的组蛋白伴侣促进的。此外，它们的个体修饰和结合伙伴在特定的基因组位置提供了独特的特征。在这里，我们强调了 H3.3 替换变体在配子发生、受精和生殖系建立过程中发生的核重编程中的重要性。此外，我们描述了最近描述的与原肠胚形成、肌发生或神经发生相关的 H3.3 动力学如何强调了染色质变化在细胞分化中的作用。最后，我们讨论了通过在不同细胞类型中传播着丝粒 CenH3 变体来维持着丝粒身份所面临的挑战。未来的挑战将是在发育和分化过程中全面了解 H3 变体及其伴侣。
