The Rockefeller University, New York, NY 10065, USA.
Curr Opin Genet Dev. 2010 Apr;20(2):110-7. doi: 10.1016/j.gde.2010.01.003. Epub 2010 Feb 12.
Histone proteins often come in different variants serving specialized functions in addition to their fundamental role in packaging DNA. The metazoan histone H3.3 has been most closely associated with active transcription. Its role in histone replacement at active genes and promoters is conserved to the single histone H3 in yeast. However, recent genetic studies in flies have challenged its importance as a mark of active chromatin, and revealed unexpected insights into essential functions of H3.3 in the germline. With strikingly little amino acid sequence difference to the canonical H3, H3.3 therefore accomplishes a surprising variety of cellular and developmental processes.
组蛋白蛋白通常有不同的变体，除了在包装 DNA 方面的基本作用外，还具有专门的功能。后生动物组蛋白 H3.3 与活跃的转录最为密切相关。其在活性基因和启动子处组蛋白替换中的作用在酵母中单一的组蛋白 H3 中是保守的。然而，最近在果蝇中的遗传研究对其作为活性染色质标记的重要性提出了挑战，并揭示了 H3.3 在生殖细胞中意想不到的重要功能。由于与典型的 H3 只有很少的氨基酸序列差异，因此 H3.3 完成了惊人的各种细胞和发育过程。
