Duncan Elizabeth M
Department of Biology, University of Kentucky, Lexington, Kentucky, USA.
J Biol Chem. 2025 May 15;301(7):110239. doi: 10.1016/j.jbc.2025.110239.
Histone proteolysis is sometimes described as an extreme posttranslational modification (PTM), as it removes both a stretch of histone sequence and any PTMs that were previously added to it. Such an acute and significant loss of information could trigger many different downstream effects, making it attractive as a mechanism for rapid gene silencing or activation. However, protease activity is challenging to study and is often treated like background noise that is best kept as low as possible. As both histones and protease activity are highly abundant in most cells, evidence of proteolysis of histone tails-a.k.a. histone clipping-has often been dismissed as nonspecific noise. Yet over the past decades there have been studies suggesting this activity should not be ignored, that it may represent a rare but relevant process with important roles in cell biology. Here, I review the key studies that both support this argument and raise additional questions about the mechanisms and functions of histone clipping.
组蛋白水解有时被描述为一种极端的翻译后修饰(PTM),因为它既去除了一段组蛋白序列,也去除了先前添加到其上的任何PTM。如此急剧且显著的信息丢失可能引发许多不同的下游效应,使其成为快速基因沉默或激活的一种有吸引力的机制。然而,蛋白酶活性难以研究,并且常常被视为背景噪声,最好尽可能保持在低水平。由于组蛋白和蛋白酶活性在大多数细胞中都高度丰富,组蛋白尾部水解的证据——也就是组蛋白剪切——常常被当作非特异性噪声而不予理会。然而在过去几十年里,有研究表明这种活性不应被忽视,它可能代表了一个罕见但相关的过程,在细胞生物学中具有重要作用。在此,我回顾了支持这一观点的关键研究,并对组蛋白剪切的机制和功能提出了更多问题。