The linker histone Hho1 modulates the activity of ATP-dependent chromatin remodeling complexes
The linker histone Hho1 modulates the activity of ATP-dependent chromatin remodeling complexes
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DOI：
10.1016/j.bbagrm.2021.194781
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发表时间：
2022-01-06
影响因子：
4.7
通讯作者：
Gutierrez, Jose L.
中科院分区：
文献类型：
--
作者：
Amigo, Roberto;Farkas, Carlos;Gutierrez, Jose L.
多种因素在染色质动力学中起作用，包括连接蛋白。其中有高迁移率族（HMG）盒家族蛋白和连接组蛋白。在酿酒酵母（Saccharomyces cerevisiae）中，Hmo1已被鉴定为一种HMG - 盒蛋白。这种蛋白表现出与这种归类相符的特性。然而，一些研究推测Hmo1在酵母中作为一种连接组蛋白发挥作用。另一方面，当被发现时，Hho1蛋白被鉴定为一种连接组蛋白。虽然多项研究支持这种分类，但一些发现指出Hho1的特征与通常归属于连接组蛋白的那些特征不同。为了更好地理解Hmo1和Hho1在染色质动力学和转录调控中所起的作用，我们进行了几项分析，直接对这两种蛋白进行比较。我们对全基因组结合谱的分析支持Hmo1属于HMGB家族以及Hho1属于连接组蛋白家族。有趣的是，通过进行蛋白质 - 蛋白质相互作用分析，我们发现Hmo1和Hho1都与ATP依赖的染色质重塑复合物RSC、ISW1a和SWI/SNF有物理相互作用。此外，通过进行核小体重塑实验，我们发现这两种蛋白都刺激ISW1a复合物的活性。然而，对于RSC来说，Hmo1和Hho1表现出不同的特性，Hho1主要表现出抑制作用。我们的结果与RSC和ISW1a在染色质动力学和转录调控中所起的相反作用相符，并拓宽了对Hho1和连接组蛋白所起作用的认识。
Diverse factors play roles in chromatin dynamics, including linker proteins. Among them are high mobility group (HMG) box family proteins and linker histones. In the yeast Saccharomyces cerevisiae, Hmo1 has been identified as an HMG-box protein. This protein displays properties that are in agreement with this allocation. However, a number of studies have postulated that Hmo1 functions as a linker histone in yeast. On the other hand, when discovered, the Hho1 protein was identified as a linker histone. While multiple studies support this classification, some findings point to characteristics of Hho1 that are dissimilar to those commonly assigned to linker histones. In order to better understand the roles played by Hmo1 and Hho1 in chromatin dynamics and transcriptional regulation, we performed several analyses directly comparing these two proteins. Our analyses of genome-wide binding profiles support the belonging of Hmo1 to the HMGB family and Hho1 to the linker histones family. Interestingly, by performing protein-protein interaction analyses we found that both Hmo1 and Hho1 display physical interaction with the ATP-dependent chromatin remodeling complexes RSC, ISW1a and SWI/SNF. Moreover, by carrying out nucleosome remodeling assays, we found that both proteins stimulate the activity of the ISW1a complex. However, in the case of RSC, Hmo1 and Hho1 displayed differential properties, with Hho1 mainly showing an inhibitory effect. Our results are in agreement with the opposite roles played by RSC and ISW1a in chromatin dynamics and transcriptional regulation, and expand the view for the roles played by Hho1 and linker histones.