Obligate heterodimerization of the archaeal Alba2 protein with Alba1 provides a mechanism for control of DNA packaging
Obligate heterodimerization of the archaeal Alba2 protein with Alba1 provides a mechanism for control of DNA packaging
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DOI：
10.1016/j.str.2005.04.016
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发表时间：
2005-07-01
期刊：
影响因子：
5.7
通讯作者：
White, MF
中科院分区：
文献类型：
--
作者：
Jelinska, C;Conroy, MJ;White, MF
在高温下生长的生物面临着保持其遗传物质完整性的特殊挑战。所有嗜热和超嗜热古菌编码一个或多个拷贝的Alba（Sac10b）基因。Alba是一种丰富的二聚体高碱性蛋白质，可与DNA以高密度协同结合。硫磺硫化叶菌编码Alba基因的第二个拷贝，并且Alba2蛋白以Alba1水平的5%表达。我们通过NMR、ITC和晶体学证明，在生理浓度下，Alba 2仅以Alba 1的异二聚体形式存在，并且异二聚化对DNA包装产生明显影响，正如EM所观察到的那样，可能是通过改变相邻Alba二聚体之间的界面来实现的。DNA复合物。Alba2在调节高阶染色质结构和DNA凝聚中的功能作用。
Organisms growing at elevated temperatures face a particular challenge to maintain the integrity of their genetic material. All thermophilic and hyperthermophilic archaea encode one or more copies of the Alba (Sac10b) gene. Alba is an abundant, dimeric, highly basic protein that binds cooperatively and at high density to DNA. Sulfolobus solfataricus encodes a second copy of the Alba gene, and the Alba2 protein is expressed at 5% of the level of Alba1. We demonstrate by NMR, ITC, and crystallography that Alba2 exists exclusively as a heterodimer with Alba1 at physiological concentrations and that heterodimerization exerts a clear effect upon the DNA packaging, as observed by EM, potentially by changing the interface between adjacent Alba dimers in DNA complexes. A functional role for Alba2 in modulation, of higher order chromatin structure and DNA condensation is suggested.