Aviles F J, Danby S E, Chapman G E, Crane-Robinson C, Bradbury E M
Biochim Biophys Acta. 1979 Jun 19;578(2):290-6. doi: 10.1016/0005-2795(79)90159-4.
Trypsin digestion is used to investigate the conformation of histone H5 when bound to DNA. A central region of H5 comprising residues (22--100) is found to be resistant to digestion and it is concluded that this region is compacted whilst the remaining N- and C-terminal regions are more extended. Since this is the same result found previously for the free solution conformation of histone H5 it follows that a 3-domain structure is preserved on DNA binding. The binding of H5 and the central region (22--100) to DNA is also studied using proton magnetic resonance (270 MHz) and a precipitation approach. It is concluded that all 3 domains of H5 bind to DNA at low ionic strengths. The central domain (residues 22--100) is released at 0.3--0.4 M NaCl, but 0.7 M NaCl is required to release the N- and C-terminal regions. Comparison is made of H5 binding to DNA with that of the related histone H1.
胰蛋白酶消化法用于研究组蛋白H5与DNA结合时的构象。发现H5包含残基（22 - 100）的中央区域对消化具有抗性，由此得出结论，该区域是紧密的，而其余的N端和C端区域则更伸展。由于这与先前在组蛋白H5的游离溶液构象中发现的结果相同，因此可以得出结论，在与DNA结合时，其3结构域结构得以保留。还使用质子磁共振（270 MHz）和沉淀法研究了H5及其中央区域（22 - 100）与DNA的结合。得出的结论是，在低离子强度下，H5的所有3个结构域都与DNA结合。中央结构域（残基22 - 100）在0.3 - 0.4 M NaCl浓度下会释放，但需要0.7 M NaCl才能释放N端和C端区域。对H5与DNA的结合以及相关组蛋白H1与DNA的结合进行了比较。
