Nucleotide-dependent control of internal strains in ring-shaped AAA+ motors.
Nucleotide-dependent control of internal strains in ring-shaped AAA+ motors.
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DOI：
10.1007/s12195-012-0264-5
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发表时间：
2013-03-01
影响因子：
2.8
通讯作者：
Lang, Matthew J.
中科院分区：
文献类型：
--
作者：
Hwang, Wonmuk;Lang, Matthew J.
AAA+（与各种细胞活动相关的 ATP 酶）机械代表了一种极其成功且广泛使用的生物马达设计计划。最近发现的晶体结构开始揭示 AAA+ 马达的标准六聚环中核苷酸依赖性构象变化。然而，ATP 结合在一个亚基上变构传播到整个环的物理机制仍有待发现。在这里，我们分析和比较了三种环形 AAA+ 电机 ClpX、HslU 和 dynein 的结构组织。通过使用相同构象的亚基构建多聚体，我们发现各个亚基局部具有不同螺距、半径、手性和对称数的螺旋几何形状。这些结果表明，ATP 与亚基的结合施加了构象限制，必须通过更灵活的无核苷酸亚基来适应，以减轻环上的机械应变。环轮廓的局部变形和随后的应变传播可能是 AAA+ 电机在实现功能多样性的同时产生力的通用策略。
The AAA+ (ATPase Associated with various cellular Activities) machinery represents an extremely successful and widely used design plan for biological motors. Recently found crystal structures are beginning to reveal nucleotide-dependent conformational changes in the canonical hexameric rings of the AAA+ motors. However, the physical mechanism by which ATP binding on one subunit allosterically propagates across the entire ring remains to be found. Here we analyze and compare structural organization of three ring-shaped AAA+ motors, ClpX, HslU, and dynein. By constructing multimers using subunits of identical conformations, we find that individual subunits locally possess helical geometries with varying pitch, radius, chirality, and symmetry number. These results suggest that binding of an ATP to a subunit imposes conformational constraint that must be accommodated by more flexible nucleotide-free subunits to relieve mechanical strain on the ring. Local deformation of the ring contour and subsequent propagation of strains may be a general strategy that AAA+ motors adopt to generate force while achieving functional diversity.
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影响因子：
2.6
作者：
Hwang, Wonmuk;Lang, Matthew J.
通讯作者：
Lang, Matthew J.
影响因子：
64.5
作者：
Aubin-Tam ME;Olivares AO;Sauer RT;Baker TA;Lang MJ
通讯作者：
Lang MJ
影响因子：
3
作者：
BROOKS, BR;BRUCCOLERI, RE;KARPLUS, M
通讯作者：
KARPLUS, M
影响因子：
6.8
作者：
Lyubimov, Artem Y.;Strycharska, Melania;Berger, James M.
通讯作者：
Berger, James M.
DOI：
10.1073/pnas.0904756106
发表时间：
2009-10-27
影响因子：
11.1
作者：
Koga, Nobuyasu;Kameda, Tomoshi;Takada, Shoji
通讯作者：
Takada, Shoji