Cobbe Neville, Heck Margarete M S
Wellcome Trust Centre for Cell Biology, University of Edinburgh, Michael Swann Building, King's Buildings, Edinburgh, United Kingdom.
Proteins. 2006 May 15;63(3):685-96. doi: 10.1002/prot.20795.
The SMC (structural maintenance of chromosomes) proteins are a highly conserved and ubiquitous family of ATPases, found in nearly all living organisms examined, where they play crucial roles in transmission of the hereditary material. However, the extent to which efficient ATP hydrolysis is required for SMC function has been a matter of some debate. Here we investigate the potential functional significance of ATP binding and hydrolysis in different eukaryotic SMC proteins, both by comparing the conservation of conserved ATPase motifs and by exploring potential coevolution between associated domains. In this way, we have been able to account for the reduced requirement for ATPase activity in cohesin's SMC3 and demonstrate the greater apparent conservation requirements for such activity in condensin SMC proteins. Finally, we explore possible interactions between the SMC and non-SMC components of the condensin complex that are required for full condensin activity and may modulate ATPase activity in the holocomplex.
染色体结构维持（SMC）蛋白是一类高度保守且普遍存在的ATP酶家族，在几乎所有已检测的生物中都能找到，它们在遗传物质的传递中发挥着关键作用。然而，SMC功能对高效ATP水解的需求程度一直存在一些争议。在这里，我们通过比较保守ATP酶基序的保守性以及探索相关结构域之间的潜在协同进化，研究了不同真核生物SMC蛋白中ATP结合和水解的潜在功能意义。通过这种方式，我们能够解释黏连蛋白的SMC3对ATP酶活性需求的降低，并证明凝缩蛋白SMC蛋白对这种活性有更高的明显保守性要求。最后，我们探讨了凝缩蛋白复合物的SMC和非SMC成分之间可能的相互作用，这些相互作用是凝缩蛋白完全活性所必需的，并且可能调节全复合物中的ATP酶活性。
