Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, Bethesda, MD 20892, USA.
Science. 2013 May 31;340(6136):1110-3. doi: 10.1126/science.1235532.
Chromosome segregation during mitosis requires assembly of the kinetochore complex at the centromere. Kinetochore assembly depends on specific recognition of the histone variant CENP-A in the centromeric nucleosome by centromere protein C (CENP-C). We have defined the determinants of this recognition mechanism and discovered that CENP-C binds a hydrophobic region in the CENP-A tail and docks onto the acidic patch of histone H2A and H2B. We further found that the more broadly conserved CENP-C motif uses the same mechanism for CENP-A nucleosome recognition. Our findings reveal a conserved mechanism for protein recruitment to centromeres and a histone recognition mode whereby a disordered peptide binds the histone tail through hydrophobic interactions facilitated by nucleosome docking.
有丝分裂过程中的染色体分离需要在着丝粒处组装动粒复合物。动粒组装依赖于中心体蛋白 C(CENP-C)对着丝粒核小体中组蛋白变体 CENP-A 的特异性识别。我们已经确定了这种识别机制的决定因素,并发现 CENP-C 结合 CENP-A 尾部的一个疏水区,并与组蛋白 H2A 和 H2B 的酸性斑结合。我们进一步发现,更为广泛保守的 CENP-C 基序使用相同的机制识别 CENP-A 核小体。我们的研究结果揭示了一种用于蛋白招募到着丝粒的保守机制,以及一种组蛋白识别模式,其中无序肽通过核小体对接促进的疏水相互作用结合组蛋白尾部。