Armas-Portela R, Kremer L, Avila J
Centro de Biología Molecular (CSIC-UAM), Universidad Autónoma de Madrid, Spain.
Acta Histochem Suppl. 1991;41:37-43.
The centromere of mitotic chromosomes organizes the kinetochore, a proteinaceous matrix that interfaces with spindle microtubules at one plane and with the centromeric DNA at the other. Antibodies present in the sera from patients with CREST scleroderma recognize several proteins localized to the centromere. We have studied the ability of the two main human centromere proteins CENP-A (18 kD) and CENP-B (80 kD) to bind tubulin, in order to correlate with one of the putative functional roles in spindle microtubule attachment. CENP-A was partially solubilized from nuclear extracts by high salt treatment and then purified by reverse phase HPLC. CENP-B was obtained by gel electrophoresis and electroelution from nuclear insoluble extracts. CENP-B binds to tubulin while no significant interaction was found for CENP-A. CENP-B binds to the C-terminal region of tubulin, a characteristic similar to that found for other better characterized microtubule-associated proteins.
有丝分裂染色体的着丝粒组织形成动粒，动粒是一种蛋白质基质，在一个平面上与纺锤体微管相连，在另一个平面上与着丝粒DNA相连。CREST硬皮病患者血清中的抗体可识别几种定位于着丝粒的蛋白质。我们研究了两种主要的人类着丝粒蛋白CENP - A（18 kD）和CENP - B（80 kD）与微管蛋白结合的能力，以便与纺锤体微管附着中一种假定的功能作用相关联。通过高盐处理从核提取物中部分溶解CENP - A，然后通过反相高效液相色谱法进行纯化。CENP - B通过凝胶电泳和从核不溶性提取物中电洗脱获得。CENP - B与微管蛋白结合，而未发现CENP - A有明显相互作用。CENP - B与微管蛋白的C末端区域结合，这一特征与其他特征更明确的微管相关蛋白相似。
