HETEROGENEITY OF TUBULIN SUBUNITS
HETEROGENEITY OF TUBULIN SUBUNITS
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DOI：
10.1073/pnas.68.9.2028
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发表时间：
1971-01-01
影响因子：
11.1
通讯作者：
SHELANSKI, ML
中科院分区：
文献类型：
--
作者：
FEIT, H;SLUSAREK, L;SHELANSKI, ML
微管蛋白是微管的亚基蛋白，是一种二聚体，在6S处沉积，分子量为110，000。用高分辨率聚丙烯酰胺凝胶电泳，我们已经证明存在两个肽链，分子量为56,000和53,000，在从脑中纯化的微管蛋白。从海胆精子鞭毛中分离的A-和B-微管蛋白中鉴定出两条分子量相似的肽链。在所有情况下，条带中的蛋白浓度相等。当从凝胶中洗脱并在相同类型的凝胶中再次电泳时，每个亚基作为单一条带运行。纯化的脑微管蛋白经DEAE-Sephadex柱层析后，只得到一个含有等量两种亚基的单一峰，经聚丙烯酰胺凝胶洗脱后，从每条带制备溴化氰肽。虽然某些肽似乎是共同的两个亚基，它们之间存在实质性的差异。微管蛋白二聚体由两个不同的亚基组成。
Tubulin, the subunit protein of microtubules, is a dimer that sediments at 6 S and has a molecular weight of 110,000. Using high resolution polyacrylamide gel electrophoresis, we have demonstrated the presence of two peptide chains, of molecular weight 56,000 and 53,000, in tubulin purified from brain. Two peptide chains of similar molecular weight were identified in each of the A- and B-tubulins isolated from flagella of sea urchin sperm. In all cases, the protein concentrations in the bands were equal. Each of the subunits ran as a single band when eluted from the gel and electrophoresed again in the same type of gel. Chromatography of purified brain tubulin on DEAE-Sephadex columns gave only a single peak containing both subunits in equal amounts.Cyanogen bromide peptides were prepared from each of the bands after elution from polyacrylamide gel. While certain of the peptides appear to be common to both subunits, substantial differences exist between them. The tubulin dimer is composed of two nonidentical subunits.