Phasing the conformational unit of spectrin.
Phasing the conformational unit of spectrin.
复制标题
血影蛋白构象单元的定相。
DOI：
10.1073/pnas.88.23.10788
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发表时间：
1991
影响因子：
11.1
通讯作者：
Branton,D
中科院分区：
文献类型：
--
作者：
Winograd,E;Hume,D;Branton,D
许多蛋白质包含重复序列基序，这意味着它们包含重复的结构基序。血影蛋白及其相关蛋白dystrophin和α-actinin主要由100-120个残基的重复基序组成。但重复基序是简并的，很难确定重复序列单元或其相应结构单元的边界。我们已经确定了与血影蛋白重复的106个氨基酸基序相对应的结构单元在哪些残基开始和结束。果蝇α-血影蛋白基因在细菌中的表达结果表明，果蝇血影蛋白基因编码区编码的单个片段(106个氨基酸)和成对片段可以折叠成稳定的构象，其生物物理和生化性质与天然的血影蛋白相似。由于这种折叠严重依赖于表达序列相对于重复基序的表观边界的相位，我们的数据提供了将折叠的构象单元的边界与重复基序的化学序列联系起来的实验证据。
Many proteins contain a repetitive sequence motif, which implies that they contain a repetitive structural motif. Spectrin and the related proteins dystrophin and alpha-actinin consist largely of repeated motifs of 100-120 residues. But the repeating motif is degenerate and it has been difficult to define the boundaries of the repeating sequence unit or its corresponding structural unit. We have determined at which residues the structural units that correspond to spectrin's repeating 106-amino acid motifs begin and end. Drosophila alpha-spectrin cDNAs were expressed in bacteria to show that single segments (106 amino acids) and pairs of segments encoded by selected regions of spectrin cDNA can fold into stable conformations whose biophysical and biochemical properties are similar to those of native spectrin. Because such folding was critically dependent on the phasing of the expressed sequence with respect to the apparent boundaries of the repeating motifs, our data provide experimental evidence that relates the boundaries of the folded, conformational unit to the chemical sequence of repeating motifs.