Assembly properties of two CNBr fragments of avian desmin that correspond to the headpiece domain and helix 1B.
Assembly properties of two CNBr fragments of avian desmin that correspond to the headpiece domain and helix 1B.
复制标题
对应于头结构域和螺旋 1B 的禽类结蛋白的两个 CNBr 片段的组装特性。
DOI：
10.1016/0006-291x(89)92709-5
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发表时间：
1989
影响因子：
3.1
通讯作者：
Ip,W
中科院分区：
文献类型：
--
作者：
Saeed,T;Ip,W
为了研究肌肉特异的中间丝蛋白desmin的不同结构域对其聚合的影响，在组装条件下检测了其两个CNBR片段的寡聚体结构。其中一个，D88，覆盖残基1-88，几乎代表整个头盔；另一个，D109，覆盖残基145-254，包括完整分子的整个螺旋1B和部分连接子L12。化学交联、SDS-PAGE和分析凝胶过滤表明，在10 mM Tris-HCl、pH 8.5的条件下，有利于完整结蛋白D88四聚的条件只形成二聚体。另一方面，D109主要形成二聚体物种，但也检测到少量的三聚体和四聚体物种。这些数据与以下假设一致，即在将完整的蛋白质分子组装成IF时，头盔和螺旋1有助于将两个多肽二聚化成平行的、注册的螺旋线圈。然而，为了稳定四聚体和全尺寸IF，还需要额外的相互作用，包括头-棒结合和整个杆域上的疏水相互作用。
To study how different domains of the muscle-specific intermediate filament protein, desmin, contribute to its polymerization, two of its CNBr fragments were examined as to their oligomeric structure under assembly conditions. One of these, D88, covers residues 1–88 and represents almost the entire headpiece; the other, D109, covers residues 145–254, and includes the entire Helix 1B and part of linker L12of the intact molecule. Chemical cross-linking followed by SDS-PAGE, and analytical gel filtration, revealed that in 10 mM Tris-HCl, pH 8.5, conditions that favor tetramerization of intact desmin D88 formed only dimers. D109, on the other hand, formed primarily a dimeric species but low levels of trimeric and tetrameric species were also detectable. These data are consistent with the proposal that, during assembly of intact protein molecules into IF, the headpiece and Helix 1 contribute to dimerization of two polypeptides into a parallel, in-register coiled-coil. However, additional interactions, including headpiece-to-rod binding and hydrophobic interaction along the entire rod domain, are required to stabilize the tetramers and full-size IF.