Coiled-coil trigger motifs in the 1B and 2B rod domain segments are required for the stability of keratin intermediate filaments.
Coiled-coil trigger motifs in the 1B and 2B rod domain segments are required for the stability of keratin intermediate filaments.
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1B 和 2B 杆结构域片段中的卷曲螺旋触发基序对于角蛋白中间丝的稳定性是必需的。
DOI：
10.1091/mbc.11.10.3539
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发表时间：
2000
影响因子：
3.3
通讯作者：
Steinert,PM
中科院分区：
文献类型：
--
作者：
Wu,KC;Bryan,JT;Morasso,MI;Jang,SI;Lee,JH;Yang,JM;Marekov,LN;Parry,DA;Steinert,PM
许多形成双链卷曲螺旋的α-螺旋蛋白具有13个残基的触发基序，该基序似乎是卷曲螺旋稳定所必需的。然而，如目前所定义的，该基序不存在于中间丝（IF）蛋白链中，但其仍然形成分段的双链卷曲螺旋。在目前的工作中，我们已经搜索并确定了IF链中的两个区域，这两个区域对于形成卷曲螺旋分子所必需的稳定性是必不可少的，因此可能起到触发基序的作用。我们用角蛋白5/角蛋白14 IF系统进行了一系列点取代。在体外和体内组装野生型和突变体链的组合，并使用尿素分解试验检查双链（单分子）和双分子组装体的稳定性。我们的新数据文件，有一个区域位于残基100和113之间的2B杆域片段，是绝对需要的分子稳定性和IF组装。这个潜在的触发基序与共有基序略有不同，在4位有一个Asp残基（而不是Glu），在9位有一个Thr残基（而不是带电残基），但在6位绝对需要Glu残基。由于这13个残基是高度保守的，因此似乎可能该基序在所有IF链中起作用。同样地，通过测试角蛋白IF在两条链中的取代，我们确定了第二个潜在的触发基序之间的残基79和91的1B杆结构域片段，这也可能是保守的所有IF链。然而，我们无法找到一个触发基序在1A杆域段。此外，许多其他点的取代几乎没有检测到的影响，IF组装，除了保守的2B杆结构域片段的Lys-23残基。交联和建模研究表明，当两个分子以A22模式排列时，Lys-23可能非常接近Glu-106。因此，Glu-106残基可能在IF结构中具有双重作用：它可能参与触发物形成以向双链卷曲螺旋分子提供特殊稳定性，并且它可能参与IF结构的双分子分级阶段的稳定化。
Many α-helical proteins that form two-chain coiled coils possess a 13-residue trigger motif that seems to be required for the stability of the coiled coil. However, as currently defined, the motif is absent from intermediate filament (IF) protein chains, which nevertheless form segmented two-chain coiled coils. In the present work, we have searched for and identified two regions in IF chains that are essential for the stability necessary for the formation of coiled-coil molecules and thus may function as trigger motifs. We made a series of point substitutions with the keratin 5/keratin 14 IF system. Combinations of the wild-type and mutant chains were assembled in vitro and in vivo, and the stabilities of two-chain (one-molecule) and two-molecule assemblies were examined with use of a urea disassembly assay. Our new data document that there is a region located between residues 100 and 113 of the 2B rod domain segment that is absolutely required for molecular stability and IF assembly. This potential trigger motif differs slightly from the consensus in having an Asp residue at position 4 (instead of a Glu) and a Thr residue at position 9 (instead of a charged residue), but there is an absolute requirement for a Glu residue at position 6. Because these 13 residues are highly conserved, it seems possible that this motif functions in all IF chains. Likewise, by testing keratin IF with substitutions in both chains, we identified a second potential trigger motif between residues 79 and 91 of the 1B rod domain segment, which may also be conserved in all IF chains. However, we were unable to find a trigger motif in the 1A rod domain segment. In addition, many other point substitutions had little detectable effect on IF assembly, except for the conserved Lys-23 residue of the 2B rod domain segment. Cross-linking and modeling studies revealed that Lys-23 may lie very close to Glu-106 when two molecules are aligned in the A22mode. Thus, the Glu-106 residue may have a dual role in IF structure: it may participate in trigger formation to afford special stability to the two-chain coiled-coil molecule, and it may participate in stabilization of the two-molecule hierarchical stage of IF structure.
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通过离子对萃取从蛋白质中去除十二烷基硫酸钠。
影响因子：
--
作者：
W. Konigsberg;L. Henderson
通讯作者：
L. Henderson
DOI：
--
发表时间：
1995
影响因子：
11.1
作者：
A. Letai;E. Fuchs
通讯作者：
E. Fuchs
影响因子：
5.6
作者：
Y. Yu;O. Monera;R. Hodges;P. Privalov
通讯作者：
Y. Yu;O. Monera;R. Hodges;P. Privalov
DOI：
10.1093/protein/7.11.1365
发表时间：
1994-11
期刊：
Protein engineering
影响因子：
--
作者：
N. Zhou;C. Kay;R. Hodges
通讯作者：
N. Zhou;C. Kay;R. Hodges
I 型角蛋白 16 的 α-螺旋杆结构域中的脯氨酸残基使角蛋白异四聚体不稳定*
影响因子：
4.8
作者：
M. Wawersik;R. Paladini;Erick N. Noensie;P. Coulombe
通讯作者：
P. Coulombe