The Anchored Flexibility Model in LC8 Motif Recognition: Insights from the Chica Complex.
The Anchored Flexibility Model in LC8 Motif Recognition: Insights from the Chica Complex.
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DOI：
10.1021/acs.biochem.5b01099
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发表时间：
2016-01-12
期刊：
影响因子：
2.9
通讯作者：
Barbar E
中科院分区：
文献类型：
--
作者：
Clark S;Nyarko A;Löhr F;Karplus PA;Barbar E
LC 8是一种二聚体枢纽蛋白，参与细胞功能的大量相互作用。它结合短的线性基序-通常含有一个Thr-Gln-Thr（TQT）三联体-在其结合配偶体的固有无序区域，其中一些具有串联的几个LC 8识别基序。7-10个氨基酸基序的特征是LC 8结合亲和力的高度可变性和TQT三联体外的广泛序列排列。为了阐明基序识别的分子基础，我们使用了一个69个残基的人类Chica纺锤体衔接蛋白，其中包含四个假定的TQT识别基序串联。NMR衍生的二级化学位移和弛豫性质表明，Chica LC 8结合结构域基本上是无序的，在一个连接基序之间的动态限制性片段。LC 8与合成基序模拟肽结合的量热法显示，第一个基序主导LC 8募集。与两个基序肽中的每一个结合的LC 8的复合物的晶体结构显示出高度有序和不变的TQT-LC 8相互作用以及更灵活和构象可变的非TQT-LC 8相互作用。这些数据突出了结合TQT的LC 8残基和基序的TQT部分中的刚性作为LC 8识别的重要新特征。基于这些数据和文献中的其他数据，我们提出LC 8识别是基于LC 8和TQT残基之间的刚性固定的相互作用，其充当锚，再加上LC 8和非TQT残基之间固有的灵活相互作用。“锚定的灵活性”模型解释了TQT三联体的需要和LC 8容纳大量不同基序序列和亲和力的能力。
LC8 is a dimeric hub protein involved in a large number of interactions central to cell function. It binds short linear motifs—usually containing a Thr-Gln-Thr (TQT) triplet—in intrinsically disordered regions of its binding partners, some of which have several LC8 recognition motifs in tandem. Hallmarks of the 7–10 amino acid motif are a high variability of LC8 binding affinity and extensive sequence permutation outside the TQT triplet. To elucidate the molecular basis of motif recognition, we use a 69-residue segment of the human Chica spindle adaptor protein that contains four putative TQT recognition motifs in tandem. NMR-derived secondary chemical shifts and relaxation properties show that the Chica LC8 binding domain is essentially disordered with a dynamically restricted segment in one linker between motifs. Calorimetry of LC8 binding to synthetic motif-mimicking peptides shows that the first motif dominates LC8 recruitment. Crystal structures of the complexes of LC8 bound to each of two motif peptides show highly ordered and invariant TQT-LC8 interactions and more flexible and conformationally variable non-TQT-LC8 interactions. These data highlight rigidity in both LC8 residues that bind TQT and in the TQT portion of the motif as an important new characteristic of LC8 recognition. On the basis of these data and others in the literature, we propose that LC8 recognition is based on rigidly fixed interactions between LC8 and TQT residues that act as an anchor, coupled with inherently flexible interactions between LC8 and non-TQT residues. The “anchored flexibility” model explains the requirement for the TQT triplet and the ability of LC8 to accommodate a large variety of motif sequences and affinities.
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影响因子：
5.6
作者：
Benison, Gregory;Karplus, P. Andrew;Barbar, Elisar
通讯作者：
Barbar, Elisar
DOI：
10.1083/jcb.201111041
发表时间：
2012-07-09
期刊：
The Journal of cell biology
影响因子：
--
作者：
Gupta A;Diener DR;Sivadas P;Rosenbaum JL;Yang P
通讯作者：
Yang P
DOI：
10.1083/jcb.200807155
发表时间：
2009-04-20
期刊：
The Journal of cell biology
影响因子：
--
作者：
Fejtova A;Davydova D;Bischof F;Lazarevic V;Altrock WD;Romorini S;Schöne C;Zuschratter W;Kreutz MR;Garner CC;Ziv NE;Gundelfinger ED
通讯作者：
Gundelfinger ED
影响因子：
4.8
作者：
Jurado, Sabine;Conlan, Lindus A.;Heierhorst, Joerg
通讯作者：
Heierhorst, Joerg
DOI：
10.1107/s0907444909052925
发表时间：
2010-02
期刊：
Acta crystallographica. Section D, Biological crystallography
影响因子：
--
作者：
Adams PD;Afonine PV;Bunkóczi G;Chen VB;Davis IW;Echols N;Headd JJ;Hung LW;Kapral GJ;Grosse-Kunstleve RW;McCoy AJ;Moriarty NW;Oeffner R;Read RJ;Richardson DC;Richardson JS;Terwilliger TC;Zwart PH
通讯作者：
Zwart PH