Conservation of helical bundle structure between the exocyst subunits.
Conservation of helical bundle structure between the exocyst subunits.
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DOI：
10.1371/journal.pone.0004443
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发表时间：
2009
期刊：
影响因子：
3.7
通讯作者：
Munson M
中科院分区：
文献类型：
--
作者：
Croteau NJ;Furgason ML;Devos D;Munson M
在真核细胞中，外囊是调节分泌囊泡与质膜的靶向和融合所必需的一种大的异八聚体蛋白质复合体。尽管8个不同胞囊亚基之间的序列同源性不到10%，但其中4个亚基的结构域结构显示出相似的螺旋束拓扑结构。由于缺乏用于生化和结构研究的可溶性蛋白质，这些亚基中的几个亚基的特性受到了阻碍。利用改进的隐马尔可夫模型结合二级结构预测，我们检测到每个胞囊亚基之间存在显著的序列相似性，表明它们都含有螺旋束结构。我们通过鉴定和纯化酵母菌Sec10p的预测结构域来证实这些遥远的同源性预测，酵母Sec10p是一种以前不能溶解的胞外囊亚单位。该结构域具有约60%的α螺旋度，是可溶的和折叠的，与我们的预测一致，并能够与几个已知的Sec10p结合伙伴相互作用。尽管所有8个胞外囊亚单位都被认为是由相似的螺旋束组成，但这一点现在已经被我们的隐马尔可夫模型结构预测所验证。此外，这些预测确定了胞外囊亚基中的蛋白质结构域，导致了Sec10p可溶的折叠结构域的创建和表征。
The exocyst is a large hetero-octomeric protein complex required for regulating the targeting and fusion of secretory vesicles to the plasma membrane in eukaryotic cells. Although the sequence identity between the eight different exocyst subunits is less than 10%, structures of domains of four of the subunits revealed a similar helical bundle topology. Characterization of several of these subunits has been hindered by lack of soluble protein for biochemical and structural studies. Using advanced hidden Markov models combined with secondary structure predictions, we detect significant sequence similarity between each of the exocyst subunits, indicating that they all contain helical bundle structures. We corroborate these remote homology predictions by identifying and purifying a predicted domain of yeast Sec10p, a previously insoluble exocyst subunit. This domain is soluble and folded with approximately 60% α-helicity, in agreement with our predictions, and capable of interacting with several known Sec10p binding partners. Although all eight of the exocyst subunits had been suggested to be composed of similar helical bundles, this has now been validated by our hidden Markov model structure predictions. In addition, these predictions identified protein domains within the exocyst subunits, resulting in creation and characterization of a soluble, folded domain of Sec10p.
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影响因子：
5.6
作者：
Hamburger, ZA;Hamburger, AE;Weis, WI
通讯作者：
Weis, WI
影响因子：
16.8
作者：
Dong, G;Hutagalung, AH;Reinisch, KM
通讯作者：
Reinisch, KM
影响因子：
16.2
作者：
Hsu, SC;Hazuka, CD;Scheller, RH
通讯作者：
Scheller, RH
DOI：
10.1073/pnas.0506345103
发表时间：
2006-02-14
影响因子：
11.1
作者：
Devos, D;Dokudovskaya, S;Sali, A
通讯作者：
Sali, A
影响因子：
11.4
作者：
Fukai, S;Matern, HT;Brunger, AT
通讯作者：
Brunger, AT