Model of myosin node aggregation into a contractile ring: the effect of local alignment.
Model of myosin node aggregation into a contractile ring: the effect of local alignment.
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DOI：
10.1088/0953-8984/23/37/374103
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发表时间：
2011-09-21
期刊：
影响因子：
--
通讯作者：
Vavylonis D
中科院分区：
文献类型：
--
作者：
Ojkic N;Wu JQ;Vavylonis D
肌球蛋白束通常通过膜结合的肌球蛋白簇聚集而形成。一个这样的例子是在分裂酵母中，从一条宽阔的皮质结节带形成收缩环。节点是包含几十个肌球蛋白-II分子和几个福尔明二聚体的大分子复合体。以前已经用搜索、捕获、拉和释放(SCPR)模型描述了将宽频带节点凝聚成收缩环的过程。在SCPR中，由福尔马林成核的肌动蛋白细丝介导的随机搜索过程导致节点之间瞬时的肌动球蛋白连接，这些连接相互拉成一个环。SCPR模型再现了节点在长距离上的运输，并预测了在突变体中观察到的成束不稳定性。然而，该模型不能像在一些野生型和突变细胞中观察到的那样，在环组装过程中产生瞬时的线性元件和网状结构。作为节点比对的最小模型，我们在SCPR模型中增加了短程对齐力，代表了目前尚未解决的机制，这些机制可能涉及结构成分、交联和绑定蛋白质。数值研究了局部节点对齐机制对环形成的影响。我们改变了新的参数，找到了符合实际值范围的可行环。在形态上，在环组装过程中形成的瞬时结构类似于在野生型和CDC25-22细胞实验中观察到的结构。我们的工作支持环自组织的分级过程，包括从细胞的远处部分拉到一起的组件，然后逐渐稳定。
Actomyosin bundles frequently form through aggregation of membrane-bound myosin clusters. One such example is the formation of the contractile ring in fission yeast from a broad band of cortical nodes. Nodes are macromolecular complexes containing several dozens of myosin-II molecules and a few formin dimers. The condensation of a broad band of nodes into the contractile ring has been previously described by a search, capture, pull and release (SCPR) model. In SCPR, a random search process mediated by actin filaments nucleated by formins leads to transient actomyosin connections among nodes that pull one another into a ring. The SCPR model reproduces the transport of nodes over long distances and predicts observed clump-formation instabilities in mutants. However, the model does not generate transient linear elements and meshwork structures as observed in some wild-type and mutant cells during ring assembly. As a minimal model of node alignment, we added short-range aligning forces to the SCPR model representing currently unresolved mechanisms that may involve structural components, cross-linking and bundling proteins. We studied the effect of the local node alignment mechanism on ring formation numerically. We varied the new parameters and found viable rings for a realistic range of values. Morphologically, transient structures that form during ring assembly resemble those observed in experiments with wild-type and cdc25-22 cells. Our work supports a hierarchical process of ring self-organization involving components drawn together from distant parts of the cell followed by progressive stabilization.
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影响因子：
3.3
作者：
Coffman, Valerie C.;Nile, Aaron H.;Wu, Jian-Qiu
通讯作者：
Wu, Jian-Qiu
影响因子：
2
作者：
Backouche, F.;Haviv, L.;Bernheim-Groswasser, A.
通讯作者：
Bernheim-Groswasser, A.
影响因子：
4
作者：
Cytrynbaum, EN;Rodionov, V;Mogilner, A
通讯作者：
Mogilner, A
DOI：
10.1038/nrm2834
发表时间：
2010-02
期刊：
Nature reviews. Molecular cell biology
影响因子：
--
作者：
通讯作者：
--
影响因子：
4.8
作者：
ISAMBERT, H;VENIER, P;CARLIER, MF
通讯作者：
CARLIER, MF