Nucleation and polymerization of MreB, the bacterial otholog of actin

肌动蛋白在真核细胞的许多细胞方面起着几个关键作用。许多原核细胞含有肌动蛋白的近亲，称为MreB，它与肌动蛋白具有许多保守的特性，也是许多细菌生存所必需的。因此，肌动蛋白和MreB起源于一种进化上古老的促细胞生成蛋白，它已经分化，在所有类型的细胞中实现了一系列令人惊讶的动态和静态功能。枯草芽孢杆菌MreB被研究为原核MreB蛋白的模型，并且已经显示对于细胞周期进展和细胞形状维持是必需的。我们已经发现，它定位为动态螺旋丝下的细胞膜，这似乎是通过棘轮样机制延伸/收缩。现在我们能够在体外研究MreB的聚合，已经产生了功能性的strep标签版本。在拟议的财团内，我们计划研究MreB丝的成核和延伸特性，因为肌动蛋白的原核对应部分的信息将揭示这种蛋白质的进化保守特性的重要光。我们发现MreB与翻译延伸因子EF-Tu相互作用，影响翻译延伸特性，并希望进一步研究这种重要的相互作用。我们发现，三个B。枯草杆菌MreB旁系同源物具有显著不同的细丝结构，并计划通过诱变和SPP 1464聚生体中可用的各种技术来剖析这种独特的现象。

Actin plays several key roles in many cellular aspects of eukaryotic cells. Many prokaryotic cells contain a close relative of actin, called MreB, which shares many conserved properties with actin, and is also essential for viability in many bacteria. Thus, actin and MreB have originated from an evolutionarily ancient filament-forming protein, which has diverged to fulfil an amazing spectrum of dynamic as well as static functions in all kinds of cells. Bacillus subtilis MreB is studied as a model for prokaryotic MreB proteins, and has been shown to be essential for cell cycle progression and for cell shape maintenance. We have found that it localizes as dynamic helical filaments underneath the cell membrane, which appear to extend/retract by a ratchet-like mechanism. Now we are able to study the polymerization of MreB in vitro, having generated a functional strep-tag version. Within the proposed consortium, we plan to study nucleation and extension properties of MreB filaments, because information on the prokaryotic counter part of actin will shed important light onto the evolutionary conserved properties of this protein. We have found that MreB interacts with translation elongation factor EF-Tu, which affects filamentation properties, and want to further study this important interaction. We have found that the three B. subtilis MreB paralogs have strikingly different filament architectures, and plan to dissect this unique phenomenon by mutagenesis and a variety of techniques available within the SPP 1464 consortium.