Nucleation and polymerization of MreB, the bacterial otholog of actin

肌动蛋白细菌同源物 MreB 的成核和聚合

• 批准号: 170443292
• 负责人: Professor Dr. Peter Graumann
• 金额: --
• 依托单位: Zentrum für Synthetische Mikrobiologie (SYNMIKRO)
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2010
• 资助国家: 德国
• 起止时间: 2009-12-31 至 2013-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/170443292?language=en
• 关键词: Nucleation; polymerization; MreB; bacterial; otholog

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.

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纤维形成蛋白，这种蛋白在各种细胞中已经分化，以实现惊人的动态和静态功能。枯草芽孢杆菌MreB被研究为原核MreB蛋白的模型，并已被证明对细胞周期进程和细胞形状维持至关重要。我们发现它定位为细胞膜下的动态螺旋状细丝，似乎通过棘轮状机制伸展/收缩。现在我们能够在体外研究MreB的聚合，已经产生了一个功能性的链球菌标签版本。在拟议的联盟中，我们计划研究MreB细丝的成核和延伸特性，因为关于肌动蛋白的原核对抗部分的信息将为该蛋白的进化保守特性提供重要的启示。我们发现MreB与翻译延伸因子EF-Tu相互作用，影响成丝性能，并希望进一步研究这一重要的相互作用。我们发现三个枯草芽孢杆菌MreB相似物具有明显不同的丝结构，并计划通过诱变和SPP 1464联盟中可用的各种技术来解剖这种独特的现象。