A missense mutation in ftsZ differentially affects vegetative and developmentally controlled cell division in Streptomyces coelicolor A3(2)
A missense mutation in ftsZ differentially affects vegetative and developmentally controlled cell division in Streptomyces coelicolor A3(2)
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DOI：
10.1046/j.1365-2958.2003.03334.x
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发表时间：
2003-02-01
影响因子：
3.6
通讯作者：
Flärdh, L
中科院分区：
文献类型：
--
作者：
Grantcharova, N;Ubhayasekera, W;Flärdh, L
链霉菌coeticoiorA3(2)至少经历两种类型的细胞分裂：营养分裂导致底物菌丝体的交叉壁；在气生菌丝中发育调控孢子的分离。通过分离和鉴定一个不产孢的ftsZ突变体，我们证明了两种类型的分离之间的差异。ftsZ17（Spo）等位基因产生了典型的白色表型。突变体在平板上的生长和亲本一样好，并形成了明显正常的菌丝交叉壁，尽管频率略有下降。相比之下，孢子分离几乎完全被消除，导致表型让人想起h和ftsZDelta2p突变体。ftsZ17（Spo）等位基因部分显性，对细胞FtsZ含量无显著影响。从FtsZ的免疫荧光显微镜和FtsZ与egfp的翻译融合来看，突变阻止了孢子菌丝中Z环的正确时空组装。对S. coelicolor FtsZ的同源性建模表明，突变（c端结构域的A249T变化）可能会改变FtsZ原丝侧面的蛋白质。结果表明，在S. coelicolor A3孢子形成过程中，细胞分裂可能在z环组装水平上受到发育控制(2)。
Streptomyces coeticoiorA3(2) undergoes at least two kinds of cell division: vegetative septation leading to cross-walls in the substrate mycelium; and developmentally regulated sporulation septation in aerial hyphae. By isolation and characterization of a non-sporulating ftsZ mutant, we demonstrate a difference between the two types of septation. The ftsZ17(Spo) allele gave rise to a classical white phenotype. The mutant grew as well as the parent on plates, and formed apparently normal hyphal cross-walls, although with a small reduction in frequency. In contrast, sporulation septation was almost completely abolished, resulting in a phenotype reminiscent of whiH and ftsZDelta2p mutants. The ftsZ17(Spo) allele was partially dominant and had no detectable effect on the cellular FtsZ content. As judged from both immunofluorescence microscopy of FtsZ and translational fusion of ftsZ to egfp, the mutation prevented correct temporal and spatial assembly of Z rings in sporulating hyphae. Homology modelling of S. coelicolor FtsZ indicated that the mutation, an A249T change in the C-terminal domain, would be expected to alter the protein on the lateral face of FtsZ protofilaments. The results suggest that cytokinesis may be developmentally controlled at the level of Z-ring assembly during sporulation of S. coelicolor A3(2).