在多细胞蓝藻（如Anabaena sp.）中，研究小组发现染色体编码的ParMR系统已经进化成一个名为CorMR的细胞骨架系统，其功能是细胞形状控制而不是DNA分离。活细胞成像、体外重构和低温电镜显示，CorM形成了动态不稳定的反平行双链细丝，这些细丝通过多细胞蓝藻中保守的两亲螺旋被CorR招募到膜上。CorMR细丝受MinC调控，被排除在极和分裂面之外。比较基因组学表明，ParMR和Min系统的再利用与蓝藻的多细胞性共同进化，突出了细菌细胞骨架系统的进化可塑性。
研究人员表示，细菌像真核生物一样，具有保守的细胞骨架系统，用于细胞内组织。质粒编码的ParMRC系统形成肌动蛋白样丝，分离低拷贝数质粒。
附：英文原文
Title: Repurposing of a DNA segregation machinery into a cytoskeletal system controlling cell shape
Author: Benjamin L. Springstein, Manjunath G. Javoor, Daniela Megrian, Roman Hajdu, Dustin M. Hanke, Bettina Zens, Gregor L. Weiss, Florian K. M. Schur, Martin Loose
Issue&Volume: 2026-04-16
Abstract: Bacteria, like eukaryotes, use conserved cytoskeletal systems for intracellular organization. The plasmid-encoded ParMRC system forms actin-like filaments that segregate low–copy number plasmids. In multicellular cyanobacteria such as Anabaena sp., we found that a chromosomally encoded ParMR system has evolved into a cytoskeletal system named CorMR with a function in cell shape control rather than DNA segregation. Live-cell imaging, in vitro reconstitution, and cryo–electron microscopy revealed that CorM formed dynamically unstable, antiparallel double-stranded filaments that were recruited to the membrane by CorR through an amphipathic helix conserved in multicellular cyanobacteria. CorMR filaments were regulated by MinC, which excluded them from the poles and division plane. Comparative genomics indicated that the repurposing of ParMR and Min systems coevolved with cyanobacterial multicellularity, highlighting the evolutionary plasticity of cytoskeletal systems in bacteria.
DOI: aea6343
Source: https://www.science.org/doi/10.1126/science.aea6343