Raghunathan Suchitha, Chimthanawala Afroze, Krishna Sandeep, Vecchiarelli Anthony G, Badrinarayanan Anjana
National Centre for Biological Sciences, Tata Institute of Fundamental Research and.
The University of Trans-Disciplinary Health Sciences and Technology (TDU), Bangalore 560064, India.
Mol Biol Cell. 2020 Dec 15;31(26):2920-2931. doi: 10.1091/mbc.E20-08-0547. Epub 2020 Oct 28.
Faithful propagation of life requires coordination of DNA replication and segregation with cell growth and division. In bacteria, this results in cell size homeostasis and periodicity in replication and division. The situation is perturbed under stress such as DNA damage, which induces filamentation as cell cycle progression is blocked to allow for repair. Mechanisms that release this morphological state for reentry into wild-type growth are unclear. Here we show that damage-induced filaments divide asymmetrically, producing short daughter cells that tend to be devoid of damage and have wild-type size and growth dynamics. The Min-system primarily determines division site location in the filament, with additional regulation of division completion by chromosome segregation. Collectively, we propose that coordination between chromosome (and specifically segregation and cell division may result in asymmetric division in damage-induced filaments and facilitate recovery from a stressed state.
生命的忠实繁衍需要DNA复制和分离与细胞生长及分裂相协调。在细菌中，这导致了细胞大小的稳态以及复制和分裂的周期性。在诸如DNA损伤等应激条件下，这种情况会受到干扰，DNA损伤会诱导细胞形成丝状体，因为细胞周期进程被阻断以进行修复。使这种形态状态得以解除从而重新进入野生型生长的机制尚不清楚。在这里，我们表明，损伤诱导的丝状体进行不对称分裂，产生的短子代细胞往往没有损伤，具有野生型大小和生长动态。Min系统主要决定丝状体中的分裂位点位置，染色体分离对分裂完成有额外调控作用。我们共同提出，染色体之间的协调（特别是分离和细胞分裂）可能导致损伤诱导的丝状体进行不对称分裂，并促进从应激状态中恢复。
