PT  - JOURNAL ARTICLE
AU  - Valeria Davì
AU  - Hirokazu Tanimoto
AU  - Dmitry Ershov
AU  - Armin Haupt
AU  - Henry De Belly
AU  - Remi Le Borgne
AU  - Etienne Couturier
AU  - Arezki Boudaoud
AU  - Nicolas Minc
TI  - Mechanosensation Dynamically Coordinates Polar Growth and Cell Wall Assembly to Promote Cell Survival
AID  - 10.1101/299008
DP  - 2018 Jan 01
TA  - bioRxiv
PG  - 299008
4099  - http://biorxiv.org/content/early/2018/04/10/299008.short
4100  - http://biorxiv.org/content/early/2018/04/10/299008.full
AB  - How growing cells cope with size expansion while ensuring mechanical integrity is not known. In walled cells, such as those of microbes and plants, growth and viability are both supported by a thin and rigid encasing cell wall (CW). We deciphered the dynamic mechanisms controlling wall surface assembly during cell growth, using a novel sub-resolution microscopy approach to monitor CW thickness in live rod-shaped fission yeast cells. We found that polar cell growth yielded wall thinning, and that thickness negatively influenced growth. Thickness at growing tips exhibited oscillating behavior with thickening phases followed by thinning phases, indicative of a delayed feedback promoting thickness homeostasis. This feedback was mediated by mechanosensing through the cell wall integrity pathway, which probes strain in the wall to adjust synthase localization and activity to surface growth. Mutants defective in thickness homeostasis lysed by rupturing the wall demonstrating its essential role for walled cell survival.