| Literature DB >> 34618100 |
Thomas Eekhout1,2, Martina Dvorackova3, José Antonio Pedroza Garcia1,2, Martina Nespor Dadejova3, Pooneh Kalhorzadeh1,2, Hilde Van den Daele1,2, Ilse Vercauteren1,2, Jiri Fajkus3, Lieven De Veylder1,2.
Abstract
The WEE1 and ATM AND RAD3-RELATED (ATR) kinases are important regulators of the plant intra-S-phase checkpoint; consequently, WEE1KO and ATRKO roots are hypersensitive to replication-inhibitory drugs. Here, we report on a loss-of-function mutant allele of the FASCIATA1 (FAS1) subunit of the chromatin assembly factor 1 (CAF-1) complex that suppresses the phenotype of WEE1- or ATR-deficient Arabidopsis (Arabidopsis thaliana) plants. We demonstrate that lack of FAS1 activity results in the activation of an ATAXIA TELANGIECTASIA MUTATED (ATM)- and SUPPRESSOR OF GAMMA-RESPONSE 1 (SOG1)-mediated G2/M-arrest that renders the ATR and WEE1 checkpoint regulators redundant. This ATM activation accounts for the telomere erosion and loss of ribosomal DNA that are described for fas1 plants. Knocking out SOG1 in the fas1 wee1 background restores replication stress sensitivity, demonstrating that SOG1 is an important secondary checkpoint regulator in plants that fail to activate the intra-S-phase checkpoint. © American Society of Plant Biologists 2021. All rights reserved. For permissions, please email: journals.permissions@oup.com.Entities:
Mesh：
Substances：
Year: 2021 PMID： 34618100 PMCID： PMC8331141 DOI： 10.1093/plphys/kiab201
Source DB: PubMed Journal: Plant Physiol ISSN： 0032-0889 Impact factor: 8.340