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Deficiency of the Arabidopsis Helicase RTEL1 Triggers a SOG1-Dependent Replication Checkpoint in Response to DNA Cross-Links.
- Source :
- Plant Cell; Jan2015, Vol. 27 Issue 1, p149-161, 13p
- Publication Year :
- 2015
-
Abstract
- To maintain genome integrity, DNA replication is executed and regulated by a complex molecular network of numerous proteins, including helicases and cell cycle checkpoint regulators. Through a systematic screening for putative replication mutants, we identified an Arabidopsis thaliana homolog of human Regulator of Telomere Length 1 (RTEL1), which functions in DNA replication, DNA repair, and recombination. RTEL1 deficiency retards plant growth, a phenotype including a prolonged S-phase duration and decreased cell proliferation. Genetic analysis revealed that rtel1 mutant plants show activated cell cycle checkpoints, specific sensitivity to DNA cross-linking agents, and increased homologous recombination, but a lack of progressive shortening of telomeres, indicating that RTEL1 functions have only been partially conserved between mammals and plants. Surprisingly, RTEL1 deficiency induces tolerance to the deoxynucleotide-depleting drug hydroxyurea, which could be mimicked by DNA cross-linking agents. This resistance does not rely on the essential replication checkpoint regulator WEE1 but could be blocked by a mutation in the SOG1 transcription factor. Taken together, our data indicate that RTEL1 is required for DNA replication and that its deficiency activates a SOG1-dependent replication checkpoint. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 10404651
- Volume :
- 27
- Issue :
- 1
- Database :
- Complementary Index
- Journal :
- Plant Cell
- Publication Type :
- Academic Journal
- Accession number :
- 158018090
- Full Text :
- https://doi.org/10.1105/tpc.114.134312