Arabidopsis COPPER MODIFIED RESISTANCE1/PATRONUS1 is essential for growth adaptation to stress and required for mitotic onset control.
The mitotic checkpoint (MC) guards faithful sister chromatid segregation by monitoring the attachment of spindle microtubules to the kinetochores. When chromosome attachment errors are detected, MC delays the metaphase-to-anaphase transition through the inhibition of the anaphase-promoting complex/cyclosome (APC/C) ubiquitin ligase. In contrast to yeast and mammals, our knowledge on the proteins involved in MC in plants is scarce. Transient synchronization of root tips as well as promoter-reporter gene fusions were performed to analyze temporal and spatial expression of COPPER MODIFIED RESISTANCE1/PATRONUS1 (CMR1/PANS1) in developing Arabidopsis thaliana seedlings. Functional analysis of the gene was carried out, including CYCB1;2 stability in CMR1/PANS1 knockout and overexpressor background as well as metaphase-anaphase chromosome status. CMR1/PANS1 is transcriptionally active during M phase. Its deficiency provokes premature cell cycle exit and in consequence a rapid consumption of the number of meristematic cells in particular under stress conditions that are known to affect spindle microtubules. Root growth impairment is correlated with a failure to delay the onset of anaphase, resulting in anaphase bridges and chromosome missegregation. CMR1/PANS1 overexpression stabilizes the mitotic CYCB1;2 protein. Likely, CMR1/PANS1 coordinates mitotic cell cycle progression by acting as an APC/C inhibitor and plays a key role in growth adaptation to stress.
Laboratory of Plant Physiology and Molecular Genetics, Université Libre de Bruxelles, B-1050, Brussels, Belgium.
Michal
M
Juraniec
Department of Plant Systems Biology, Vlaams Instituut voor Biotechnologie, B-9052, Gent, Belgium.|Department of Plant Biotechnology and Bioinformatics, Ghent University, B-9052, Gent, Belgium.
Jefri
J
Heyman
Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, D-06466, Stadt Seeland, Germany.
Veit
V
Schubert
Laboratory of Plant Physiology and Molecular Genetics, Université Libre de Bruxelles, B-1050, Brussels, Belgium.
Pietrino
P
Salis
Department of Plant Systems Biology, Vlaams Instituut voor Biotechnologie, B-9052, Gent, Belgium.|Department of Plant Biotechnology and Bioinformatics, Ghent University, B-9052, Gent, Belgium.
Lieven
L
De Veylder
Laboratory of Plant Physiology and Molecular Genetics, Université Libre de Bruxelles, B-1050, Brussels, Belgium.
Nathalie
N
Verbruggen
D000222:Adaptation, Physiological; D000705:Anaphase; D064173:Anaphase-Promoting Complex-Cyclosome / Q000378:metabolism; D017360:Arabidopsis / Q000166:cytology / Q000235:genetics* / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D002455:Cell Division; D002869:Chromosome Aberrations; D003300:Copper / Q000378:metabolism; D055786:Gene Knockout Techniques; D017930:Genes, Reporter; D018386:Kinetochores; D018519:Meristem / Q000166:cytology / Q000235:genetics / Q000502:physiology; D008677:Metaphase; D008938:Mitosis; D009154:Mutation; D010641:Phenotype; D018517:Plant Roots / Q000166:cytology / Q000235:genetics / Q000502:physiology; D013312:Stress, Physiological
D029681:Arabidopsis Proteins; D018797:Cell Cycle Proteins; C000589331:patronus protein, Arabidopsis; D003300:Copper; D064173:Anaphase-Promoting Complex-Cyclosome
Arabidopsis thaliana; anaphase onset; anaphase-promoting complex/cyclosome (APC/C); cell cycle; mitotic checkpoint; root apical meristem; stress