TORRES JOSE ROBERTO
Congresos y reuniones científicas
Título:
DNA glycosylase MBD4L modulates chromatin structure in Arabidopsis infected tissues
Lugar:
Glasgow
Reunión:
Congreso; XVIII International Congress on Molecular Plant-Microbe Interactions; 2019
Resumen:
DNA glycosylase MBD4L modulates chromatin structure in Arabidopsis infected tissues
José R Torres1, Silvina Arias1, Florencia Nota1, Carlos I Lescano1, Nicolas M Cecchini2 and Maria Elena Alvarez1,
(1)CIQUIBIC-CONICET, Universidad Nacional de Córdoba, Cordoba, Argentina, (2)CIQUIBIC-CONICET- Universidad
Nacional de Cordoba, Cordoba, Argentina
Abstract Text:
Chromatin structure controls gene expression, transposon silencing and DNA repair, among many other nuclear
processes. Under certain stress conditions, plants exhibit chromatin remodeling apparently due to changes in the
epigenetic marks of the genome. We previously described that Arabidopsis tissues infected with Pseudomonas
syringae pv tomato (Pst) trigger decondensation of chromocenters, demethylation of DNA, and transient activation of
pericentromeric transposons. In addition, other authors showed that the host genome is damaged under such
condition, and that plant defense mechanisms help to maintain DNA integrity. We wondered if DNA glycosylases help
repair DNA and/or remodel chromatin in Pst-infected tissues. To evaluate this we used comet assays to monitor DNA
strand brakes in wild type and mutant plants. Mutants impaired in the DNA glycosylase MBD4L (Methyl Binding
Domain 4-Like) had lower DNA damage than wild type plants. By confocal microscopy we performed a time course
analysis of Pst-induced heterochromatin relaxation and found that this response is reduced in mbd4l plants.
Consistently, MBD4L maintained a nuclear localization in both basal and infection conditions, and its two splicing
variants reached different subnuclear domains under different stress conditions. Thus, our results suggest that
MBD4L mediates genome repair and chromatin remodeling under biotic stress conditions.
José R Torres1, Silvina Arias1, Florencia Nota1, Carlos I Lescano1, Nicolas M Cecchini2 and Maria Elena Alvarez1,
(1)CIQUIBIC-CONICET, Universidad Nacional de Córdoba, Cordoba, Argentina, (2)CIQUIBIC-CONICET- Universidad
Nacional de Cordoba, Cordoba, Argentina
Abstract Text:
Chromatin structure controls gene expression, transposon silencing and DNA repair, among many other nuclear
processes. Under certain stress conditions, plants exhibit chromatin remodeling apparently due to changes in the
epigenetic marks of the genome. We previously described that Arabidopsis tissues infected with Pseudomonas
syringae pv tomato (Pst) trigger decondensation of chromocenters, demethylation of DNA, and transient activation of
pericentromeric transposons. In addition, other authors showed that the host genome is damaged under such
condition, and that plant defense mechanisms help to maintain DNA integrity. We wondered if DNA glycosylases help
repair DNA and/or remodel chromatin in Pst-infected tissues. To evaluate this we used comet assays to monitor DNA
strand brakes in wild type and mutant plants. Mutants impaired in the DNA glycosylase MBD4L (Methyl Binding
Domain 4-Like) had lower DNA damage than wild type plants. By confocal microscopy we performed a time course
analysis of Pst-induced heterochromatin relaxation and found that this response is reduced in mbd4l plants.
Consistently, MBD4L maintained a nuclear localization in both basal and infection conditions, and its two splicing
variants reached different subnuclear domains under different stress conditions. Thus, our results suggest that
MBD4L mediates genome repair and chromatin remodeling under biotic stress conditions.
