IBR   13079
INSTITUTO DE BIOLOGIA MOLECULAR Y CELULAR DE ROSARIO
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Deregulation of hydrogen peroxide levels by a CCT-domain containing protein in Arabidopsis
Autor/es:
OSELLA, AV; VALLE EM; ZANOR MI
Reunión:
Congreso; SAIB 2013; 2013
Resumen:
CCT domain-containing proteins are found in a wide range of flowering
plants but not in mammals or yeast. They are considered to function as
transcriptional regulators implicated in diverse processes such as
photoperiodic flowering, regulation of circadian rhythms, light signalling
and gene expression in response to sugars. Here we report the
identification of a CCT domain-containing protein (UKCCT) which is
downregulated upon treatment of Arabidopsis seedlings with the herbicide
Methyl Viologen in light. In this work we analyzed sub cellular and tissue
specific expression using transgenic plants. Arabidopsis plants expressing
the UKCCT-GFP fusion protein showed nuclei localization indicating that
UKCCT function might be related to regulatory processes. Using
promoter-GUS reporter fusions we observed high expression of UKCCT in
shoots, especially in cotyledons and leaves but not in stem and roots.
Interestingly, Arabidopsis plants over-expressing UKCCT show a
deregulation of H2O2 and O2- levels, chlorotic and hyponastic leaves
resembling the phenotype observed in cat2 mutants. Moreover, plants
over-expressing UKCCT show a lesser photosynthetic efficiency and a lower
seed production than WT and ukcct mutant . Our working hypothesis is that
the function of this protein is related to the regulation of hydrogen
peroxide levels leading to lesions formation.