The study, published on the jorunal "Plant Cell", has been conducted by the DNA Enzymology team at the IGM-CNR, led by Dr. Giovanni Maga, together with the laboratory of Plant Molecular Biology of the University of Pavia, coordinated by Prof. Rino Cella. Oxidative stress, arising from either intracellular metabolism or exogenous sources (UV, radiations, pollution, smoking), can alter the chemical nature of DNA, inducing mutations. The group of Dr. Maga has previously published in the journal Nature that two proteins, DNA polymerase lambda and its cofactor PCNA, are essential to counteract these mutagenic effects in human cells. These same proteins are highly conserved in plants, and the collaborative efforts of the biochemistry laboratory of Dr. Maga and the plant molecular biology group of Prof. Cella, demonstrated that, in the model plant Arabidopsis thaliana, the plant DNA polymerase lambda homolog is induced by UV light. Plant DNA polymerase lambda and PCNA then act together to counteract oxidative DNA damage, in an identical manner as observed in human cells. Further to that, the researchers showed that plant and human proteins can be interchangeably used, testifying the high degree of conservation of these two pathways. These studies pave the way for identifying biomolecular markers for environmental stress assessment of crops as well as for genetic manipulation of plants, to increase their oxidative stress tolerance.
Ref.: AAmoroso A, Concia L, Maggio C, Raynaud C, Bergounioux C, Crespan E, Cella R, Maga G. Oxidative DNA damage bypass in Arabidopsis thaliana requires DNA polymerase λ and proliferating cell nuclear antigen 2. Plant Cell. 2011;23(2):806-22. doi: 10.1105/tpc.110.081455
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