Farage-Barhom, S., Department of Postharvest Science of Fresh Produce, Volcani Center, Agricultural Research Organization, Bet Dagan, 50250, Israel, Faculty of Life Science, Bar Ilan University, Ramat Gan, Israel
Burd, S., Department of Postharvest Science of Fresh Produce, Volcani Center, Agricultural Research Organization, Bet Dagan, 50250, Israel
Sonego, L., Department of Postharvest Science of Fresh Produce, Volcani Center, Agricultural Research Organization, Bet Dagan, 50250, Israel
Mett, A., Department of Vegetable Research, Volcani Center, Agricultural Research Organization, Bet Dagan, 50250, Israel
Belausov, E., Department of Ornamental Horticulture, Volcani Center, Agricultural Research Organization, Bet Dagan, 50250, Israel
Gidoni, D., Department of Vegetable Research, Volcani Center, Agricultural Research Organization, Bet Dagan, 50250, Israel
Lers, A., Department of Postharvest Science of Fresh Produce, Volcani Center, Agricultural Research Organization, Bet Dagan, 50250, Israel

Plant senescence-or PCD-associated nucleases share significant homology with nucleases from different organisms. However, knowledge of their function is limited. Intracellular localization of the Arabidopsis senescence-and PCD-associated nuclease BFN1 was investigated. Analysis of BFN1-GFP localization in transiently transformed tobacco protoplasts revealed initial localization in filamentous structures spread throughout the cytoplasm, which then clustered around the nuclei as the protoplasts senesced. These filamentous structures were identified as being of ER origin. In BFN1-GFP-transgenic Arabidopsis plants, similar localization of BFN1-GFP was observed in young leaves, that is, in filamentous structures that reorganized around the nuclei only in senescing cells. In late senescence, BFN1-GFP was localized with fragmented nuclei in membrane-wrapped vesicles. BFN1's postulated function as a nucleic acid-degrading enzyme in senescence and PCD is supported by its localization pattern. Our results suggest the existence of a dedicated compartment mediating nucleic acid degradation in senescence and PCD processes. © The Author 2011. Published by the Molecular Plant Shanghai Editorial Office in association with Oxford University Press on behalf of CSPB and IPPE, SIBS, CAS.