Abstract
To clarify the processes involved in plant immunity, we have isolated and characterized Arabidopsis mutant, nsl2 (necrotic spotted leasion 2), which shows a phenotype that mimics the lesions seen in the hypersensitive response. Inoculation of nsl2 mutant plants with virulence pathogen shows that the nsl2 mutation results in the restriction of bacterial growth (Plant Cell Physiol. 2005, 46: 902-912). Additionally, the nsl2 showed accelerated senescence under dark conditions, suggesting that the NSL2 is associated to chlorophyll degradation. HPLC analysis revealed that the nsl2 mutant accumulates pheophorbide a but not intermediates of chlorophyll synthesis. Moreover, dark treatment leaded to rapid decrease in photosynthetic proteins in the nsl2 mutant . Characters of NSL2-mediated senescence and chlorophyll degradation will be reported.
