Effect of photodestruction of plastids from norflurazon-treated barley seedlings on expression of nuclear genes encoding chloroplast stress proteins

The effects of photodestruction of chloroplasts in norflurazon-treated barley seedlings on expression of nuclear genes Elip and Hsp32 encoding light and heat stress proteins of barley chloroplasts and also of the Lhcb1 and RbcS genes of photosynthesis proteins were studied. The genes of the photosynthesis proteins were not transcribed upon the photodestruction of chloroplasts. However, transcription of the stress protein genes continued, and the transcription of the heat stress protein gene remained virtually at the control level, whereas the light stress protein gene transcription was markedly (by 30-50%) decreased, and this suggests chloroplast control of the Elip gene transcription. Disorders in the processing and a partial disturbance in the import of precursors of Hsp32 and Elip proteins into the plastids of the norflurazon-treated seedlings were shown. Data on protease analysis indicates that photodestruction of chloroplasts is associated with accumulation of stress protein precursors in the plastid envelope.