Abstract
Brassica napus leaf protoplasts become swollen and finally degrade, during culture. Both morphological and biochemical approaches revealed that the process through which the death occurred were subjected to apoptotic-like manner. The present results showed that lipid peroxides released into the enzyme solution during the isolation of protoplast, but hydrogen peroxide did not. Greater levels of hydrogen peroxides were accumulated in chloroplasts, while nitrogen oxide (NO) generated in cytoplasm. Mitochondrion did not accumulate hydrogen peroxides. Activation of endonucleases was paralleled with decrease in mitochondria membrane potential. Endnucleases extracted form 2 days after culture were activated by Ca, Mg, Mn, but inhibited by Zn. A endnuclease that were involved in the induction of apoptotic cell death of Brassica napus leaf protoplasts was identified by the active gel staining.
