Reactive oxygen species, nitric oxide and plant cell death associated with caspase-like protease activity during somatic embryogenesis in Fraxinus mandshurica

Abstract Programmed cell death occurs in browning explants of Fraxinus mandshurica during somatic embryogenesis, but the underlying mechanism is unclear. In this study, single cotyledons zygotic embryos F. were used as explants. Mitochondrial structure and function, caspase-3-like protease activity, hydrogen peroxide metabolism, nitric oxide accumulation induced by high concentrations sucrose plant growth regulators studied. The results show that embryogenesis also promoted explant browning. High had similar effects. led to which changes mitochondrial function such modifications morphology, increased membrane permeability, decreased potential, release cytochrome c into cytoplasm. An increase activity triggered programmed some cells. During there activities superoxide dismutase, peroxidase, catalase, are associated with metabolism jointly maintain reactive oxygen species levels. Intracellular synthase nitrate reductase not significantly correlated content. Instead, intracellular may be derived from non-enzymatic reactions. Our indicate signals, playing key roles cells . interaction between determines occurrence cells; positively regulated peroxide. However, regulation complex.