Bcl-2Δ21 and Ac-DEVD-CHO Inhibit Death of Wheat Microspores

Microspore cell death and low green plant production efficiency are an integral obstacle in the development of doubled haploid production in wheat. The aim of the current study was to determine the effect of anti-apoptotic recombinant human B-cell lymphoma 2 (Bcl-2 Delta 21) and caspase-3-inhibitor (Ac-DEVD-CHO) in microspore cell death in bread wheat cultivars AC Fielder and AC Andrew. Induction medium containing Bcl-2 Delta 21 and Ac-DEVD-CHO yielded a significantly higher number of viable microspores, embryo-like structures and total green plants in wheat cultivars AC Fielder and AC Andrew. Total peroxidase activity was lower in Bcl-2 Delta 21 treated microspore cultures at 96 h of treatment compared to control and Ac-DEVD-CHO. Electron paramagnetic resonance study of total microspore protein showed a different scavenging activity for Bcl-2 Delta 21 and Ac-DEVD-CHO. Bcl-2 Delta 21 scavenged approximately 50% hydroxyl radical (HO center dot) formed, whereas Ac-DEVD-CHO scavenged approximately 20% of HO center dot. Conversely, reduced caspase-3-like activities were detected in the presence of Bc-2 Delta 21 and Ac-DEVD-CHO, supporting the involvement of Bcl-2 Delta 21 and Ac-DEVD-CHO in increasing microspore viability by reducing oxidative stress and caspase-3-like activity. Our results indicate that Bcl-2 Delta 21 and Ac-DEVD-CHO protects cells from cell death following different pathways. Bcl-2 Delta 21 prevents cell damage by detoxifying HO center dot and suppressing caspase-3-like activity, while Ac-DEVD-CHO inhibits the cell death pathways by modulating caspase-like activity.