Ethylene biosynthetic genes in 'Moso' bamboo shoot in response to wounding

Bamboo shoots are immature, expanding culms that emerge from nodes of the rhizome of bamboo (Phyllostachys edulis) plants. The edible part consists of meristematic tissues with regions of rapid cell division and differentiation, which is enveloped in protective, non-edible leaf sheaths. However, unlike other perishable vegetables harvested bamboo shoots produce a large amount of ethylene in response to wounding. To investigate ethylene induction mechanisms in wounded bamboo shoots, we cloned cDNAs encoding 1-aminocyclopropane-1-carboxylic acid (ACC) synthase (pBA-ACS) and ACC oxidase (pBA-ACO) genes involved in ethylene biosynthesis, and we analyzed their expression in wounded tissue after harvest. Ethylene production was induced within 8 h of wounding accompanied by increased enzyme activity and increased mRNA accumulation of pBA-ACS and pBA-ACO. On the other hand, treatment with 1-methylcyclopropene, an inhibitor of ethylene action, suppressed ethylene production and ethylene biosynthesis-related gene expression.