Neogen Corporation has developed numerous immunoassays currently in wide commercial practice to detect and quantify toxic residues (e.g. mycotoxins, sulfonamides). Technology is currently being developed for detecting and quantifying the developmentally regulated enzyme 1-aminocyclopropane-l-carboxylate (ACC) oxidase in ethylene biosynthesis in plants, expressed in climacteric fruits as they mature and obligatory for ripening. An ACC oxidase polyclonal antibody-based ELISA was developed by Neogen Corporation for research as a maturity/ripening index for climacteric fruits. We have found that an ethylene-related protein, PApER-1, is expressed in fruits in response to exogenous ethylene just before the expression of ACC oxidase. This protein may regulate the expression of ACC oxidase via a positive feed-back control mechanism. As such, the detection of PApER-1 in fruits would pre-stage the appearance of ACC oxidase and provide a means to alert fruit growers that fruit maturation has been completed and that the onset of ripening is eminent. The specific objective of this proposal is to produce and characterize monoclonal antibodies (MAb) against the PApER-1 antigen. These MAbs will subsequently be used to develop an ELISA to detect and quantify PApER-1 as an index for use alone or in tandem with the ACC oxidase ELISA, the latter assessing status of ripening.
Anticipated Results:The PApER-1 ELISA would have commercial application when used alone or in tandem with the ACC oxidase ELISA as a maturity test kit for a wide range of important fruits of the climacteric class such as apples, pears and tomatoes, which are harvested at the mature but unripe stage of development. Its use may ensure good handling attributes and allow fruits to achieve superior quality when ripened in route through handling, transport, storage and distribution to the ultimate consumer. The ELISA would be useful to fruit growers, handlers, storage operators, extension agents, consultants and fruit researchers. Moreover, the ELISA (and the MAb itself) would be generally useful to biologists researching the role of ethylene in plant biology.
