Poster: Vegetative Development

Abs # 444: Characterization of senescence-activated cysteine protease gene expression in Anthurium and application of methods to reduce leaf and flower senescence

Presenter:	Hayden, Daniel M, hayden@hawaii.edu
Authors	Hayden, Daniel M (A)   Perez, Pierriden A (A)   Christopher, David A (A)
Affiliations:	(A): University of Hawaii @ Manoa

The anthurium flower has long been an important ornamental for Hawaii. The flower consists of the colorful spathe, which actually is a modified leaf, while the central protruding spadix holds hundreds of minute ‘true’ flowers. Molecular approaches are being undertaken to inhibit senescence in leaves and flowers. The ability of cytokinins to repress senescence has been shown in a number of systems, including anthurium. Therefore, we have focused on the autoregulatory senescence inhibition system that involves a senescence-activated promoter (Pr_SAG12) fused to the gene for cytokinin biosynthesis (ipt). We have previously shown that the Arabidopsis Pr_SAG12-GFP was activated in a senescence-dependent manner in anthurium leaves. Similarly, a senescence-activated gene encoding a cysteine protease, anth17, was also isolated and shown to be repressed by benzyladenine treatment. These results indicate the existence of a homologous senescence-activated pathway in this plant. Agrobacterium-mediated transformation using the Pr_SAG12-ipt construct is being carried out. Efforts are also underway to isolate the anth17 gene promoter to develop a Pr_anth17-ipt gene construct. It would be interesting to compare the effect of the different senescence-regulated promoters on the control of senescence. Possible outcomes of this research include prolonging photosynthesis in leaves and increasing production and vase life of flowers.