Characterization of effects of over-expression of the MADS domain factor AGL15 on plant development

AGL15 (AGAMOUS-Like 15) is a member of the MADS domain family of regulatory factors. Although AGL15 is preferentially expressed during embryogenesis, the fact that AGL15 expression is associated with leaf primordia, vegetative apical meristems and floral buds (Fernandez et. al., Plant Cell, Vol. 12,183–197) suggests that AGL15 may play a role during post-germinative development as well. Moreover, transgenic plants that constitutively express AGL15 show delayed abscission and senescence of perianth organs.; The goal of my research is to enhance our understanding of the effect that ectopic AGL15 has on reproductive development. I approached this by monitoring effects on floral organ abscission, floral organ senescence, and fruit development processes using molecular markers as well as physiological features. I also investigated the developmental context in which AGL15 exerts its effect on senescence and abscission processes of reproductive organs by generating transgenic plants with regulated expression of AGL15. The effects of tissue-specific expression (floral organ abscission zone specific expression), senescence-activated expression of AGL15 and two component glucocorticoid-inducible expression were examined. The molecular aspects of global gene regulation in plants over-expressing AGL15 were also examined using microarray analysis.