Lignin, a major plant constituent, is crucial to the efficient mechanical support and the defense system of plants. The adaptability of plants to changes and stress in their environment in order to survive is due primary to the existence of lignin. For instance, when a plant is forced out of it natural, equilibrium position in space by an environmental compression stress, such as bending, a unique growth pattern involving the formation of a high amount and an abnormal type of lignin is initiated to reinforce the cell wall architecture in order to restore the natural, equilibrium orientation of the plant. Collectively, the resultant tissues formed under such a phenomenon is called "compression wood". We have discovered a unique enzyme, 4-hydroxycinnamate: CoA ligase, whose activity is significantly induced in developing tissues of loblolly pine seedlings subjected to compressional stress. We propose a comprehensive study on this unique metabolic response to the compressional stress by first investigating the molecular biology of this particular enzyme. The overall long term project goal is to illuminate the development of compression wood in compressionally stressed loblolly seedlings at the molecular level and establish a model system which can be used to probe the underlying signals triggering the metabolic changes stimulated by compressional stress. The significance of this project is its role as a foundation from which further investigation of how plants perceive and respond to both normal and altered environmental compression signals can be achieved at a gene level.
