Artificial Sweetener? A Functional Genomics Interrogation of the Impact of Soluble Carbohydrate Metabolism on Poplar Cell Wall Biosynthesis

点击翻译按钮获取中文摘要

Long-lived organisms, such as trees, offer a unique system to investigate how plants allocate carbon, as their perennial nature permits an interrogation of the complex responses to variations in environmental cues while avoiding the dilution of phenotypic responses that arise from genetic segregation common to annual plants. Trees, like all plants, possess an inherent plasticity in their ability to allocate carbon, which is pivitol to the effective modulation of growth and development. Ultimately, resource allocation is controlled by gene expression, which translates into the accumulation of a variety of soluble metabolites, including carbohydrates and phenolics. The resulting chemistry defines the physiology and, importantly, impacts plant form, function and fitness. The long-term objectives of the Mansfield research program, is to understand the complex fundamental processes of carbon allocation in Populus, with a specific emphasis on the intricacies of the biosynthetic processes governing soluble carbohydrate metabolism and how these metabolites contribute to cell wall development. This information is pivotal to understanding programmed cellular growth patterns, and the complex network and regulatory frameworks fundamental to carbon translocation from source tissues to sink tissues, where wood development is a substantial terminal product. The proposed research builds on the previous NSERC Discovery Grants in the Mansfield lab as a foundation to test hypotheses related to the breadth of molecular interactions that shape plant carbon allocation in Populus. Specifically, the proposed research program comprises a body of experiments aimed to address the following objectives: 1) elucidate the nature of the translocatable photoassimilate in Populus; 2) track the fate of carbon supplying the developing xylem of Populus, and 3) dissect the interplay between sucrose synthesis, fructose recycling, and carbohydrate signaling in Populus sink tissue. A greater understanding of the molecular controls that underpin resource allocation in trees could also facilitate strategies aimed at selecting, breeding, and/or engineering trees that maximize resource allocation and strategically direct carbon to vegetative biomass.