01/01/2013
Proteome Atlas for the Poplar Tree
The Science
Populus, a fast-growing perennial tree, holds potential as a bioenergy crop due to its ability to produce large amounts of biomass on non-agricultural land. For woody perennial plants such as poplar, there is a tight coupling between growth and photosynthesis during the plant’s lifetime. To understand this process, researchers at the U.S. Department of Energy’s BioEnergy Science Center (BESC) have measured more than 11,000 proteins in different tissues of poplar, including mature leaves, young leaves, roots, and stems. They have developed a poplar proteome atlas that shows which proteins are present in the various tissue types at a given point in time. By mapping the proteins back to tissue-specific metabolic pathways, the BESC scientists demonstrated that the same organ can participate in two different growth stages. Their findings confirm prior hypotheses that mature leaves appear to function primarily in the generation of energy via photosynthesis while young leaves partition resources between growth and photosynthesis. This study illustrates that a comprehensive systems approach to proteomics can yield valuable information on the lifecycle of bioenergy-related plants.
Summary
High-performance mass spectrometry (MS)-based proteomics enabled the construction of a detailed proteome atlas for Populus, a woody perennial plant model organism. Optimization of experimental procedures and implementation of current state-of-the-art instrumentation afforded the most detailed look into the predicted proteome space of Populus, offering varying proteome perspectives: (1) network-wide, (2) pathway-specific, and (3) protein-level viewpoints. Experimental validation of the metabolic circuitry expected in mature leaf (characterized by photosynthesis and carbon fixation) compared with young leaf (characterized by rapid growth and moderate photosynthetic activities) strongly testifies to the credibility of the approach.
Principal Investigator
Robert L. Hettich
Oak Ridge National Laboratory
References
Abraham, P., R. J. Giannone, R. M. Adams, U. Kalluri, G. A. Tuskan, and R. L. Hettich. 2013. “Putting the Pieces Together: High-Performance LC-MS/MS Provides Network-, Pathway-, and Protein-Level Perspectives in Populus, “Molecular and Cellular Proteomics 12, 106–119. DOI:10.1074/mcp.M112.022996.