INVESTIGATORS: E.P. Beers, A.M. Brunner, A.W. Dickerman
INSTITUTION: Virginia Tech
NON-TECHNICAL SUMMARY: Proteins are molecular machines that are required for nearly all biological functions. To function, proteins must interact with other molecules such as carbohydrates, lipids, nucleic acids and other proteins. Very little is known about the protein-protein interactions that plant cells use to control cell wall related biomass production. The identification of protein-protein interaction networks associated with biomass production in the woody tissues of poplar, a model biomass crop, will lead to a more detailed understanding of the molecular biology and genomics of plant biomass production and ultimately contribute to strategies for biomass crop improvement.
OBJECTIVE: The objective of the proposal is to map protein-protein interactions relevant to biomass production by focusing on proteins expressed in poplar wood, the site of the majority of secondary cell wall synthesis and hence biomass accumulation in poplar.
APPROACH: We have identified approximately 250 poplar genes specifically associated with wood formation, and have designated these as the poplar biomass gene set. Each of these genes will be cloned and expressed as protein in a yeast expression system known as the yeast two-hybrid system for protein-protein interaction. In the yeast two-hybrid system, individual proteins can be tested for their ability to interact with other proteins expressed in the same yeast cell. We will perform a 250 x 250 yeast two-hybrid matrix assay that will identify interactions occurring between any two members of the poplar biomass protein set. Selected members of the biomass protein set will also be tested in the yeast two-hybridsystem for their ability to interact with any protein found in a library of proteins derived from all the genes expressed in poplar wood-forming tissues. Finally, a small number of biomass proteins will be expressed in plants and tested for their ability to form complexes with other proteins present in woody tissue. Members of protein complexes isolated from plants will be identified using mass spectrometry. All of the interactions revealed as a result of the three types of protein-protein interaction studies will be combined to produce a biomass protein-protein interaction map to aid in the comprehensive understanding of how protein-protein interactions contribute to biomass production by plants.
Name: E.P. Beers