A complete understanding of how plants make cellulose, which is the main component of most plant cell walls used in various man-made materials, may have important implications for its use in biofuels. Researchers at Penn State University have identified the process The main steps in this work, as well as the tools used by plant cells to make cellulose, include the delivery of key components to the proteins used to make cellulose. A paper describing this research was published in the Proceedings of the National Academy of Sciences on March 26. .
'Cellulose is the most abundant biopolymer on the planet,' said Associate Professor of Biochemistry and Molecular Biology at Penn State University, the senior author of the paper, Ying Ying. 'It occupies 95% of paper and 90% of cotton, its derivatives Even in ice cream emulsifiers. In the past 10 years, cellulose is also considered to be the main component of biofuels. Understanding how cellulose is synthesized may enable us to optimize its use as a renewable energy source.
Cellulose in many daily commodities is mainly produced by plants. Although cellulose has economic significance, before this study, researchers only had a basic understanding of how plants created this rich source.
'We know that cellulose is synthesized in the cytoplasmic membrane, which surrounds plant cells within a heterogeneous protein complex - a group of different kinds of proteins - called the cellulose synthase complex,' Gu said. 'But we It is not known if other proteins are involved in complexes or how proteins enter the plasma membrane. To answer these questions, we use a combination of methods including cell imaging, functional genetics and proteomics to create a timeline of events, and Identify the major proteins involved in the preparation of cell synthesis.
The researchers found that a protein called cellulose synthase-interacting protein 1 (CSI1) interacts with a cellulose synthase complex before synthesis, and may help to mark sites on the resulting plasma membrane. They also demonstrated that CSI1 interacts with a separate complex called a vesicle complex that participates in the transport of substances to the plasma membrane of various species and a protein called PATROL1. These components may contribute to cellulose synthesis. The enzyme complex rapidly spreads to the outer membrane of the cell before synthesis.
'We know that the cyst complexes are evolutionarily conserved. Their structure in yeast and mammals remains essentially unchanged. We have here confirmed its role in plants. But PATROL1 is a plant-specific protein, It is not the same as anything we see in mammals or yeast. We are confused about what PATROL1 actually does and are happy to continue to investigate its function.
Since CSI1 interacts with many components essential for cellulose synthesis, the research team plans to use it as a tool to further elucidate this important process and its evolution.
'We finally hope to be able to interpret how plant cells we know how to build cellulose, so that it can be decomposed more efficiently for biofuels,' Gu said, 'This will ultimately increase the efficiency of biomass energy production.'
In addition to Gu, the research team also includes Xiaoyu Zhu of the University of California, Riverside, which was funded by the National Science Foundation (1121375). The Institute of Energy and Environment and the Huck Life Sciences Institute provided additional support.
