Characterization of cell wall composition in Setaria viridis plants after genome editing

• Grant number: 22/04419-5
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: March 01, 2023
• End date: February 29, 2024
• Field of knowledge: Agronomical Sciences - Agronomy
• Principal Investigator: Wagner Rodrigo de Souza
• Grantee: Fernanda de Oliveira Menezes
• Supervisor: Leonardo Dario Gomez
• Host Institution: Centro de Ciências Naturais e Humanas (CCNH). Universidade Federal do ABC (UFABC). Ministério da Educação (Brasil). Santo André , SP, Brazil
• Institution abroad: University of York, England
• Associated to the scholarship: 19/26761-4 - Effects of genetic modifications in grass cell walls on biomass digestibility and abiotic stresses, BP.DR

Abstract

The degradation of lignocellulosic material is very difficult due to its complex structure. The complex network of cross-links in cell walls can inhibit the digestion of cellulose, blocking enzymatic access to the biomass. Hence, the enzymatic and thermochemical treatment is essential for the degradation of lignocellulosic macromolecules into small subunits for further processing, making this process very costly. As the biomass recalcitrance is basically conferred by the cell wall composition, genetic modification of cell wall represents a powerful tool for the reduction of recalcitrance and, consequently, for the viability of the biofuel production process. Currently, there is a vast literature describing different strategies for cell wall modification to increase biomass digestibility. However, these strategies are applied to different species, lacking a proper comparison of different cell wall modifications in the same species, which makes difficult to adopt a rational strategy of genetic modification to increase digestibility. Caffeic acid O-methyltransferase (COMT) and BAHD acyltransferase genes are described as promising candidates for improving biomass digestibility. Thus, the aim of this proposal is analyzing the digestibility of biomass and to characterize in detail the cell wall composition of Setaria viridis plants after using two distinct strategies of cell wall genetic modification: (1) knocking-out the COMT gene, and (2) knocking-out, simultaneously, three BAHD genes, using a CRISPR/Cas9 approach. With this, we intend to contribute to the understanding of plant cell wall architecture, oscillation patterns and their biosynthesis. Such information is valorous to accelerate the development of technologies for cellulosic ethanol production. (AU)