Genome-edited trees for high-performance engineered wood

• Published in: Matter Vol. 7; no. 10; pp. 3658 - 3671
• Main Authors: Liu, Yu, Li, Gen, Mao, Yimin, Gao, Yue, Zhao, Minhua, Brozena, Alexandra, Wang, Derrick, von Keitz, Samuel, Meng, Taotao, Kim, Hoon, Pan, Xuejun, Qi, Yiping, Hu, Liangbing
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 02.10.2024
• Subjects: 4CL1 knockout; chemical-free processing; densified wood; lignin; mechanical strength; poplar; 4CL1 knockout; densified wood; mechanical strength; poplar; MAP 6: Development; chemical-free processing; lignin
• ISSN: 2590-2385; 2590-2385
• DOI: 10.1016/j.matt.2024.07.003

Replacing conventional structural materials with high-performance engineered wood can reduce CO2 emissions and enhance carbon sequestration. Traditional methods involve energy-intensive chemical treatments to reduce lignin content, resulting in denser, mechanically superior wood but raising sustainability concerns. This work introduces a genome-editing approach to reduce lignin in trees, enabling chemical-free processing of advanced engineered wood. Using the cytosine base editor nCas9-A3A/Y130F, the 4CL1 gene in poplar wood was targeted, achieving a 12.8% lignin reduction. This facilitated waste-free densified wood production through water immersion and hot pressing, yielding a tensile strength of 313.6 ± 6.4 MPa, comparable to aluminum alloy 6061. The strength of densified 4CL1 knockout wood closely matched that of traditionally treated wood (320.2 ± 3.5 MPa), demonstrating the effectiveness of genetic modification in creating sustainable, high-performance engineered wood and contributing to reduced CO2 emissions and environmental conservation. [Display omitted] •Reducing the lignin in polar wood by knocking out the 4CL1 gene•Demonstrating a chemical-free method for processing advanced engineered wood•Densified 4CL1 knockout wood is as strong as densified wood from chemical treatment We demonstrated a waste-free process for processing engineered wood by reducing the lignin content of poplar wood through 4CL1 knockout technology. The 4CL1 knockout wood shows a 12.8% reduction in lignin content without significant growth changes. By soaking this wood in water and hot pressing, we achieved a tensile strength of 313.6 ± 6.4 MPa, 5.6 times higher than that of natural 4CL1 knockout wood and 1.6 times higher than that of densified wild-type wood. This strength is comparable to chemically treated densified wood (320.2 ± 3.5 MPa). Our method eliminates chemical delignification, offering a cost-effective, eco-friendly alternative for producing densified wood. This success highlights genome editing’s potential to create other engineered wood materials with enhanced properties, contributing to a CO2-negative bioeconomy by providing renewable alternatives to traditional materials. Conventional delignification uses chemicals that consume a lot of energy and create significant waste, posing sustainability issues. By using genome-edited poplar trees with lower lignin content, we can skip the chemical delignification process. This innovative approach reduces environmental impact and offers a more sustainable solution for processing engineered wood.