Genetic editing of wood to improve its qualities and sustainability

Despite the importance of wood fibers in meeting the growing demand for renewable fabrics, paper, packaging, textiles, and other fiber products, wood fiber production is turning out to be less efficient and productive than many scientists would have expected.

Now, the CRISPR gene-editing technique has allowed the team of Daniel B. Sulis, from North Carolina State University in the United States, to engineer wood in which the lignin (which must be cleaved and dissolved for fiber production to take place) is much more suitable than before for fiber production.

“Edited wood alleviates a major bottleneck in fiber production…and could bring unprecedented operational efficiencies, bioeconomic opportunities, and environmental benefits,” the study authors state.

The ability to isolate wood fibers is largely determined by the content and composition of lignin, a recalcitrant biopolymer to chemical and enzymatic degradation.

The individual components of lignin biosynthesis have been extensively examined through more than five decades of research. However, these efforts have predominantly focused on the modification of individual genes or families of genes.

In the new study, Sulis and colleagues show that strategically well-focused gene editing using CRISPR multiplexing of monolignol biosynthesis genes improves wood properties beyond what is achievable by editing individual genes or gene families.

Conventional raw wood: sawn tree trunks. (Photo: NPS/Jay Elhard)

The study authors used their approach to generate a modified wood composition in a poplar species, in which CRISPR editing increased the ratio of wood carbohydrates to lignin by up to 228 percent over the wild type, setting the stage for higher efficiency in obtaining fiber pulp.

Also, trees engineered to have less lignin could make paper production less polluting.

The study is titled “Multiplex CRISPR editing of wood for sustainable fiber production”, and has been published in the academic journal Science. (Source: AAAS)