North Carolina State University researchers have uncovered how a complex network of transcription factors switch wood formation genes on and off. Understanding this transcriptional regulatory network has applications for modifying wood properties for timber, paper and biofuels, as well as making forest trees more resistant to diseases and pests.
Dr Jack Wang, co-lead author of a paper summarising the work, said: “We’re building a more complete story of how wood formation functions – all the intricate components, their interactions and how they fit together to regulate wood formation inside the cell walls of woody plants.
“A complex network of transcription factors regulate which wood formation genes are turned on or off.
“Understanding this network allows us to identify single switches inside that complex network of transcription factors that could simultaneously control multiple wood-forming genes. Instead of working with one, two or three genes at a time, which is our current limit, plant biologists could work with tens of genes at a time.”
Dr Wang’s team used transgenic black cottonwood (Populus trichocarpa) – a move that was critical to the new findings. A non-woody species, Arabidopsis thaliana, is often used as a model plant in botanical studies. However this new study upended ideas about transcriptional regulatory networks inferred from work with Arabidopsis. The North Carolina study found that the network of transcription factor regulation in woody tissue is almost completely different from the regulatory processes in Arabidopsis and other plants.
Of the 57 regulatory interactions identified, 55 were specific to woody plant tissue, showing that herbaceous plants like Arabidopsis cannot stand in for woody plants in this sort of research.
The goal now is to provide a toolkit for building trees with the specific properties needed for commercial timber, paper, biofuel production and conservation requirements.
Source:
Chen, H., Wang, J.P., Liu, H., Li, H., Lin, Y.C., Shi, R., Yang, C., Gao, J., Zhou, C., Li, Q., Sederoff, R.R., Li, Wei., & Chiang, V.L. (2019). Hierarchical Transcription-Factor and Chromatin Binding Network for Wood Formation in Populus trichocarpa. The Plant Cell.
