New Method for Identifying Genetic Regulatory Networks in Poplar

The Science

Wood is an important renewable material for bioenergy and other industrial products, but its formation, a complex process regulated at many levels, is poorly understood. Such processes often involve interactions between regulatory genes known as transcription factors (TFs) and their direct DNA targets. These TF-DNA interactions constitute a regulatory hierarchy. To begin to understand these systems in poplar trees, researchers at North Carolina State University funded by the Department of Energy’s Genomic Science Program developed a robust, high-throughput pipeline to study the hierarchy of genetic regulation of wood formation using tissue-specific single cells known as protoplasts. A new method for isolating protoplasts from the wood-forming stem differentiating xylem (SDX) tissues of Populus trichocarpa was developed and used to study the expression of a specific poplar TF affecting wood formation. By integrating this novel system with computational approaches, a hierarchical layer of genes was inferred that was then functionally validated in SDX.

The Impact

This approach will be particularly useful in studying complex processes in plant species that lack mutants and a stable transformation system. It also can be used to improve forest tree productivity with more precise genetic approaches.


Lin, Y.-C., W. Li, Y.-H. Sun, S. Kumari, H. Wei, Q. Li, S. Tunlaya-Anukit, R. R. Sederoff, and V. L. Chiang VL. 2013. “SND1 Transcription Factor-Directed Quantitative Functional Hierarchical Genetic Regulatory Network in Wood Formation in Populus trichocarpa,” Plant Cell 25, 4324-41. DOI:10.1105/tpc.113.117697.