'Redesigned' plants to improve biofuel production

Opening up opportunities to "redesign plants" for efficient biofuel production, researchers have identified the gene regulatory network that controls the formation of xylem -- the major component of wood.

The gene networks that the researchers uncovered control cell wall thickening by the synthesis of the three polymers: cellulose, hemicellulose and lignin.

The three key components, found in plant tissues known as xylem, provide plants with mechanical strength and waterproof cells that transport water.

The authors said the most rigid of the polymers, lignin, represents "a major impediment" to extracting sugars from plant biomass that can be used to make biofuels.

They added that the new genetic advance could act as a map for how future researchers might manipulate the polymer-forming processes to improve the efficiency of biofuel production.

Working in the model plant Arabidopsis thaliana, the team explored how a large number of interconnected transcription factors regulate xylem and cell wall thickening.

"This revealed a highly interconnected network of more than 240 genes and more than 600 protein-DNA interactions that we had not known about before," said Sam Hazen from University of Massachusetts - Amherst.

The study identified hundreds of new regulators and offers considerable insight into the developmental regulation of xylem cell differentiation.

They also found that each cell-wall gene in the xylem regulatory network is bound by an average of five different transcription factors from 35 distinct families of regulatory proteins.

The study appeared in the journal Nature.