Purdue University researchers have found a mechanism that naturally shuts down cellulose production in plants.
Learning how to keep that switch turned on may be key to enhancing biomass production for plant-based biofuels, the Purdue team reported in this week's Proceedings of the National Academy of Sciences (PNAS).
Most biofuel researchers believe that cellulose utilization offers the best path to sustainable ethanol production.
The researchers made the discovery in barley after introducing a virus as a way to "silence" specific genes and study their functions.
"The virus hijacked a whole suite of genes, and when we compared the targeted plant to our control plants we found that the small RNAs were responsible and already in the controls even without adding the virus," said the authors.
According to their findings, small-interfering RNAs (siRNAs) play a normal role in plant development by shutting off genes involved in primary cell wall growth in order to begin development of thicker, secondary cell walls.
These secondary stages result in characteristics such as tough rinds of corn stalks, vascular elements to conduct water and fibers for strength. The researchers said that delaying or preventing the shutdown of both primary and secondary cellulose production might enhance total plant biomass, Xinhua news agency reported.
"If we can learn to interfere with the down-regulation of cellulose synthesis, then plants may be able to produce more cellulose, which is key to biofuels production," said lead researcher Nicholas Carpita.
"Our work uncovered a previously unknown mechanism that suggests a way to increase the amount of cellulose produced in plants," said the authors.