Study Deciphers Hormone Transport in Plants

A new study conducted by a research team at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory has identified hormone distribution mechanisms in plants that could lead to sustainable bioenergy crops with increased growth and reduced need for fertilizer.

Led by biochemist Chang-Jun Liu, the study identified the protein essential for relocating cytokinins from roots to shoots. Cytokinins are plant hormones that stimulate plant development. Using Arabidopsis, the researchers studied a large family of transport proteins called ATP-binding cassette (ABC) transporters, which act as a kind of inter- or intra-cellular pump moving substances in or out of a plant's cells or their organelles. While performing gene expression analysis on a set of these ABC transporters, the research team found that the gene AtABCG14 is highly expressed in the vascular tissues of roots. They then examined mutant plants with disrupted AtABCG14 gene, and found that without the gene, plants had weaker growth, slenderer stems, and shorter primary roots than their wild-type counterparts. These structural changes are symptoms of cytokinin deficiencies.

According to Liu, manipulating cytokinin distribution by tailoring the action of the transporter protein could be one way to increase biomass yield and stress tolerance of plants grown for biofuels or agriculture.

For more details about this research, read the news release available at: http://www.bnl.gov/newsroom/news.php?a=11608.