Study Shows How Plants Sort and Eliminate Genes Over Millenia

Plants with multiple genomes tend to prefer the genes from one parent and discard the rest. This was recently reported by Brian Dilkes, an assistant professor of Genetics at Purdue University in a study published in the journal Genome Biology.

The genome of hybrid Arabidopsis suecica originated from four chromosome sets from crosses between Arabidopsis arenosa and Arabidopsis thaliana tens of thousands of years ago. Similar species of hybrids were developed from fresh crosses in the laboratory. However, researchers found that the contribution of genes from each parent was not equal such that genes from A. arenosa were three times more preferred than the other parent. And genes that are co-expressed in similar tissues are preferentially expressed from the same parent.

"Our findings suggest an additional network dependence, where genes fine-tuned to work together within either parental species prior to hybridization are more likely to be expressed together in the hybrid. This, in turn, ensures that these genes acquired from one parental species are kept together and are not lost in the genome over time," said Peter Chang, a graduate student at University of Southern California and lead author of the paper. "Plants have had a remarkable ability to adapt to different conditions throughout Earth's history, and we are just beginning to understand some of ways this is done."

For more details on this study, see http://www.purdue.edu/newsroom/research/2011/110309DilkesScience.html