New strigolactone receptor advances knowledge of how germination is induced in parasitic plants

July 31, 2015

RIKEN CSRS and the University of Georgia researchers have found genes for strigolactone receptors that induce germination of parasitic plants. The joint research group compared the genomic sequences of parasitic plants and non-parasitic plants, discovering an increase in the number of genes that code for the KAI2 proteins. Upon analyzing the structure of the KAI2 proteins, researchers determined that part of the KAI2 proteins in parasitic plants are similar to the Arabidopsis thaliana D14 protein, which is a known strigolactone receptor.

This finding suggested that parasitic plants use KAI2 proteins as strigolactone receptors. Upon introducing the a KAI2 protein from a parasitic plant into an Arabidopsis kai2 mutant, the researchers successfully created a plant that germinated in response to strigolactone. It is believed that the KAI2 genes from the parasitic plant evolved independently of the D14 gene in Arabidopsis and acquired strigolactone receptor functionality.

Parasitic plants such as Striga and Orobanche are plant pests that cause agricultural damage worldwide. Understanding the mechanisms of seed germination of parasitic plants should lead to prevention of agricultural damage.


Original article
Science doi: 10.1126/science.aab1140
C. E. Conn, R. Bythell-Douglas, D. Neumann, S. Yoshida, B. Whittington, J. H. Westwood, K. Shirasu, C. S. Bond, K. A. Dyer, D. C. Nelson,
"Convergent evolution of strigolactone perception enabled host detection in parasitic plants".

Ken Shirasu; Group Director
Satoko Yoshida; Senior Research Scientist
Plant Immunity Research Group