The plant hormone auxin triggers an ultra-fast proteome-wide response.

The plant signaling molecule auxin controls growth and development through a simple nuclear pathway that regulates the expression of numerous genes. There are however several cellular and physiological responses to auxin that occur within seconds, far too rapid to be mediated by gene expression changes, for which no molecular mechanism has yet been identified. Using a phosphoproteomic strategy in Arabidopsis thaliana roots, an ultra-rapid auxin response system that targets >2000 proteins of which many within 30 seconds was identified.