Ionotropic glutamate receptors (iGluRs) are a group of proteins with a high degree of sequence homology. At least 20 type of putative ionotropic glutamate receptor (iGluR)-like channels have been identified in Arabidopsis thaliana. To uncover the role of iGluR-like channels in plant root growth, we used a comprehensive set of compounds known to alter iGluR channels in the neurons. We found that Arabidopsis root system is highly sensitive to these compounds. iGluR competitive antagonists 6-Cyano-7-nitroquinoxaline-2,3-dione (CNQX) or 6,7-dinitroquinoxaline-2,3-dione acted (DNQX) acts as a negative regulator of primary root and lateral root density. Continuous growth on antagonist also leads to impairment of root meristem size, which suggests that iGluR-like channels may play a role in meristem maintenance. However, application of iGluR agonists L-glutamate recovered Arabidopsis root growth. Taken together, these results suggest a correlation between the putative iGluR-like channel function and the alteration of root growth and development in the Arabidopsis roots.
Part of the book: GABA And Glutamate