Application of T-DNA activation tagging to identify glutamate receptor-like genes that enhance drought tolerance in plants

Abstract

A high-quality rice activation tagging population has been developed and screened for drought-tolerant lines using various water stress assays. One drought-tolerant line activated two rice glutamate receptor-like genes. Transgenic overexpression of the rice glutamate receptor-like genes conferred drought tolerance to rice and Arabidopsis. Rice (Oryza sativa) is a multi-billion dollar crop grown in more than one hundred countries, as well as a useful functional genetic tool for trait discovery. We have developed a population of more than 200,000 activation-tagged rice lines for use in forward genetic screens to identify genes that improve drought tolerance and other traits that improve yield and agronomic productivity. The population has an expected coverage of more than 90 % of rice genes. About 80 % of the lines have a single T-DNA insertion locus and this molecular feature simplifies gene identification. One of the lines identified in our screens, AH01486, exhibits improved drought tolerance. The AH01486 T-DNA locus is located in a region with two glutamate receptor-like genes. Constitutive overexpression of either glutamate receptor-like gene significantly enhances the drought tolerance of rice and Arabidopsis, thus revealing a novel function of this important gene family in plant biology.

Glutamate receptors are involved in mitigating effects of amino acids on seed germination of Arabidopsis thaliana under salt stress

“…Studies with pharmacological and genetic approaches have shown that the plant GLRs participate in the regulation of various physiological and developmental processes, including regulation of abscisic acid biosynthesis, carbon/nitrogen sensing, innate immunity, leaf-to-leaf wound signaling, organelle morphology, pollen growth, coordination of mitotic activity in root meristem, lateral root development, drought and ionic stress, the regulation of root growth and branch, the response to aluminum, light signaling transduction (Kang et al 2004;Kang and Turano 2003;Li et al 2013;Li et al 2006;Lu et al 2014;Manzoor et al 2013;Michard et al 2011;Mousavi et al 2013;Roy et al 2008;Sivaguru et al 2003;Teardo et al 2015;Vatsa et al 2011;Vincill et al 2013). Kong et al (2015) reported that GLRs are involved in the regulation of seed germination by antagonzing ABA.…”

Transcription Factors and microRNA Genes Regulatory Network Construction Under Drought Stress in Sesame (Sesamum indicum L.)

“…Genes such as NIM1-interacting 2-like, glutamate receptor 2.9-like, receptor-like protein, and pathogenesis-related protein 5-like were found down-regulated in the DTR set. Although there have been reports that overexpression some of these genes have a positive effect on tolerance to abiotic stresses [55,56,57], but better-known function of all of them is resistance to disease and biotic stresses [58,59,60,61,62,63]. Based on the results, it seems likely that tolerant genotype at high drought levels downregulate the expression of some of the disease-related genes (not all) and thus spend their stored energy on producing other vital compounds to survive under severe drought stress.…”

Calcium-Mediated Abiotic Stress Signaling in Roots

“…Another possibility is that CNGCs are involved as ABA can increase cGMP levels (Isner et al, 2012.). GLRs are firmly implicated in the drought response; overexpression of rice GLR1 and GLR2 enhances drought tolerance of both rice and Arabidopsis (Lu et al, 2014). The [Ca 2+ ] cyt increase is likely to lead to a transcriptional response as Ca 2+ -sensing proteins are activated.…”