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Glutamate receptors in plants.

ABSTRACT: Ionotropic glutamate receptors function in animals as glutamate-gated non-selective cation channels. Numerous glutamate receptor-like (GLR) genes have been identified in plant genomes, and plant GLRs are predicted, on the basis of sequence homology, to retain ligand-binding and ion channel activity. Non-selective cation channels are ubiquitous in plant membranes and may function in nutrient uptake, signalling and intra-plant transport. However, there is little evidence for amino acid gating of plant ion channels. Recent evidence suggests that plant GLRs do encode non-selective cation channels, but that these channels are not gated by amino acids. The functional properties of these proteins and their roles in plant physiology remain a mystery. The problems surrounding characterization and assignation of function to plant GLRs are discussed in this Botanical Briefing, and potential roles for GLR proteins as non-selective cation channels involved in metabolic signalling are described.

SUBMITTER: Davenport R

PROVIDER: S-EPMC4240445 | biostudies-literature | 2002 Nov

REPOSITORIES: biostudies-literature

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Glutamate receptors in plants.

Davenport Romola R

Annals of botany 20021101 5

Ionotropic glutamate receptors function in animals as glutamate-gated non-selective cation channels. Numerous glutamate receptor-like (GLR) genes have been identified in plant genomes, and plant GLRs are predicted, on the basis of sequence homology, to retain ligand-binding and ion channel activity. Non-selective cation channels are ubiquitous in plant membranes and may function in nutrient uptake, signalling and intra-plant transport. However, there is little evidence for amino acid gating of p ...[more]

PMID: 12466095

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