Format

Send to

Choose Destination
Sci Rep. 2017 Jul 21;7(1):6164. doi: 10.1038/s41598-017-06335-4.

Deficient glutamate biosynthesis triggers a concerted upregulation of ribosomal protein genes in Arabidopsis.

Author information

1
Instituto de Bioingeniería, Universidad Miguel Hernández, Campus de Elche, 03202, Elche, Spain.
2
Instituto de Bioingeniería, Universidad Miguel Hernández, Campus de Elche, 03202, Elche, Spain. jlmicol@umh.es.

Abstract

Biomass production requires the coordination between growth and metabolism. In a large-scale screen for mutants affected in leaf morphology, we isolated the orbiculata1 (orb1) mutants, which exhibit a pale green phenotype and reduced growth. The combination of map-based cloning and next-generation sequencing allowed us to establish that ORB1 encodes the GLUTAMATE SYNTHASE 1 (GLU1) enzyme, also known as FERREDOXIN-DEPENDENT GLUTAMINE OXOGLUTARATE AMINOTRANSFERASE 1 (Fd-GOGAT1). We performed an RNA-seq analysis to identify global gene expression changes in the orb1-3 mutant. We found altered expression levels of genes encoding enzymes involved in nitrogen assimilation and amino acid biosynthesis, such as glutamine synthetases, asparagine synthetases and glutamate dehydrogenases, showing that the expression of these genes depends on the levels of glutamine and/or glutamate. In addition, we observed a concerted upregulation of genes encoding subunits of the cytosolic ribosome. A gene ontology (GO) analysis of the differentially expressed genes between Ler and orb1-3 showed that the most enriched GO terms were 'translation', 'cytosolic ribosome' and 'structural constituent of ribosome'. The upregulation of ribosome-related functions might reflect an attempt to keep protein synthesis at optimal levels even when the pool of glutamate is reduced.

Supplemental Content

Full text links

Icon for Nature Publishing Group Icon for PubMed Central
Loading ...
Support Center