Widespread inter‐individual gene expression variability in Arabidopsis thaliana

Abstract

A fundamental question in biology is how gene expression is regulated to give rise to a phenotype. However, transcriptional variability is rarely considered although it could influence the relationship between genotype and phenotype. It is known in unicellular organisms that gene expression is often noisy rather than uniform, and this has been proposed to be beneficial when environmental conditions are unpredictable. However, little is known about inter‐individual transcriptional variability in multicellular organisms. Using transcriptomic approaches, we analysed gene expression variability between individual Arabidopsis thaliana plants growing in identical conditions over a 24‐h time course. We identified hundreds of genes that exhibit high inter‐individual variability and found that many are involved in environmental responses, with different classes of genes variable between the day and night. We also identified factors that might facilitate gene expression variability, such as gene length, the number of transcription factors regulating the genes and the chromatin environment. These results shed new light on the impact of transcriptional variability in gene expression regulation in plants.

Identification and expression analysis of S-alk(en)yl-L-cysteine sulfoxide lyase isoform genes and determination of allicin contents in Allium species

“…To eliminate the environmental effects, the plants were propagated under the same conditions. Eliminating environmental effects via plant propagation under the same conditions have been noted by others studies [42,52,56]. In the current study, the presence of three different isoforms in the Allium was discovered for the first time.…”

Coordinated circadian timing through the integration of local inputs in Arabidopsis thaliana

“…For plants, being responsive to the environment whilst being robust to fluctuations necessitates a trade-off. These fluctuations could be external, such as an environmental change, or internal, such as gene expression noise [75,76]. The clock, in its role as master regulator, must balance the competing requirements of flexibility and robustness.…”

Intracellular Energy Variability Modulates Cellular Decision-Making Capacity

“…Genetically identical single cells in a population choose different phenotypic strategies for survival; genetically identical cells in developing multicellular organisms make decisions to follow different developmental pathways, and hence towards one of a diverse range of possible phenotypes. Across organisms, gene expression variability leads to cell-to-cell variations in mRNA and protein levels in genetically identical cells, and can drive the generation of diverse phenotypes and strategies for survival 1–5 . The process of a cell assuming different functionally important fates from a range of phenotypic possibilities in response to or in anticipation of extracellular change, without genetic modifications, is known as a cellular decision 6 .…”