Molecular mechanisms governing differential robustness of development and environmental responses in plants

Abstract

This paper reviews recently identified mechanisms, both systems-level and molecular, that modulate robustness, and discusses their implications for the optimization of plant fitness. Robustness in living systems arises from the structure of genetic networks, the specific molecular functions of the underlying genes, and their interactions. This very same network responsible for the robustness of specific developmental states also has to be built such that it enables plastic yet robust shifts in response to environmental changes. In plants, the interactions and functions of signal transduction pathways activated by phytohormones and the tendency for plants to tolerate whole-genome duplications, tandem gene duplication and hybridization are emerging as major regulators of robustness in development. Despite their obvious implications for plant evolution and plant breeding, the mechanistic underpinnings by which plants modulate precise levels of robustness, plasticity and evolvability in networks controlling different phenotypes are under-studied.

Plastic Transcriptomes Stabilize Immunity to Pathogen Diversity: The Jasmonic Acid and Salicylic Acid Networks within the Arabidopsis/Botrytis Pathosystem

“…One possibility is that the defense signaling pathways help the plant to canalize its defense response across a broad array of pathogen genetic diversity. In this context, we define canalization as production by the plant host of a narrow range of phenotypes when confronted with a wide range of pathogen diversity (Waddington, 1942(Waddington, , 1959Queitsch et al, 2002;Lachowiec et al, 2016). Another response to a diverse array of virulence mechanisms could be a plastic response where the range remains the same but the specific response is shifted, or finally, no change in canalization or plasticity.…”

Canalization of Tomato Fruit Metabolism

“…Under specific conditions, trait canalization may be beneficial to the organism, leading to the increase of the allele frequencies contributing to the appearance of the canalized phenotype; on the other hand, there might be cases where the plasticity of a specific trait could confer an adaptive advantage, especially in environments subjected to unpredictable fluctuations (Lachowiec et al, 2016).…”

DnaJ chaperones contribute to canalization

“…Consistent with this hypothesis, an increasing amount of evidence has shown that other molecules are involved in canalization (for more details see reviews by Lachowiec, Queitsch, & Kliebenstein, 2016;Takahashi, 2018). Most of these studies used model organisms that have been kept in a laboratory for many generations.…”