DELLA and EDS1 Form a Feedback Regulatory Module to Fine-Tune Plant Growth–Defense Tradeoff in Arabidopsis

Abstract

Plants maintain a dynamic balance between growth and defense , and optimize allocation of resources for survival under constant pathogen infections. However, the underlying molecular regulatory mechanisms, especially in response to biotrophic bacterial infection, remain elusive. Here, we demonstrate that DELLA proteins and EDS1, an essential resistance regulator, form a central module modulating plant growth-defense tradeoffs via direct interaction. When infected by Pst DC3000, EDS1 rapidly promotes salicylic acid (SA) biosynthesis and resistance-related gene expression to prime defense response, while pathogen infection stabilizes DELLA proteins RGA and RGL3 to restrict growth in a partially EDS1-dependent manner, which facilitates plants to develop resistance to pathogens. However, the increasingly accumulated DELLAs interact with EDS1 to suppress SA overproduction and excessive resistance response. Taken together, our findings reveal a DELLA-EDS1-mediated feedback regulatory loop by which plants maintain the subtle balance between growth and defense to avoid excessive growth or defense in response to constant biotrophic pathogen attack.

Genome-wide Analysis and Functional Characterization of the Della Gene Family Associated With Stress Tolerance in B. Napus

“…AtRGL1 and AtRGL2 are involved in modulating leaf senescence, male sterility, and seed germination [23,24]. While AtRGL3 has been reported to contribute plant defense in response to biotic stresses [10,26,71]. Consistent with this, our qRT-PCR and predicted RNA-Seq data (Table S4.1) indicated that the individual BnDELLA gene subfamily exhibits signi cant varied expression and response to biotic and abiotic stress.…”

“…In recent years, the cultivation of the B. napus declining due to the versatility of the environment. DELLAs are well known as the master negative coregulators to mediate cross-talk between GAs and multiple hormonal signals to modulate plant growth and survival tradeoff, responding to abiotic and biotic conditions [8,10]. Previous reports on seeded plants had identi ed 1, 2, and 5 DELLA genes in Oryza sativa [16], Pisum sativum [18], and A. thaliana, respectively.…”

“…Among these hormones, Gibberellins (GAs) are considered one of the most vital hormones that dramatically affect plant physiology by cross-talking with multiple hormones [7,8]. However, under external pressure, plants maintain GAs homeostasis by a family of coregulator DELLAs, which interact with a wide variety of transcriptional factors and transcriptional regulators of multiple hormones, to inhibit growth in allocating resources for plant survival [9,10]. Previously, it proposed that mutation in 17 amino acids of the DELLA N-terminal region resulted in severe dwarf transgenic plant gai-1 with dark green leaves, much like GA-de cient mutant ga1-3 [11,12].…”

“…For instance, AtGAI and AtRGA have been denoted as notable repressors of the plant vegetative growth [9,20,21], whereas AtRGL1 and AtRGL2, respectively, are involved in repressing oral augmentation and seed germination [22][23][24][25]. AtRGL3 was recently got attention in plant defense by positively regulating the JA and SA mediated response against pathogen infections [10,26].…”

Virus‐induced phytohormone dynamics and their effects on plant–insect interactions

“…Finally, rice black‐streaked dwarf virus regulates the GA‐signaling pathway via the interaction of the virus‐encoded P7‐2 and the plant’s GA‐insensitive dwarf2 (GID2) protein, which is an important component of GA signaling that dictates the degradation of DELLA proteins (Tao et al ., 2017). DELLAs are critical regulatory proteins that help to mediate crosstalk of GA with the JA‐ and SA‐signaling pathways, which is essential for balancing growth and defense (Navarro et al ., 2008; Y. Li et al ., 2019).…”