SPL9 mediates freezing tolerance by directly regulating the expression of CBF2 in Arabidopsis thaliana

Abstract

Background Freezing stress inhibits plant development and causes significant damage to plants. Plants therefore have evolved a large amount of sophisticated mechanisms to counteract freezing stress by adjusting their growth and development correspondingly. Plant ontogenetic defense against drought, high salt, and heat stresses, has been extensively studied. However, whether the freezing tolerance is associated with ontogenetic development and how the freezing signals are delivered remain unclear. Results In this study, we found that the freezing tolerance was increased with plant age at the vegetative stage. The expressions of microRNA156 (miR156) and SQUAMOSA PROMOTER BINDING PROTEIN-LIKE 9 (SPL9), playing roles in regulation of ontogenetic development, were induced by cold stress. Overexpression of SPL9 (rSPL9) promoted the expression of C-REPEAT BINDING FACTOR 2 (CBF2) and hereafter enhanced the freezing tolerance. Genetic analysis indicated that the effect of rSPL9 on freezing tolerance is partially restored by cbf2 mutant. Further analysis confirmed that SPL9 directly binds to the promoter of CBF2 to activate the expression of CBF2, and thereafter increased the freezing tolerance. Conclusions Therefore, our study uncovers a new role of SPL9 in fine-tuning CBF2 expression and thus mediating freezing tolerance in plants, and implies a role of miR156-SPL pathway in balancing the vegetative development and freezing response in Arabidopsis.

Mutations in Rht-B1 Locus May Negatively Affect Frost Tolerance in Bread Wheat

“…For example, a recent study indicated that low temperature also induced the SQUAMOSA PROMOTER BINDING PROTEIN-LIKE 9 (SPL9) gene in Arabidopsis plants. SPL9 may directly bind to the promoter of one of the CBF genes, leading to increased freezing tolerance [ 39 ]. Results in Betula luminifera indicated that certain SPLs may also interact with DELLA proteins, influencing the processes regulated by GA [ 40 ].…”

Function of Nuclear Pore Complexes in Regulation of Plant Defense Signaling

“…What are the effects of the particular spatial location of chromatin to the NPC on gene transcription and epigenetic regulation under harsh conditions? (3) Plant ontogenetic defense against abiotic and biotic stresses has been extensively studied [ 119 , 120 , 121 ]. Studies have indicated that NPCs functions in plant developmental transitions.…”

The miR159‐MYB33‐ABI5 module regulates seed germination in Arabidopsis

“…Except for ABA signaling, microRNAs (miRNAs) have been considered one of the most important signaling molecules in response to various stresses and in the regulation of developmental processes in plants (Singh et al, 2021; Wu et al, 2009; Zhao et al, 2022). Of them, miR156 and miR159 interact with each other to regulate plant development (Guo et al, 2017); and they are both altered by abiotic stresses and mediate the stress pathways via independent ways (Cui et al, 2015; Ge et al, 2018; Reyes & Chua, 2007; Singh et al, 2021; Zhao et al, 2022). miR156 targets SQUAMOSA PROMOTER BINDING PROTEIN‐LIKE (SPL) genes to regulate developmental transitions and abiotic stresses, including drought, salt and cold (Arshad et al, 2017; Cui et al, 2015; Gou et al, 2011; Zhao et al, 2022).…”

“…Of them, miR156 and miR159 interact with each other to regulate plant development (Guo et al, 2017); and they are both altered by abiotic stresses and mediate the stress pathways via independent ways (Cui et al, 2015; Ge et al, 2018; Reyes & Chua, 2007; Singh et al, 2021; Zhao et al, 2022). miR156 targets SQUAMOSA PROMOTER BINDING PROTEIN‐LIKE (SPL) genes to regulate developmental transitions and abiotic stresses, including drought, salt and cold (Arshad et al, 2017; Cui et al, 2015; Gou et al, 2011; Zhao et al, 2022). ABA induces miR159 in an ABI3‐dependent manner, it renders plants hyposensitive to ABA by suppressing the expression of its targets, MYB33 and MYB101 (Reyes & Chua, 2007).…”