Cold stress tolerance in pepper: role of transcription factors in molecular signaling and adaptive responses

Functional Divergence of DREB Transcription Factors in Crop Abiotic Stress Tolerance: A Mini-Review

Jasmonate ZIM-domain protein 2 orchestrates ABA/JA signaling and flavonoid biosynthesis to suppress cold tolerance in grapevine.

Low temperature is a significant abiotic stressor that severely constrains grape cultivation and productivity. Jasmonate ZIM-domain (JAZ) proteins, which function as critical transcriptional repressors in the jasmonic acid signaling pathway, play essential roles in plant stress adaptation. Nevertheless, their specific functions and regulatory mechanisms in grape cold tolerance remain unclear. This work investigated the role and regulatory network of a cold-inducible VvJAZ2 gene by integrating physiological, molecular, and transcriptomic approaches. Functional analyses revealed that overexpression of VvJAZ2 compromised cold tolerance in Arabidopsis and grape calli, manifested as aggravated oxidative damage and compromised antioxidant capacity. Furthermore, transgenic materials exhibited decreased endogenous ABA and JA levels, reduced flavonoid accumulation, and downregulation of the ICE-CBF-COR regulatory module. Consistently, transcriptomic profiling further indicated that VvJAZ2 functions as a negative regulator by coordinating the suppression of ABA/JA signaling cascades, MAPK pathway activity, and flavonoid biosynthetic processes. Mechanistically, the transcription factor VvMSA (Abscisic acid-stress-ripening protein) was identified as an upstream activator that directly binds to the VvJAZ2 promoter and induces its expression under normal conditions; however, this activation is markedly attenuated during cold stress. Moreover, VvJAZ2 physically interacts with VvUGT74F5 (UDP-glycosyltransferase 74F5) implicated in flavonoid modification. Collectively, these findings suggest that VvJAZ2 may function as a potential regulatory node, and support a working model of a dynamic "transcription-protein interaction" module to coordinate hormone signaling and metabolic reprogramming under cold stress. This study provides novel insights into the molecular basis of cold adaptation in grapevine and identifies potential genetic targets for improving cold resilience in viticulture.

β-cyclocitral as an apocarotenoid stress signal: biosynthesis, hormonal crosstalk, and emerging omics perspectives in plant abiotic stress tolerance

Abiotic stress, including drought, salinity, heavy metals, and extreme temperatures, severely limits plant growth, productivity, and survival. These stresses frequently occur simultaneously and disrupt cellular homeostasis, photosynthesis, and metabolic processes. To cope with such adverse conditions, plants activate complex physiological, biochemical, and molecular defense mechanisms. Among the emerging stress-related signaling compounds, β-cyclocitral, a β-carotene-derived apocarotenoid, has gained significant attention due to its crucial role in plant stress adaptation. β-Cyclocitral enhances photoprotection by scavenging free radicals and reducing singlet oxygen-mediated damage to photosynthetic machinery. It also modulates reactive oxygen species (ROS) homeostasis through the activation of antioxidant defense systems, thereby minimizing oxidative stress. In parallel, key phytohormones such as abscisic acid (ABA), jasmonic acid (JA), and salicylic acid (SA) regulate diverse stress-responsive pathways that improve plant tolerance and defense. Increasing evidence suggests that β-cyclocitral interacts closely with these hormonal signaling networks to coordinate stress responses and metabolic adjustments. This review highlights recent advances in the biosynthesis, physiological functions, and signaling roles of β-cyclocitral, with particular emphasis on its mechanistic crosstalk with ABA, JA, and SA pathways in enhancing abiotic stress tolerance in plants.

DROUGHT STRESS IN Brassica napus: PHYSIOLOGICAL RESPONSES, MOLECULAR MECHANISMS, AND INTEGRATED MANAGEMENT STRATEGIES

This review synthesizes existing knowledge on the morpho-physiological, biochemical, and molecular response of B. napus to drought stress and emphasizes the importance of phytohormone signaling, osmotic adjustment, and stress response gene and transcription factors in enhancing plant adaptation to drought conditions.

Molecular Mechanisms in Responses to Combined Stresses in Strawberry

Strawberry is a globally important yet stress-sensitive crop, increasingly threatened by combined abiotic and biotic stresses. Unlike single stresses, combined stresses elicit unique, non-additive responses through complex signaling and gene regulatory networks. This review synthesizes current knowledge on the molecular mechanisms underlying strawberry responses to combined stresses, focusing on signal perception and transduction as well as gene regulation. We examine how combined stresses are perceived by membrane-localized sensors and calcium channels, and how these signals are transduced through MAPK (mitogen-activated protein kinase) cascades, CDPKs (calcium-dependent protein kinases), and hormonal crosstalk involving ABA (abscisic acid), JA (jasmonic acid), and ethylene. At the gene regulation level, we discuss the roles of key transcription factors (WRKY, NAC (NAM, ATAF1, ATAF2 and CUC2), GRAS (GAI-RGA-and-SCR), DREB (Dehydration-Responsive Element-Binding protein), bZIP (basic leucine zipper transcription factor), CAMTA (calmodulin-binding transcription activator), ARF (auxin response factor), and LAV (Leafy Cotyledon2–Abscisic Acid Insensitive3–Val)), transcriptional cascades, epigenetic regulation via DNA methylation, and post-transcriptional (miRNAs such as Fan-miR73) and post-translational (ubiquitination and phosphorylation) control mechanisms. The review also evaluates emerging mitigation strategies informed by these molecular insights, including genomic selection, and explores future directions such as CRISPR (clustered regularly interspaced short palindromic repeats)-based genome editing and multi-omics integration. We conclude that understanding the integrated signaling and gene regulatory networks is essential for developing climate-resilient strawberry cultivars capable of withstanding increasingly complex stress combinations.

Overexpression of PlPAT1, a GRAS transcription factor from Paeonia lactiflora, enhances salt stress tolerance in transgenic tobacco

It is demonstrated that PlPAT1 functions as a positive regulator of salt stress tolerance, likely through modulating osmotic balance and enhancing reactive oxygen species scavenging capacity.