Improved abiotic stress tolerance in Arabidopsis by constitutive active form of a banana DREB2 type transcription factor, MaDREB20.CA, than its native form, MaDREB20

Shaping the future of bananas: advancing genetic trait regulation and breeding in the postgenomics era

Bananas (Musa spp.) are among the top-produced food crops, serving as a primary source of food for millions of people. Cultivated bananas originated primarily from the wild diploid species Musa acuminata (A genome) and Musa balbisiana (B genome) through intra- and interspecific hybridization and selections via somatic variation. Following the publication of complete A- and B-genome sequences, prospects for complementary studies on S- and T-genome traits, key gene identification for yield, ripening, quality, and stress resistance, and advances in molecular breeding have significantly expanded. In this review, latest research progress on banana A, B, S, and T genomes is briefly summarized, highlighting key advances in banana cytoplasmic inheritance, flower and fruit development, sterility, and parthenocarpy, postharvest ripening and quality regulation, and biotic and abiotic stress resistance associated with desirable economic traits. We provide updates on transgenic, gene editing, and molecular breeding. We also explore future directions for banana breeding and genetic improvement.

Exploring lipid signaling in plant physiology: From cellular membranes to environmental adaptation

Lipids have evolved as versatile signaling molecules that regulate a variety of physiological processes in plants. Convincing evidence highlights their critical role as mediators in a wide range of plant processes required for survival, growth, development, and responses to environmental conditions such as water availability, temperature changes, salt, pests, and diseases. Understanding lipid signaling as a critical process has helped us expand our understanding of plant biology by explaining how plants sense and respond to environmental cues. Lipid signaling pathways constitute a complex network of lipids, enzymes, and receptors that coordinate important cellular responses and stressing plant biology's changing and adaptable traits. Plant lipid signaling involves a wide range of lipid classes, including phospholipids, sphingolipids, oxylipins, and sterols, each of which contributes differently to cellular communication and control. These lipids function not only as structural components, but also as bioactive molecules that transfer signals. The mechanisms entail the production of lipid mediators and their detection by particular receptors, which frequently trigger downstream cascades that affect gene expression, cellular functions, and overall plant growth. This review looks into lipid signaling in plant physiology, giving an in-depth look and emphasizing its critical function as a master regulator of vital activities.

Oil Palm AP2 Subfamily Gene EgAP2.25 Improves Salt Stress Tolerance in Transgenic Tobacco Plants

AP2/ERF transcription factor genes play an important role in regulating the responses of plants to various abiotic stresses, such as cold, drought, high salinity, and high temperature. However, less is known about the function of oil palm AP2/ERF genes. We previously obtained 172 AP2/ERF genes of oil palm and found that the expression of EgAP2.25 was significantly up-regulated under salinity, cold, or drought stress conditions. In the present study, the sequence characterization and expression analysis for EgAP2.25 were conducted, showing that it was transiently over-expressed in Nicotiana tabacum L. The results indicated that transgenic tobacco plants over-expressing EgAP2.25 could have a stronger tolerance to salinity stress than wild-type tobacco plants. Compared with wild-type plants, the over-expression lines showed a significantly higher germination rate, better plant growth, and less chlorophyll damage. In addition, the improved salinity tolerance of EgAP2.25 transgenic plants was mainly attributed to higher antioxidant enzyme activities, increased proline and soluble sugar content, reduced H2O2 production, and lower MDA accumulation. Furthermore, several stress-related marker genes, including NtSOD, NtPOD, NtCAT, NtERD10B, NtDREB2B, NtERD10C, and NtP5CS, were significantly up-regulated in EgAP2.25 transgenic tobacco plants subjected to salinity stress. Overall, over-expression of the EgAP2.25 gene significantly enhanced salinity stress tolerance in transgenic tobacco plants. This study lays a foundation for further exploration of the regulatory mechanism of the EgAP2.25 gene in conferring salinity tolerance in oil palm.

Phytosulfokine promotes fruit ripening and quality via phosphorylation of transcription factor DREB2F in tomato

Phytosulfokine (PSK), a plant peptide hormone with a wide range of biological functions, is recognized by its receptor PHYTOSULFOKINE RECEPTOR 1 (PSKR1). Previous studies have reported that PSK plays important roles in plant growth, development, and stress responses. However, the involvement of PSK in fruit development and quality formation remains largely unknown. Here, using tomato (Solanum lycopersicum) as a research model, we show that exogenous application of PSK promotes the initiation of fruit ripening and quality formation, while these processes are delayed in pskr1 mutant fruits. Transcriptomic profiling revealed that molecular events and metabolic pathways associated with fruit ripening and quality formation are affected in pskr1 mutant lines and transcription factors are involved in PSKR1-mediated ripening. Yeast screening further identified that DEHYDRATION-RESPONSIVE ELEMENT BINDING PROTEIN 2F (DREB2F) interacts with PSKR1. Silencing of DREB2F delayed the initiation of fruit ripening and inhibited the promoting effect of PSK on fruit ripening. Moreover, the interaction between PSKR1 and DREB2F led to phosphorylation of DREB2F. PSK improved the efficiency of DREB2F phosphorylation by PSKR1 at the tyrosine-30 site, and the phosphorylation of this site increased the transcription level of potential target genes related to the ripening process and functioned in promoting fruit ripening and quality formation. These findings shed light on the involvement of PSK and its downstream signaling molecule DREB2F in controlling climacteric fruit ripening, offering insights into the regulatory mechanisms governing ripening processes in fleshy fruits.

The DREB transcription factor, a biomacromolecule, responds to abiotic stress by regulating the expression of stress-related genes

Abiotic stress is a crucial factor that affects plant survival and growth and even leads to plant death in severe cases. Transcription factors can enhance the ability of plants to fight against various stresses by controlling the expression of downstream genes. The dehydration response element binding protein (DREB) is the most extensive subfamily of AP2/ERF transcription factors involved in abiotic stress. However, insufficient research on the signal network of DREB transcription factors has limited plant growth and reproduction. Furthermore, field planting of DREB transcription factors and their roles under multiple stress also require extensive research. Previous reports on DREB transcription factors have focused on the regulation of DREB expression and its roles in plant abiotic stress. In recent years, there has been new progress in DREB transcription factors. Here, the structure and classification, evolution and regulation, role in abiotic stress, and application in crops of DREB transcription factors were reviewed. And this paper highlighted the evolution of DREB1/CBF, as well as the regulation of DREB transcription factors under the participation of plant hormone signals and the roles of subgroups in abiotic stress. In the future, it will lay a solid foundation for further study of DREB transcription factors and pave the way for the cultivation of resistant plants.