OsNF-YA3 regulates plant growth and osmotic stress tolerance by interacting with SLR1 and SAPK9 in rice

ZmNF-YB10, a maize NF-Y transcription factor, positively regulates drought and salt stress response in Arabidopsis thaliana

Maize (Zea mays L.) is a major food and feed crop and an important raw material for energy, chemicals, and livestock. The NF-Y family of transcription factors in maize plays a crucial role in the regulation of plant development and response to environmental stress. In this study, we successfully cloned and characterized the maize NF-Y transcription factor gene ZmNF-YB10. We used bioinformatics, quantitative fluorescence PCR, and other techniques to analyze the basic properties of the gene, its tissue expression specificity, and its role in response to drought, salt, and other stresses. The results indicated that the gene was 1209 base pairs (bp) in length, with a coding sequence (CDS) region of 618 bp, encoding a polypeptide composed of 205 amino acid residues. This polypeptide has a theoretical isoelectric point of 5.85 and features a conserved structural domain unique to the NF-Y family. Quantitative fluorescence PCR results demonstrated that the ZmNF-YB10 gene was differentially upregulated under drought and salt stress treatments but exhibited a negatively regulated expression pattern under alkali and cold stress treatments. Transgenic Arabidopsis thaliana subjected to drought and salt stress in soil showed greener leaves than wild-type A. thaliana. In addition, the overexpression lines showed reduced levels of hydrogen peroxide (H2O2), superoxide (O2-), and malondialdehyde (MDA) and increased activities of peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD). Western blot analysis revealed a distinct band at 21.8 kDa. Salt and drought tolerance analyses conducted in E. coli BL21 indicated a positive regulation. In yeast cells, ZmNF-YB10 exhibited a biological function that enhances salt and drought tolerance. Protein interactions were observed among the ZmNF-YB10, ZmNF-YC2, and ZmNF-YC4 genes. It is hypothesized that the ZmNF-YB10, ZmNF-YC2, and ZmNF-YC4 genes may play a role in the response to abiotic stresses, such as drought and salt tolerance, in maize.

Soybean transcription factor GmNF-YB20 confers resistance to stripe rust in transgenic wheat by regulating nonspecific lipid transfer protein genes

Worldwide food security is severely threatened by the devastating wheat stripe rust disease. The utilization of resistant wheat cultivars represents the most cost-effective and efficient strategy for combating this disease. However, the lack of resistant resources has been a major bottleneck in breeding for wheat disease resistance. Therefore, revealing novel gene resources for combating stripe rust and elucidating the underlying resistance mechanism is of utmost urgency. In this study, we identified that the soybean NF-YB transcription factor GmNF-YB20 in wheat provides resistance to the stripe rust fungus (Puccinia striiformis f. sp. tritici, Pst). Wheat lines with stable overexpression of the GmNF-YB20 enhanced resistance against multiple Pst races. Transcriptome profiling of GmNF-YB20 transgenic wheat under Pst infection unveiled its involvement in the lipid signaling pathway. RT-qPCR assays suggested that GmNF-YB20 increased transcript levels of multiple nonspecific lipid transfer protein (LTP) genes during wheat-Pst interaction, luciferase reporter analysis illustrates that it activates the transcription of TaLTP1.50 in wheat protoplast, and GmNF-YB20 overexpressed wheat plants had higher total LTP content in vivo during Pst infection. Overexpression of TaLTP1.50 in wheat significantly increased resistance to Pst, whereas knockdown of TaLTP1.50 exhibited the opposite trends, indicating that TaLTP1.50 plays a positive role in wheat resistance. Taken together, our findings provide perspective regarding the molecular mechanism of GmNF-YB20 in wheat and highlight the potential use for wheat breeding.

MaMPK19, a key gene enhancing cold resistance by activating the CBF pathway in banana

MPKs play an essential part role in the process of plant low temperature stress. In this study, the specific inhibitor SB203580 of MPK was used to spray banana leaves and MaMPK19 was overexpressed in N.benthamiana and banana to explore the effect of MaMPK19 on cold resistance and the regulation mode of downstream genes. Additionally, we optimized the method of genetic transformation of banana laying the foundation for the establishment of an efficient genetic transformation system. The results showed that 40 μmol L-1 SB203580 could significantly reduce the expression of MaMPK19 and MaCBFs, as well as weaken the cold resistance of banana at 4 °C. After agrobacterium tumefaciens infection, the regeneration rates of adventitious buds in 'Tianbao', 'Brazilian' and'Indonesia' (Musa spp. AAA Group, Cavendish) reached 10.43%, 15.81% and 14.23%, respectively. And the positive rates reached 10.71%, 2.25% and 6.94%, respectively. Overexpression of MaMPK19 enhanced the cold resistance of N.benthamiana and bananas. MaMPK19 promoted the expression of MaICE1, MaDREB1D and MaCOR413. Furthermore, MaMPK19 increased POD activity and the content of ABA and JA. Our study highlights the importance of MaMPK19 in improving the cold resistance of bananas and provides a reference for biological breeding.

Knockdown of SlYTHDF2 Accelerates Dark-Induced Tomato Leaf Senescence by Affecting the ABA Pathway

N6-methyladenosine (m6A) is a widespread post-transcriptional modification in eukaryotic mRNAs. Proteins with the YTH structural domain act as m6A-binding proteins by recognizing the m6A modification and regulating mRNA through this recognition. In this study, SlYTHDF2, a prototypical m6A -binding protein gene in the YTH family was expressed in various tissues, and subcellular localization analyses indicated that the SlYTHDF2 protein was localized in the nucleus and cytoplasm. SlYTHDF2 knockout lines were obtained using CRISPR/Cas9 technology and showed the senesced leaves prematurely increased endogenous ABA accumulation compared with the wild type. Moreover, we found that dark promoted leaf senescence in SlYTHDF2 knockout lines and exogenous ABA further accelerated leaf senescence under dark conditions. The qRT-PCR analysis revealed significant alterations in the expression of genes associated with the ABA pathway. Relative to the wild type, the CR-slythdf2 plants exhibited reduced levels of photosynthetic pigments, higher accumulation of reactive oxygen species, and increased damage to cell membranes. Additionally, we discovered that SlYTHDF2 interacts with the chloroplast-binding protein SlRBCS3 through yeast two-hybrid and BiFC experiments. Overall, our data suggest the important role of SlYTHDF2 in regulating tomato leaf senescence.

An AP2/ERF transcription factor confers chilling tolerance in rice

Cold stress, a prominent adverse environmental factor, severely hinders rice growth and productivity. Unraveling the complex mechanisms governing chilling tolerance in rice is crucial for molecular breeding of cold-tolerant varieties. Here, we identify an APETALA2/Ethylene Responsive Factor (AP2/ERF) transcription factor, OsERF52, as a positive modulator in response to low temperatures. OsERF52 directly regulates the expression of C-Repeat Binding Factor (CBF) genes in rice. In addition, Osmotic Stress/ABA-Activated Protein Kinase 9-mediated phosphorylation of OsERF52 at S261 enhances its stability and interaction with Ideal Plant Architecture 1 and OsbHLH002/OsICE1. This collaborative activation leads to the expression of OsCBFs, thereby initiating the chilling response in rice. Notably, plants with base-edited OsERF52S261D-3HA exhibit enhanced chilling resistance without yield penalty. Our findings unveil the mechanism orchestrated by a regulatory framework involving a protein kinase and transcription factors from diverse families, offering potential genetic resources for developing chilling-tolerant rice varieties.

Ascorbic acid releases dormancy and promotes germination by an integrated regulation of abscisic acid and gibberellin in Pyrus betulifolia seeds

Seed dormancy is an important life history state in which intact viable seeds delay or prevent germination under suitable conditions. Ascorbic acid (AsA) acts as a small molecule antioxidant, and breaking seed dormancy and promoting subsequent growth are among its numerous functions. In this study, a germination test using Pyrus betulifolia seeds treated with exogenous AsA or AsA synthesis inhibitor lycorine (Lyc) and water absorption was conducted. The results indicated that AsA released dormancy and increased germination and 20 mmol L-1 AsA promoted cell division, whereas Lyc reduced germination. Seed germination showed typical three phases of water absorption; and seeds at five key time points were sampled for transcriptome analysis. It revealed that multiple pathways were involved in breaking dormancy and promoting germination through transcriptome data, and 12 differentially expressed genes (DEGs) related to the metabolism and signal transduction of abscisic acid (ABA) and gibberellins (GA) were verified by subsequent RT-qPCR. For metabolites, exogenous AsA increased endogenous AsA and GA3 but reduced ABA and the ABA/GA3 ratio. In addition, three genes regulating ABA synthesis were downregulated by AsA, while five genes mediating ABA degradation were upregulated. Taken together, AsA regulates the pathways associated with ABA and GA synthesis, catalysis, and signal transduction, with subsequent reduction in ABA and increase in GA and further the balance of ABA/GA, ultimately releasing dormancy and promoting germination.

The cytochrome P450 gene, MdCYP716B1, is involved in regulating plant growth and anthracnose resistance in apple

Apple is one of the main cultivated fruit trees worldwide. Both biotic and abiotic stresses, especially fungal diseases, have serious effects on the growth and fruit quality of apples. Cytochrome P450, the largest protein family in plants, is critical for plant growth and stress responses. However, the function of apple P450 remains poorly understood. In our previous study, 'Hanfu' autotetraploid showed dwarfism and fungal resistance phenotypes compared to 'Hanfu' diploid. Digital gene expression sequencing analysis revealed that the transcript level of MdCYP716B1 was significantly downregulated in the autotetraploid apple cultivar 'Hanfu'. In this study, we identified and cloned the MdCYP716B1 gene from 'Hanfu' apples. The MdCYP716B1 protein fused to a green fluorescent protein was localized in the cytoplasm. We constructed the plant overexpression vector and RNAi vector of MdCYP716B1, and the apple 'GL-3' was transformed by Agrobacterium-mediated transformation to obtain transgenic plants. Overexpressing and RNAi silencing transgenic plants exhibited an increase and decrease in plant height to 'GL-3', respectively. RNAi silencing transgenic plants displayed increased resistance to Colletotrichum gloeosporioides, whereas overexpression transgenic plants were more sensitive to C. gloeosporioides. According to transcriptome analysis, the transcript levels of gibberellin biosynthesis genes were upregulated in MdCYP716B1-overexpression plants. In contrast with 'GL-3', GA3 accumulation was rose in MdCYP716B1-OE lines and impaired in MdCYP716B1-RNAi lines. Collectively, our data indicate that MdCYP716B1 regulates plant growth and resistance to fungal stress.

Recent Molecular Aspects and Integrated Omics Strategies for Understanding the Abiotic Stress Tolerance of Rice

Rice is an important staple food crop for over half of the world's population. However, abiotic stresses seriously threaten rice yield improvement and sustainable production. Breeding and planting rice varieties with high environmental stress tolerance are the most cost-effective, safe, healthy, and environmentally friendly strategies. In-depth research on the molecular mechanism of rice plants in response to different stresses can provide an important theoretical basis for breeding rice varieties with higher stress resistance. This review presents the molecular mechanisms and the effects of various abiotic stresses on rice growth and development and explains the signal perception mode and transduction pathways. Meanwhile, the regulatory mechanisms of critical transcription factors in regulating gene expression and important downstream factors in coordinating stress tolerance are outlined. Finally, the utilization of omics approaches to retrieve hub genes and an outlook on future research are prospected, focusing on the regulatory mechanisms of multi-signaling network modules and sustainable rice production.