The WRKY transcription factor (TF) family is one the largest plant-specific transcription factor families. It has been proven to play significant roles in multiple plant biological processes, especially stress response. Although many WRKY TFs have been identified in various plant species, WRKYs in white birch (Betula platyphylla Suk.) remain to be studied. Here, we identified a total of 68 BpWRKYs, which could be classified into four main groups. The basic physiochemical properties of these TFs were analyzed using bioinformatics tools, including molecular weight, isoelectric point, chromosome location, and predicted subcellular localization. Most BpWRKYs were predicted to be located in the nucleus. Synteny analysis found 17 syntenic gene pairs among BpWRKYs and 52 syntenic gene pairs between BpWRKYs and AtWRKYs. The cis-acting elements in the promoters of BpWRKYs could be enriched in multiple plant biological processes, including stress response, hormone response, growth and development, and binding sites. Tissue-specific expression analysis using qRT-PCR showed that most BpWRKYs exhibited highest expression levels in the root. After ABA, salt (NaCl), or cold treatment, different BpWRKYs showed different expression patterns at different treatment times. Furthermore, the results of the Y2H assay proved the interaction between BpWRKY17 and a cold-responsive TF, BpCBF7. By transient expression assay, BpWRKY17 and BpWRKY67 were localized in the nucleus, consistent with the previous prediction. Our study hopes to shed light for research on WRKY TFs and plant stress response.
CBF (C-repeat binding factor) transcription factor subfamily belongs to AP2/ERF (Apetala 2/ethylene-responsive factor) transcription factor family, known for playing a vital role in plant abiotic stress response. Although some CBF transcription factors have been identified in several species, such as Arabidopsis, tobacco, tomato and poplar, research of CBF focus mainly on model plant Arabidopsis and have not been reported in Betula platyphylla yet. In this study, a total of 20 BpCBF subfamily members were identified. The conserved domains, physicochemical properties, exon-intron gene structure and the structure of conserved protein motifs of BpCBFs were analyzed via bioinformatic tools. The collinearity analysis of CBF genes was performed between Betula platyphylla and Arabidopsis thaliana, Betula platyphylla, and Populus trichocarpa. The cis-acting elements in the promoter region of BpCBFs were identified, which were mainly environmental stress-related and hormone-related element components. In this case, the expression patterns of the 20 BpCBFs upon ABA or salt treatment were investigated. Most of these transcription factors were responsive to ABA or salt stress in different plant tissues. The up-regulation trend upon cold treatment of the six cold-responsive genes validated by qRT-PCR was consistent with the result of RNA-seq. BpCBF7 showed transcription activating activity. This study sheds light on the responses of BpCBFs to abiotic stress and provides a reference for further study of CBF transcription factors in woody plants.
As a globally popular crop, strawberry is highly susceptible to cold stress, which significantly limits its cultivation and yield. This review synthesizes current knowledge on the morphological, physiological, and molecular responses of strawberry plants to cold stress. Morphologically, cold stress induces chlorosis, necrosis, and growth retardation, while physiologically, it impairs photosynthesis and membrane integrity and triggers oxidative stress. At the molecular level, the cold acclimation process in plants is orchestrated by a sophisticated regulatory network centered on the ICE-CBF/DREB signaling pathway and incorporating transcription factors, epigenetic modifications, and non-coding RNAs. The accumulation of protective compounds like proline, anthocyanins, and antioxidants is a key metabolic adaptation. Finally, we discuss integrative management practices and future breeding strategies, including genetic engineering, marker-assisted selection, and the use of plant growth-promoting rhizobacteria to enhance cold tolerance. This comprehensive overview provides valuable insights for developing resilient strawberry varieties in the face of unpredictable climate events.
Nuclear Factor Y A (NF-YA) transcription factors are widely involved in multiple plant biological processes, such as embryogenesis, abscisic acid signaling, and abiotic stress response. This study presents a comprehensive genome-wide identification and expression profiling of NF-YA transcription factors in blueberry (Vaccinium corymbosum), an important economic crop with good adaptability, under abiotic stress conditions. Given the economic significance and health benefits of blueberries, understanding their responses to environmental stresses, such as salt, drought, and temperature extremes, is crucial. A total of 24 NF-YA transcription factors were identified through bioinformatics analyses, including sequence alignment, phylogenetic tree construction, and conserved motif analysis. The expression patterns of these NF-YA genes were evaluated in various tissues (roots, stems, and leaves) and under different stress treatments (abscisic acid, salt, and cold) using quantitative real-time PCR (qRT-PCR). The results indicated that most VcNF-YA genes exhibited higher expression levels in stems and leaves compared to roots. Most VcNF-YAs were responsive to the stress treatment. Furthermore, cis-acting element analysis revealed that the promoters of VcNF-YAs were enriched with elements responsive to abiotic stress, suggesting their pivotal role in stress adaptation. This research unveils the expressional responses of NF-YA transcription factors in blueberry upon abiotic stresses and lays the groundwork for future studies on improving crop adaptation.
In this study, the poplar doubled haploid (DH) plants were used as the experimental material to explore the huge phenotypic differences between homozygous DH plants and the paternal plants, and the molecular regulation mechanism of the differential phenotypes. In this experiment, through morphological and histological observation and statistics, we found that the double haploid plants had significantly reduced plant height and ground diameter, increased leaf aspect ratio, premature senescence phenotype of top bud, and significant changes in the shape and cell area of the shoot apical meristem. Significantly differentially expressed genes were obtained using RNA-seq transcriptome sequencing. They were subjected to GO enrichment and KEGG analysis. Transcription factors with key functions were screened out for qRT-PCR to verify gene expression changes to predict gene function. The results showed that after the IAA and ABA treatment, the expression levels of some hormone-responsive genes in wild type plants were significantly changed with different treatment time. In the dihaploid plants, the corresponding genes also changed to different degrees, which reflected the changes in the response of the dihaploid plants to hormones. Compared to in WT, the differential expressed genes in the double haploids were involved in multiple physiological process such as response to oxidative stress, response to salicylic acid, plant pathogen interaction, and plant hormone signal transduction. A TF–centered gene regulatory network for phytohormone synthesis and plant senescence was constructed with the expression patterns of differentially expressed transcription factors (TFs). This study increases researchers’ understanding of the regulation of poplar growth and development and provides new research ideas for the creation of new species of poplar.
Nuclear Factor Y (NF-Y) transcription factor family plays essential roles in plant growth, development, and abiotic stress responses. However, the NF-YA subfamily in cultivated strawberry (Fragaria × ananassa) has not been systematically characterized from a genome-wide range. In this study, 27 FaNF-YA genes were identified from the octoploid strawberry genome and classified into four phylogenetic groups. With bioinformatic methods, it was found that all FaNF-YA proteins contain a highly conserved CCAAT-binding domain, while their exon–intron structures and motif compositions vary among groups. Promoter cis-acting element analysis revealed various stress- and hormone-responsive motifs, including ABRE, MYB, MYC, and MeJA-responsive elements. With molecular biology methods, organ-specific expression profiling was generated and showed that FaNF-YA genes exhibit distinct spatial expression patterns, with extremely low transcript abundance in fruit. Under salt stress, several FaNF-YA groups (e.g., FaNF-YA14/16/18/22) were dramatically induced, which indicated their potential involvement in salt tolerance. Heterologous expression of FaNF-YA7 and FaNF-YA9 in yeast enhanced salt tolerance, and these two proteins did not exhibit transcription-activating activity in the yeast GAL4 system. This study provides a reference for understanding the roles of NF-YA genes in responses to abiotic stresses and potential targets for molecular breeding of stress-tolerant strawberry cultivars.