Journal of Integrative Plant Biology最新文献

Nicotiana benthamiana requires the coiled-coil nucleotide-binding leucine-rich repeat receptor protein NbZAR1 to recognize the type III effector RipP1 from Ralstonia solanacearum. Moreover, RipP1-induced cell death and immunity relies on EDS1 and NRG1, two core components of the Toll-interleukin 1-like receptor nucleotide-binding leucine-rich repeat receptor signaling pathway.

Incorporating genotype-by-environment (GE) interaction effects into genomic prediction (GP) models with multi-environment climate data can improve selection accuracy to accelerate crop breeding but has received little research attention. Here, we conducted a cross-region GP study of grain moisture content (GMC) and grain yield (GY) in maize hybrids in two major Chinese growing regions using data for 19 climatic factors across 34 environments in 2020 and 2021. Predictions were conducted in 2,126 hybrids generated from 475 maize inbred lines, using 9,355 single nucleotide polymorphism markers for genotyping. Models based on genomic best linear unbiased prediction (GBLUP) incorporating GE interaction effects of 19 climatic factors associated with day length, transpiration, temperature, and radiation (GBLUP-GE_19CF) trained on whole data set outperformed the traditional GBLUP or BayesB models in predicting GMC or GY by 10-fold cross-validation, achieving prediction accuracies of 0.731 and 0.331, respectively. To refine the climate data, we examined 84 statistical features associated with these climatic factors and identified nine factors most correlated with GMC or GY. Principal component analysis of climate data yielded nine principal components responsible for 97% of the variability in the data. Incorporating these nine factors or principal components into the GBLUP-GE framework with a similarity matrix of environments (GBLUP-GE_9CF and GBLUP-GE_PCA) provided similar prediction accuracies but could reduce the computational burden. In addition, increasing the number of test set environments in the training set from 8 to 14 increased the prediction accuracy of GBLUP-GE_19CF trained with monthly average climate data for 2020-2021. Examining prediction accuracy based on concordance, the proportion of overlapping hybrids between the top 50% of predicted and observed values for GMC and GY, indicated that concordance exceeded 50% for the GBLUP-GE_19CF model, confirming the reliability of our predictions. This study can provide practical guidance for optimizing GPs for maize breeding programs in multi-environment selection.

Flowering time is a critical agronomic trait in rice, directly influencing grain yield and adaptability to specific planting regions and seasons. Florigens, including FLOWERING LOCUS T (FT) proteins Hd3a (OsFTL2) and RFT1 (OsFTL3), play central roles in transmitting flowering signals through rice's photoperiod regulatory network. While Hd3a and RFT1 have been extensively studied, the functions and interactions of other FT-like proteins remain unclear, limiting advancements in breeding strategies for early-maturing rice varieties. Here, we demonstrate that the florigen-like protein OsFTL1 forms a florigen activation complex (FAC) and promotes flowering under both short-day and long-day conditions. OsFTL1 localizes to the nucleus and cytoplasm, with predominant expression in the shoot base, facilitating its mobilization to the shoot apical meristem (SAM) to initiate flowering. Overexpression of OsFTL1 (OsFTL1-OE) in leaves or shoot bases significantly accelerates flowering and alters plant architecture. In the nucleus, OsFTL1 interacts with GF14c and OsFD1 to form an FAC, activating OsMADS14 and OsMADS15 expression to drive flowering. Markedly, OsFTL1-OE plants deficient in Hd3a and RFT1 exhibited earlier flowering compared with wild-type plants, indicating that OsFTL1 can independently promote flowering. Furthermore, haplotype analysis identified OsFTL1-Hap3, a beneficial variant associated with early flowering and comparable grain yields. These findings revealed that OsFTL1 can substitute for Hd3a and RFT1 in FAC formation, promoting flowering across photoperiods, and highlighting its potential application in breeding early-maturing, high-yield rice varieties suitable for diverse environments.

NAC (NAM, ATAF1/2, and CUC2) transcription factors (TFs) are a family of plant-specific TFs that play crucial roles in various aspects of plant development and stress responses. Here, we provide an in-depth review of the structural characteristics, regulatory mechanisms, and functional roles of NACs in different plant species. One of the key features of NACs is their ability to regulate gene expression through a variety of mechanisms, including binding to DNA sequences in the promoter regions of target genes, interacting with other TFs, and modulating chromatin structure. We discuss these mechanisms in detail, providing insights into the complex regulatory networks that govern the activity of NACs. We explore the diverse functions of these TFs in plant growth and development processes, including embryogenesis, seed development, root and shoot development, floral development and fruit ripening, secondary cell wall formation, and senescence. We also discuss the diverse regulatory roles of NACs in response to various stresses, including drought, flooding, heat, cold, salinity, nutrient deficit, and diseases. Lastly, we emphasize the crosstalk role of NACs between developmental processes and stress responses. This integrated perspective highlights how NACs orchestrate plant growth and resilience. Overall, this review provides a comprehensive overview of the pivotal roles of NACs in plant development and stress responses, emphasizing their potential for engineering stress-resistant crops and enhancing agricultural productivity.

Targeted knockout of the betaine aldehyde dehydrogenase genes AhBADH1 and AhBADH2 using CRISPR/Cas9 produced peanut mutant lines with significantly elevated 2-acetyl-1-pyrroline levels and a strong aroma, marking the first creation of fragrant peanut lines.

Increasing plant density has been recognized as an effective strategy for boosting maize yields over the past few decades. However, dense planting significantly reduces the internal light intensity and the red to far-red (R:FR) light ratio in the canopy, which subsequently triggers shade avoidance responses (SAR) that limit further yield enhancements, particularly under high-density conditions. In this study, we identified double B-box containing protein DBB2, a member of the ZmBBX family that is rapidly induced by shade, as a crucial regulator of plant height and SAR. Disruption of DBB2 resulted in shorter internodes, reduced plant height, decreased cell elongation, and diminished sensitivity to shade in maize, effects that can be largely alleviated by external treatment with gibberellins (GA). Furthermore, we discovered that DBB2 physically interacted with the transcription factor HY5, inhibiting its transcriptional activation of ZmGA2ox4, a gene encoding a GA2 oxidase that can deactivate GA. This interaction positively influences maize plant height through the GA pathway. Additionally, we found that the induction of ZmDBB2 by shade is mediated by the transcription factor PIF4. Interestingly, DBB2 then interacted with PIF4 to enhance the transcriptional activation of cell elongation-related genes, such as ZmEXPA1, thereby establishing a positive feedback loop promoting cell elongation under canopy shade conditions. Our findings highlight the critical role of BBX proteins in modulating plant height and SAR, presenting them as key genetic targets for developing maize varieties suited to high-density planting conditions. This study also provides new insights into the molecular mechanisms underlying SAR and offers potential strategies for the genetic improvement of maize plant architecture and grain yield.

Grain size is a key determinant of 1,000-grain weight, one of three factors determining grain yield. However, the complete regulatory network controlling grain size has not been fully clarified. Here, we identified a rice mutant, named small and round grain (srg) that exhibits semi-dwarf stature and small grain size. Cytological analysis showed that cell length and number of spikelet epidermal cells of the srg mutant are reduced, indicating that SRG controls grain size by promoting cell elongation and increasing cell number. SRG encodes a kinesin belonging to the kinesin-1 subfamily and is extensively expressed in different plant tissues with relatively high expression in young panicles. SRG protein is mainly located in the nucleus and cell membrane. Expression of the SRG gene was induced by brassinolide through the brassinosteroid (BR) responsive factor OsWRKY53 and SRG protein was phosphorylated by BR-activated kinase OsBSK3 to prevent its degradation. In addition, microtubule (MT) morphology was abnormal and disordered in the srg and cr-1 mutants. These findings suggest that BR likely stabilizes orderly assembly and arrangement of MTs by stabilizing SRG proteins, thus promoting grain size. SRG overexpression lines produced more tillers and significantly larger and heavier grains to increase 1,000-grain weight, suggesting that SRG has potential to increase grain yield. Our study indicated that SRG is a new BR responsive factor and BR might regulate grain size by influencing the expression of SRG.

Jasmonic acid (JA) and gibberellin (GA) coordinate many aspects of plant growth and development, including anthocyanin biosynthesis. However, the crossover points of JA and GA signals and the pathways through which they interact to regulate anthocyanin biosynthesis are poorly understood. Here, we investigated the molecular mechanism by which the zinc finger protein (ZFP) transcription factor Malus domestica ZFP7 (MdZFP7) regulates anthocyanin biosynthesis by integrating JA and GA signals at the transcriptional and post-translational levels. MdZFP7 is a positive regulator of anthocyanin biosynthesis, which fulfills its role by directly activating the expression of MdMYB1 and enhancing the transcriptional activation of MdWRKY6 on the target genes MdDFR and MdUF3GT. MdZFP7 integrates JA and GA signals by interacting with the JA repressor apple JASMONATE ZIM-DOMAIN2 (MdJAZ2) and the GA repressor apple REPRESSOR-of-ga1-3-like 3a (MdRGL3a). MdJAZ2 weakens the transcriptional activation of MdMYB1 by MdZFP7 and disrupts the MdZFP7-MdWRKY6 interaction, thereby reducing the anthocyanin biosynthesis promoted by MdZFP7. MdRGL3a contributes to the stimulation of anthocyanin biosynthesis by MdZFP7 by sequestering MdJAZ2 from the MdJAZ2-MdZFP7 complex. The E3 ubiquitin ligase apple BOI-related E3 ubiquitin-protein ligase 3 (MdBRG3), which is antagonistically regulated by JA and GA, targets the ubiquitination degradation of MdZFP7. The MdBRG3-MdZFP7 module moves the crosstalk of JA and GA signals from the realm of transcriptional regulation and into the protein post-translational modification. In conclusion, this study not only elucidates the node-role of MdZFP7 in the integration of JA and GA signals, but also describes the transcriptional and post-translational regulatory network of anthocyanin biosynthesis with MdZFP7 as the hub.

This commentary on Zeng et al. (2025, Cell) discusses the role of COOL1 in maize cold adaptation, highlighting its significance for high-latitude adaptation and the potential for molecular design breeding to enhance cold tolerance in maize.

Citrus have been cultivated more than 4,000 years and have become globally valued as fresh fruit and for making juice. Citrus fruits contain many types of antioxidants, including a diverse array of carotenoids, which contribute to their colors. The cover shows cross-sections of citrus fruits arranged in a spiral pattern and displaying a stunning array of colors, from white and pale yellow to grapefruit pink, blood red, golden yellow, and vibrant orange. These slices, varying in size and hue highlight the richness and diversity of citrus fruits and emphasizing the vibrant palette of citrus carotenoids. Sun et al. (pages 294-310) identified CitZAT4 as a key regulator of carotenoid accumulation, providing valuable strategies for breeding citrus varieties with enhanced quality and nutritional value, thereby boosting the economic benefits of the citrus industry.