Molecular Plant最新文献

Cotton is the world's most important natural fiber crop and serves as an ideal model for studying plant genome evolution, cell differentiation, elongation, and cell wall biosynthesis. The first draft of the cotton genome for Gossypium raimondii, completed in 2012, marked the beginning of global efforts in cotton genomics. Over the past decade, the cotton research community has continued to assemble and refine genomes for both wild and cultivated Gossypium species. With the accumulation of de novo genome assemblies and resequencing data across cotton populations, significant progress has been made in uncovering the genetic basis of key agronomic traits. Achieving the goal of cotton genomics-to-breeding (G2B) will require a deeper understanding of the spatiotemporal regulatory mechanisms involved in genome information storage and expression. We advocate for a cotton ENCODE project to systematically decode the functional elements and regulatory networks within the cotton genome. Technological advances, particularly in single-cell sequencing and high-resolution spatiotemporal omics, will be essential in elucidating these regulatory mechanisms. By integrating multi-omics data, genome editing tools, and artificial intelligence, these efforts will empower the genomics-driven strategies needed for future cotton G2B breeding.

The intricate interplay between cellular circadian rhythms, primarily manifested in the chloroplast redox oscillations-characterized by diel hyperoxidation/reduction cycles of 2-Cys Peroxiredoxins-and the nuclear transcription/translation feedback loop (TTFL) machinery within plant cells, demonstrates a remarkable temporal coherence. However, the molecular mechanisms underlying the integration of these circadian rhythms remain elusive. Here, we elucidate that the chloroplast redox protein, NADPH-dependent thioredoxin reductase type-C (NTRC), modulates the integration of the chloroplast redox rhythms and nuclear circadian clocks by regulating intracellular levels of reactive oxygen species and sucrose. In NTRC-deficient ntrc mutants, the perturbed temporal dynamics of cytosolic metabolite pools substantially attenuated the amplitude of CIRCADIAN CLOCK ASSOCIATED-1 (CCA1) mRNA oscillation, while maintaining its inherent periodicity. In contrast, these fluctuations extended the period and ameliorated the amplitude of GIGANTEA (GI). In alignment with its regulatory role, the chloroplast redox rhythm and TTFL-driven nuclear oscillators are severely disrupted in ntrc plants. The impairments are rescued by NTRC expression, but not by the catalytically inactive NTRC(C/S) mutant, indicating that NTRC's redox activity is essential for synchronizing intracellular circadian rhythms. In return, the canonical nuclear clock component, TIMING OF CAB EXPRESSION-1 (TOC1), regulates the diel chloroplast redox rhythm by controlling NTRC expression, as evidenced by the redox cycle of chloroplast 2-Cys Peroxiredoxins. This reciprocal regulation suggests a tight coupling between chloroplast redox rhythms and nuclear oscillators. Consequently, our research has successfully identified NTRC as a key circadian modulator, elucidating the intricate connection between the metabolite-dependent chloroplast redox rhythm and the temporal dynamics of nuclear canonical clocks.

Maize, a cornerstone of global food security, has undergone remarkable transformations through breeding, yet it faces mounting challenges in a changing world. In this review, we trace the historical successes of maize breeding which laid the foundation for present opportunities. We examine both the specific and shared breeding goals related to diverse geographies and end-use demands. Achieving these coordinated breeding objectives requires a holistic approach to trait improvement for sustainable agriculture. We discuss cutting-edge solutions, including multi-omics approaches from single-cell analysis to holobionts, smart breeding with advanced technologies and algorithms, and the transformative potential of rational design with synthetic biology. A transition towards a data-driven future is currently underway, with large-scale precision agriculture and autonomous systems poised to revolutionize farming practice. Realizing these futuristic opportunities hinges on collaborative efforts spanning scientific discoveries, technology translations, and socioeconomic considerations in maximizing human and environmental well-being.

Although numerous studies have focused on the specific organs or tissues at different development stages or under various abiotic and biotic stress, our understanding of the distribution and relative abundance of phytohormones throughout the entire life cycle of plant organs and tissues remains insufficient. Here, we present a phytohormone atlas resource covering the quantitative analysis of eight major classes of phytohormones, comprising a total of 40 hormone-related compounds, throughout the complete life cycle of wheat. In combination with transcriptome analysis, we established a Wheat Phytohormone Metabolic Regulatory Network (WPMRN). Using our WPMRN dataset and GO enrichment analysis, we swiftly characterized the function of TaLOG5-B1 in cytokinin biosynthesis. Furthermore, a detailed investigation of the WPMRN dataset uncovered transcription factor-mediated co-regulation mechanisms among different classes of phytohormones. We focused specifically on the metabolic regulatory involving cytokinin and jasmonic acid. To achieve this, we characterized genes TaLOG3-D1 and TaAOS-D1 involved in the biosynthesis of these phytohormones, along with their regulatory transcription factors TaDOF3A and TaDOF5.6B. The functions of these genes were validated in transgenic plants, revealing their ability to co-regulate radicle length. These findings serve as a case study that highlights the utility of this resource for studying phytohormone metabolic regulatory networks in cereal crops and for gaining insights into the roles of phytohormones in enhancing agronomic traits.

Hydrogen sulfide (H2S) is recognized as an important gaseous signaling molecule, similar to nitric oxide and carbon monoxide. However, the synthesis mechanism of H2S and its role in enhancing rice resistance to Xanthomonas oryzae pv. oryzicola (Xoc) and Xanthomonas oryzae pv. oryzae (Xoo) are less known. Our research identifies that H2S induces bursts of reactive oxygen species and upregulates defense-related genes in rice. However, excessive H2S concentrations inhibit rice growth. We further demonstrate that the cystathionine β-synthase, OsCBSX3, regulates rice growth and resistance to Xoc and Xoo by modulating H2S biosynthesis. OsCBSX3 exists in both oligomeric and monomeric forms in rice. Compared to the wild-type OsCBSX3, the oligomer-disrupting mutant exhibited a reduced capacity for H2S synthesis, diminished resistance to Xanthomonas oryzae, and an inability to localize to the chloroplast. Upon pathogen recognition, rice triggers PsbO-dependent oligomerization of OsCBSX3, leading to increased H2S production and enhanced defense responses. However, excessive concentrations of H2S reduce the oligomerized form of OsCBSX3, facilitating its dissociation from PsbO and its binding to OsTrxZ. OsTrxZ directly converts OsCBSX3 into monomers, thereby mitigating the excessive H2S synthesis and its negative effects on rice growth and development. OsTrxZ belongs to the thioredoxin family, and PsbO is an important subunit of photosystem II. Overexpression of PsbO enhances rice resistance to both Xoc and Xoo, whereas overexpression of OsTrxZ exerts the opposite effect. These findings suggest that PsbO and OsTrxZ antagonistically modulate the conversion between oligomeric and monomeric forms of OsCBSX3, thereby balancing rice resistance and developmental processes.

Plants are able to sense and remember heat stress. An initial priming heat stress enables plants to acclimate so that they are able to survive a subsequent higher temperature. The heatshock transcription factors (HSFs) play a crucial role in this process, but the mechanisms by which plants sense heat stress are not well understood. By comprehensively analyzing the binding targets of all the HSFs, we find that HSFs act in a network, with upstream sensory acting in a transcriptional cascade to activate downstream HSFs and protective proteins. The upstream sensory HSFs are activated by heat at the protein level via a modular Prion-like Domain (PrD) structure. PrD1 enables HSF sequestration via chaperone binding, allowing release under heatshock. Activated HSFs are recruited into transcriptionally active foci via PrD2, enabling the formation of DNA loops between heat responsive promoters and enhancer motifs, boosting gene expression days after a priming heat stress. The ability of HSFs to respond rapidly to heat via a protein phase change response is likely a conserved mechanism in eukaryotes.

Wheat (Triticum aestivum L.) production is vital for global food security, providing energy and protein to millions of people worldwide. Recent advancements in wheat research have led to significant increases in production, fueled by technological and scientific innovation. Here, we summarize the major advancements in wheat research, particularly the integration of biotechnologies and a deeper understanding of wheat biology. The shift from multi-omics to pan-omics approaches in wheat research has greatly enhanced our understanding of the complex genome, genomic variations, and regulatory networks to decode complex traits. We also outline key scientific questions, potential research directions, and technological strategies for improving wheat over the next decade. Since global wheat production is expected to increase by 60% in 2050, continued innovation and collaboration are crucial. Integrating biotechnologies and a deeper understanding of wheat biology will be essential in addressing future challenges in wheat production, ensuring sustainable practices and improved productivity.