Plant Communications最新文献

Short summary: Seed germination of the parasitic plant Orobanche cumana is induced by host-derived strigolactones and dehydrocostus lactone. We show that the KAI2d2 receptor perceives both ligands through distinct modes of interaction. Triazole urea compounds covalently inhibit KAI2d receptors, suppressing germination without affecting sunflower growth.

Soils exhibit remarkable spatial heterogeneity in environmental conditions, which plants perceive at the levels of root system, individual roots, and root tissues. Cropping practices aimed at reducing the environmental footprint of agriculture are likely to intensify this heterogeneity, highlighting the urgent need to adapt crops to heterogenous soil environments. Recent advances in soil imaging and spatial omics offer unprecedented opportunities to decipher the molecular, physiological, and ecological processes that underpin plant-soil interactions. In this review, we explore the substantial yet largely untapped potential of integrating soil imaging with spatial omics to uncover the fundamental mechanisms controlling root foraging in heterogeneous soils. We present an overview of key imaging and molecular approaches with particular potential for revealing root foraging behaviours. To demonstrate their capabilities for generating spatially explicit insights into root-soil interactions, we highlight selected case studies covering both biotic (beneficial and detrimental soil organisms) and abiotic (physical and chemical soil properties) factors. Finally, we outline a workflow to integrate spatial omics with soil imaging through a vertical amalgamation of experimental studies across levels of environmental complexity, coupled with predictive modelling. To unlock the full potential of these approaches requires linking molecular, physiological, and ecological mechanisms at the root-soil interface to whole-plant growth and crop productivity. These fundamental insights into the edaphic drivers of root foraging will be essential for guiding crop adaptation to future, more heterogenous soil environments.

Anthocyanins and proanthocyanidins (PAs) are important flavonoids that have beneficial effects on plants and human health. Despite partially sharing a common biosynthetic pathway, these two flavonoids have a preference for tissue-specific accumulation in many fruits and plant organs. In tomato, anthocyanins are primarily accumulated in fruit peel of some wild relatives, while PAs are mainly accumulated in seeds. However, the underlying molecular mechanisms remain elusive. Here, we demonstrated that the tissue-specific accumulation of these two flavonoids in tomato fruits was achieved by different MYB-bHLH-WD40 (MBW) transcriptional modules. The bHLH transcription factor SlAN1 and the WD40 regulator SlAN11, critical components in the MBW complex, were required for both anthocyanin and PAs biosynthesis. By contrast, two MYB components of the MBW complex, SlAN2-like and SlMYB54, specifically regulated anthocyanins biosynthesis in peel and PAs biosynthesis in seeds, respectively. We further found that the two MYB components interacted with SlAN1 to form two competitive MBW transcriptional modules for tissue-specific accumulation of anthocyanins and PAs in tomato fruits. We also provided evidence supporting that the tissue-restricted accumulation pattern of anthocyanins and PAs in tomato fruit likely orchestrated a dual-layered protective mechanisms for successful seed dispersal. Our findings exemplified that the efficient biosynthesis of anthocyanins and PAs was attributed to the strict tissue-specific expression of both regulatory and functional genes, which provided a strategy to enhance anthocyanins and PAs levels in tomato fruits.

Cereal genomes have undergone repeated polyploidization and transposable element (TE) proliferation, collectively generating complex regulatory landscapes. The evolutionary trajectories and functional implications of these landscapes, however, remain largely unexplored. By employing chromatin-bound RNA sequencing across seven cereal species, we systematically mapped 45,952 regulatory element transcripts (RETs), including 32,867 distal RETs corresponding to enhancer RNAs (eRNAs). Our analysis reveals that 56% of lineage-specific eRNAs originate from TE expansions, suggesting TEs as significant reservoirs of species-specific regulatory innovation in cereals. Notably, we uncovered a remarkable similarity in defense-related function, root-specific expression, and TE-derived origin of eRNAs across ancient and recent evolutionary layers of Triticeae, suggesting recurrent recruitment of TE-derived root-associated regulatory elements during Triticeae evolution. Furthermore, we found that young eRNA pairs in hexaploid wheat with high sequence similarity, many originating from RLG_famc8.3 and DTC_famc4.3, exhibit pronounced root specificity and coordinated expression, suggesting a targeted amplification and refinement of the successful ancestral regulatory strategy established after Triticeae divergence. To facilitate community access, we developed Cereal-eRNAdb (http://bioinfo.cemps.ac.cn/Cereal-eRNAdb/), a comprehensive database integrating 69,426 eRNAs with functional annotations across 296 samples. Our work indicates that TE-mediated innovation of root-specific eRNAs as a candidate mechanism that may contribute to Triticeae adaptation and provides a foundational resource for exploiting regulatory variation in cereal crop breeding.

In angiosperms, male-female gamete interaction leads to double fertilization, yet the molecular mechanisms governing gamete interaction remain poorly understood. Through EMS mutagenesis, we identified two Arabidopsis mutants defective in sperm-egg fusion, both harboring mutation site in GAMETE INTERACTION PROTEIN 1 (GIP1)/GAMETE EXPRESSED 3 (GEX3). GIP1/GEX3 encodes a sperm-specific plasma membrane protein and its loss leads to severe fertility defects due to impaired double fertilization. Using a gip1-cr1 cdka;1 double mutant that produces pollen with a single sperm-like cell, we demonstrated that GIP1/GEX3 is required for the preferential fertilization of the egg cell. Further analysis revealed that GIP1/GEX3 functions at two distinct stages: gamete attachment and subsequent plasma membrane fusion. Importantly, we show that GIP1/GEX3 physically interacts with the sperm membrane protein GEX2 to regulate these two critical steps. Our work thus uncovers a key regulatory module mediating gamete attachment and plasma membrane fusion, providing new mechanistic insight into the control of double fertilization in flowering plants.

Double fertilization in angiosperms, a simultaneous fusion of sperm cells with the egg and central cells, requires precise gamete recognition and membrane fusion mediated by sperm cell surface proteins. However, the molecular regulation of these interactions remains incompletely understood. Here, we identify GEX3, a sperm-expressed transmembrane protein with an extracellular β-propeller domain, as a critical mediator of gamete adhesion and fusion. Loss of GEX3 disrupts fertilization by impairing sperm attachment to and fusion with female gametes. GEX3 physically and genetically interacts with GEX2 and DMP8/9 to promote the egg-cell-triggered trafficking of the fusogen HAP2/GCS1 to the sperm plasma membrane. Our findings establish GEX3 as an important component of the sperm cell surface machinery for coordinated membrane adhesion and fusion during double fertilization in flowering plants.

Carboxysomes are self-assembling proteinaceous microcompartments that encapsulate ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) and carbonic anhydrase within a semi-permeable shell, thereby elevating local CO₂ concentrations around Rubisco to improve carbon fixation. Their inherent design principles, including programmable architecture, cargo encapsulation, semi-permeability, and modular assembly, position carboxysomes as powerful paradigms in synthetic biology and bioengineering, offering unprecedented opportunities to boost carbon assimilation and unlock novel biotechnological functions. This review summarizes current knowledge of the molecular mechanisms of carboxysome structure, assembly, and function, and highlights key recent breakthroughs and key challenges such as achieving precise control of shell permeability and efficient cargo encapsulation, integrating carboxysomes into heterologous hosts. We also outline emerging strategies and future perspectives for engineering carboxysomes as enhanced CO₂-fixing engines and repurposing them as versatile nanomaterials in biotechnological applications. Together, these advances underscore the growing potential of carboxysome engineering to transform carbon-fixation pathways across diverse biological systems.

Plants utilize reactive oxygen species (ROS) as key defense signals, while pathogens evolve mechanisms to disrupt ROS homeostasis. However, plant factors that directly counter pathogen ROS-scavenging effectors remain elusive. Here, we identify the cysteine-rich receptor-like secreted protein 1 (OsCRRSP1) as a positive regulator of rice resistance to Magnaporthe oryzae. OsCRRSP1 expression is strongly induced upon infection, and genetic analyses show that knockout mutants are more susceptible, whereas overexpression enhances resistance. OsCRRSP1 directly interacts with and inhibits the H₂O₂-degrading activity of both the fungal catalase MoCatB and the rice catalase OsCatB, leading to reduced catalase activity and enhanced ROS accumulation. Consequently, OsCRRSP1 overexpression elevates H₂O₂ levels, whereas MoCatB overexpression suppresses ROS and promotes disease. These findings uncover a previously unrecognized OsCRRSP1-MoCatB/OsCatB module that fine-tunes ROS homeostasis to strengthen rice immunity and offers a promising molecular target for resistance breeding.