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The New Phytologist Jan 2018Contents Summary 62 I. Introduction 62 II. Plasmodesmal regulation is an innate defence response 63 III. Reactive oxygen species regulate plasmodesmal function 63 IV.... (Review)
Review
Contents Summary 62 I. Introduction 62 II. Plasmodesmal regulation is an innate defence response 63 III. Reactive oxygen species regulate plasmodesmal function 63 IV. Plasmodesmal regulation by and of defence-associated small molecules 64 V. Plasmodesmata facilitate systemic defence signalling 64 VI. Virulent pathogens exploit plasmodesmata 66 VII. Outlook 66 Acknowledgements 66 References 66 SUMMARY: Plasmodesmata (PD) are plasma membrane-lined pores that connect neighbouring plant cells, bridging the cell wall and establishing cytoplasmic and membrane continuity between cells. PD are dynamic structures regulated by callose deposition in a variety of stress and developmental contexts. This process crudely controls the aperture of the pore and thus the flux of molecules between cells. During pathogen infection, plant cells initiate a range of immune responses and it was recently identified that, following perception of fungal and bacterial pathogens, plant cells initially close their PD. Systemic defence responses depend on the spread of signals between cells, raising questions about whether PD are in different functional states during different immune responses. It is well established that viral pathogens exploit PD to spread between cells, but it has more recently been identified that protein effectors secreted by fungal pathogens can spread between host cells via PD. It is possible that many classes of pathogens specifically target PD to aid infection, which would infer antagonistic regulation of PD by host and pathogen. How PD regulation benefits both host immune responses and pathogen infection is an important question and demands that we examine the multicellular nature of plant-pathogen interactions.
Topics: Cell Membrane; Cell Wall; Cytoplasm; Glucans; Host-Pathogen Interactions; Plant Cells; Plant Immunity; Plants; Plasmodesmata; Reactive Oxygen Species; Signal Transduction
PubMed: 29083038
DOI: 10.1111/nph.14857 -
Current Biology : CB Dec 2018Multicellular organisms rely on cell-to-cell communication and resource exchange to coordinate the various diverse processes involved in growth, development, and...
Multicellular organisms rely on cell-to-cell communication and resource exchange to coordinate the various diverse processes involved in growth, development, and environmental responses across tissues and organs. Most complex multicellular organisms have highly organised and specialised anatomies, which develop by processes underpinned by regulated mechanisms for intercellular coordination. Indeed, in 1897 Wilhelm Pfeffer noted that for a plant to coordinate its physiological responses across the whole, there must be continuity throughout the entire organism, and that connections between cells must transport material and messages between tissues. Intercellular communication is an integral factor in any tissue-wide or organ-wide process in a multicellular organism.
Topics: Cell Membrane; Plant Physiological Phenomena; Plasmodesmata
PubMed: 30562524
DOI: 10.1016/j.cub.2018.11.004 -
Plants (Basel, Switzerland) Dec 2019Plant cells form a multicellular symplast via cytoplasmic bridges called plasmodesmata (Pd) and the endoplasmic reticulum (ER) that crosses almost all plant tissues. The... (Review)
Review
Plant cells form a multicellular symplast via cytoplasmic bridges called plasmodesmata (Pd) and the endoplasmic reticulum (ER) that crosses almost all plant tissues. The Pd proteome is mainly represented by secreted Pd-associated proteins (PdAPs), the repertoire of which quickly adapts to environmental conditions and responds to biotic and abiotic stresses. Although the important role of Pd in stress-induced reactions is universally recognized, the mechanisms of Pd control are still not fully understood. The negative role of callose in Pd permeability has been convincingly confirmed experimentally, yet the roles of cytoskeletal elements and many PdAPs remain unclear. Here, we discuss the contribution of each protein component to Pd control. Based on known data, we offer mechanistic models of mature leaf Pd regulation in response to stressful effects.
PubMed: 31842374
DOI: 10.3390/plants8120595 -
Virology May 2015Replication and intercellular spread of viruses depend on host mechanisms supporting the formation, transport and turnover of functional complexes between viral genomes,... (Review)
Review
Replication and intercellular spread of viruses depend on host mechanisms supporting the formation, transport and turnover of functional complexes between viral genomes, virus-encoded products and cellular factors. To enhance these processes, viruses assemble and replicate in membrane-associated complexes that may develop into "virus factories" or "viroplasms" in which viral components and host factors required for replication are concentrated. Many plant viruses replicate in association with the cortical ER-actin network that is continuous between cells through plasmodesmata. The replication complexes can be highly organized and supported by network interactions between the viral genome and the virus-encoded proteins. Intracellular PD targeting of replication complexes links the process of movement to replication and provides specificity for transport of the viral genome by the virus-encoded movement proteins. The formation and trafficking of replication complexes and also the development and anchorage of replication factories involves important roles of the cortical cytoskeleton and associated motor proteins.
Topics: Biological Transport; Cytoskeleton; Host-Pathogen Interactions; Plant Diseases; Plant Viral Movement Proteins; Plant Viruses; Virus Replication
PubMed: 25746797
DOI: 10.1016/j.virol.2015.01.025 -
International Journal of Molecular... May 2022Plasmodesmata (PD) are plant-specific channels connecting adjacent cells to mediate intercellular communication of molecules essential for plant development and defense.... (Review)
Review
Plasmodesmata (PD) are plant-specific channels connecting adjacent cells to mediate intercellular communication of molecules essential for plant development and defense. The typical PD are organized by the close apposition of the plasma membrane (PM), the desmotubule derived from the endoplasmic reticulum (ER), and spoke-like elements linking the two membranes. The plasmodesmal PM (PD-PM) is characterized by the formation of unique microdomains enriched with sphingolipids, sterols, and specific proteins, identified by lipidomics and proteomics. These components modulate PD to adapt to the dynamic changes of developmental processes and environmental stimuli. In this review, we focus on highlighting the functions of sphingolipid species in plasmodesmata, including membrane microdomain organization, architecture transformation, callose deposition and permeability control, and signaling regulation. We also briefly discuss the difference between sphingolipids and sterols, and we propose potential unresolved questions that are of help for further understanding the correspondence between plasmodesmal structure and function.
Topics: Cell Communication; Cell Membrane; Plasmodesmata; Sphingolipids; Sterols
PubMed: 35628487
DOI: 10.3390/ijms23105677 -
Plants (Basel, Switzerland) Mar 2018Communication between cells is an essential process for developing and maintaining multicellular collaboration during plant development and physiological adaptation in...
Communication between cells is an essential process for developing and maintaining multicellular collaboration during plant development and physiological adaptation in response to environmental stimuli. The intercellular movement of proteins and RNAs in addition to the movement of small nutrients or signaling molecules such as sugars and phytohormones has emerged as a novel mechanism of cell-to-cell signaling in plants. As a strategy for efficient intercellular communication and long-distance molecule movement, plants have evolved plant-specific symplasmic communication networks via plasmodesmata (PDs) and the phloem.
PubMed: 29558398
DOI: 10.3390/plants7010023 -
Plant Science : An International... Mar 2021Cell-to-cell communication is crucial in coordinating diverse biological processes in multicellular organisms. In plants, communication between adjacent cells occurs via... (Review)
Review
Cell-to-cell communication is crucial in coordinating diverse biological processes in multicellular organisms. In plants, communication between adjacent cells occurs via nanotubular passages called plasmodesmata (PD). The PD passage is composed of an appressed endoplasmic reticulum (ER) internally, and plasma membrane (PM) externally, that traverses the cell wall, and associates with the actin-cytoskeleton. The coordination of the ER, PM and cytoskeleton plays a potential role in maintaining the architecture and conductivity of PD. Many data suggest that PD-associated proteins can serve as tethers that connect these structures in a functional PD, to regulate cell-to-cell communication. In this review, we summarize the organization and regulation of PD activity via tethering proteins, and discuss the importance of PD-mediated cell-to-cell communication in plant development and defense against environmental stress.
Topics: Actins; Cell Membrane; Cell Wall; Endoplasmic Reticulum; Membrane Proteins; Plant Proteins; Plants; Plasmodesmata
PubMed: 33568299
DOI: 10.1016/j.plantsci.2020.110800 -
Cellular and Molecular Life Sciences :... Feb 2021Plasmodesmata are intercellular pores connecting together most plant cells. These structures consist of a central constricted form of the endoplasmic reticulum,... (Review)
Review
Plasmodesmata are intercellular pores connecting together most plant cells. These structures consist of a central constricted form of the endoplasmic reticulum, encircled by some cytoplasmic space, in turn delimited by the plasma membrane, itself ultimately surrounded by the cell wall. The presence and structure of plasmodesmata create multiple routes for intercellular trafficking of a large spectrum of molecules (encompassing RNAs, proteins, hormones and metabolites) and also enable local signalling events. Movement across plasmodesmata is finely controlled in order to balance processes requiring communication with those necessitating symplastic isolation. Here, we describe the identities and roles of the molecular components (specific sets of lipids, proteins and wall polysaccharides) that shape and define plasmodesmata structural and functional domains. We highlight the extensive and dynamic interactions that exist between the plasma/endoplasmic reticulum membranes, cytoplasm and cell wall domains, binding them together to effectively define plasmodesmata shapes and purposes.
Topics: Biological Transport; Cell Communication; Cell Wall; Cytoplasmic Structures; Endoplasmic Reticulum; Membrane Lipids; Plant Proteins; Plants; Plasmodesmata; Polysaccharides
PubMed: 32920696
DOI: 10.1007/s00018-020-03622-8 -
The Plant Genome Dec 2023As conserved regulatory agents, noncoding RNAs (ncRNAs) have an important impact on many aspects of plant life, including growth, development, and environmental... (Review)
Review
As conserved regulatory agents, noncoding RNAs (ncRNAs) have an important impact on many aspects of plant life, including growth, development, and environmental response. Noncoding RNAs can travel through not only plasmodesma and phloem but also intercellular barriers to regulate distinct processes. Increasing evidence shows that the intercellular trans-kingdom transmission of ncRNAs is able to modulate many important interactions between plants and other organisms, such as plant response to pathogen attack, the symbiosis between legume plants and rhizobia and the interactions with parasitic plants. In these interactions, plant ncRNAs are believed to be sorted into extracellular vesicles (EVs) or other nonvesicular vehicles to pass through cell barriers and trigger trans-kingdom RNA interference (RNAi) in recipient cells from different species. There is evidence that the features of extracellular RNAs and associated RNA-binding proteins (RBPs) play a role in defining the RNAs to retain in cell or secrete outside cells. Despite the few reports about RNA secretion pathway in plants, the export of extracellular ncRNAs is orchestrated by a series of pathways in plants. The identification and functional analysis of mobile small RNAs (sRNAs) are attracting increasing attention in recent years. In this review, we discuss recent advances in our understanding of the function, sorting, transport, and regulation of plant extracellular ncRNAs.
Topics: Gene-Environment Interaction; RNA Interference; RNA, Untranslated; RNA, Plant; Plants
PubMed: 36444889
DOI: 10.1002/tpg2.20289 -
Plants (Basel, Switzerland) May 2023Somatic embryogenesis (SE) is a process that scientists have been trying to understand for many years because, on the one hand, it is a manifestation of the totipotency... (Review)
Review
Somatic embryogenesis (SE) is a process that scientists have been trying to understand for many years because, on the one hand, it is a manifestation of the totipotency of plant cells, so it enables the study of the mechanisms regulating this process, and, on the other hand, it is an important method of plant propagation. Using SE in basic research and in practice is invaluable. This article describes the latest, but also historical, information on changes in the chemical composition of the cell wall during the transition of cells from the somatic to embryogenic state, and the importance of symplasmic communication during SE. Among wall chemical components, different pectic, AGP, extensin epitopes, and lipid transfer proteins have been discussed as potential apoplastic markers of explant cells during the acquisition of embryogenic competence. The role of symplasmic communication/isolation during SE has also been discussed, paying particular attention to the formation of symplasmic domains within and between cells that carry out different developmental processes. Information about the number and functionality of plasmodesmata (PD) and callose deposition as the main player in symplasmic isolation has also been presented.
PubMed: 37653868
DOI: 10.3390/plants12101951