Author
Liam Dolan
Other affiliations: University of Pennsylvania, John Innes Centre, Gregor Mendel Institute ...read more
Bio: Liam Dolan is an academic researcher from University of Oxford. The author has contributed to research in topics: Root hair & Arabidopsis. The author has an hindex of 61, co-authored 175 publications receiving 16339 citations. Previous affiliations of Liam Dolan include University of Pennsylvania & John Innes Centre.
Papers published on a yearly basis
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TL;DR: It is shown here that RHD2 is an NADPH oxidase, a protein that transfers electrons from NADPH to an electron acceptor leading to the formation of reactive oxygen species (ROS) and that ROS accumulate in growing wild-type (WT) root hairs but their levels are markedly decreased in rhd2 mutants.
Abstract: Cell expansion is a central process in plant morphogenesis, and the elongation of roots and root hairs is essential for uptake of minerals and water from the soil. Ca2+ influx from the extracellular store is required for (and sets the rates of) cell elongation in roots. Arabidopsis thaliana rhd2 mutants are defective in Ca2+ uptake and consequently cell expansion is compromised--rhd2 mutants have short root hairs and stunted roots. To determine the regulation of Ca2+ acquisition in growing root cells we show here that RHD2 is an NADPH oxidase, a protein that transfers electrons from NADPH to an electron acceptor leading to the formation of reactive oxygen species (ROS). We show that ROS accumulate in growing wild-type (WT) root hairs but their levels are markedly decreased in rhd2 mutants. Blocking the activity of the NADPH oxidase with diphenylene iodonium (DPI) inhibits ROS formation and phenocopies Rhd2-. Treatment of rhd2 roots with ROS partly suppresses the mutant phenotype and stimulates the activity of plasma membrane hyperpolarization-activated Ca2+ channels, the predominant root Ca2+ acquisition system. This indicates that NADPH oxidases control development by making ROS that regulate plant cell expansion through the activation of Ca2+ channels.
2,098 citations
TL;DR: The anatomy of the developing root of Arabidopsis is described using conventional histological techniques, scanning and transmission electron microscopy and a model of meristem activity is proposed, which underpins future work on the developmental genetics of root morphogenesis.
Abstract: The anatomy of the developing root of Arabidopsis is described using conventional histological techniques, scanning and transmission electron microscopy. The root meristem is derived from cells of the hypophysis and adjacent cells of the embryo proper. The postembryonic organization of the root is apparent in the mature embryo and is maintained in the growing primary root after germination. Cell number and location is relatively invariant in the primary root, with 8 cortical and endodermal cell files but more variable numbers of pericycle and epidermal cells. The organisation of cells in lateral roots is similar to that of the primary root but with more variability in the numbers of cell files in each layer. [3H]thymidine labeling of actively growing roots indicates that a quiescent centre of four central cells (derived from the hypophysis) is located between the root cap columella and the stele. This plate of four cells is surrounded by three groups of cells in, proximal, distal and lateral positions. The labeling patterns of these cells suggest that they are the initials for the files of cells that comprise the root. They give rise to four sets of cell files: the stele, the cortex and endodermis, the epidermis and lateral root-cap and the columella. A model of meristem activity is proposed based on these data. This description of Arabidopsis root structure underpins future work on the developmental genetics of root morphogenesis.
1,344 citations
University of Oxford1, World Animal Protection2, University of Cambridge3, University of East Anglia4, University of Leeds5, Oxfam6, Food and Agriculture Organization7, University of British Columbia8, Commonwealth Scientific and Industrial Research Organisation9, University of Aberdeen10, CGIAR11, International Institute for Environment and Development12
TL;DR: Clearer understanding is needed of the premises underlying SI and how it relates to food-system priorities and climate change poses challenges to agriculture.
Abstract: Food security is high on the global policy agenda. Demand for food is increasing as populations grow and gain wealth to purchase more varied and resource-intensive diets. There is increased competition for land, water, energy, and other inputs into food production. Climate change poses challenges to agriculture, particularly in developing countries ( 1 ), and many current farming practices damage the environment and are a major source of greenhouse gases (GHG). In an increasingly globalized world, food insecurity in one region can have widespread political and economic ramifications ( 2 ).
1,309 citations
Monash University1, Kyoto University2, Kindai University3, United States Department of Energy4, Kobe University5, National Institute of Genetics6, Austrian Academy of Sciences7, Nara Institute of Science and Technology8, University of Osnabrück9, Universidad Veracruzana10, University of Cambridge11, CINVESTAV12, University of Oxford13, University of Tennessee14, Plant & Food Research15, Uppsala University16, Institut de recherche pour le développement17, University of Zurich18, University of Tokyo19, Nagoya University20, Okayama University21, National Institutes of Natural Sciences, Japan22, Tohoku University23, University of Kentucky24, Gregor Mendel Institute25, Tokyo University of Agriculture26, National Taiwan University27, Cold Spring Harbor Laboratory28, Autonomous University of Madrid29, University of Arizona30, Max Planck Society31, Tokyo Metropolitan University32, University of Minnesota33, Kumamoto University34, University of Ulm35, Saitama University36
TL;DR: Compared with other sequenced land plants, M. polymorpha exhibits low genetic redundancy in most regulatory pathways, with this portion of its genome resembling that predicted for the ancestral land plant.
774 citations
TL;DR: Evidence that supports the role of ROS in cell growth and spatial regulation of ROS production is an important factor controlling plant form is reviewed.
Abstract: Reactive oxygen species (ROS) are emerging as important regulators of plant development. There is now abundant evidence that ROS play roles in cell growth and that spatial regulation of ROS production is an important factor controlling plant form. Here we will review evidence that supports a role
493 citations
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TL;DR: The biochemistry of ROS and their production sites, and ROS scavenging antioxidant defense machinery are described, which protects plants against oxidative stress damages.
8,259 citations
TL;DR: This review summarizes the current state of knowledge of the functions of NOX enzymes in physiology and pathology.
Abstract: For a long time, superoxide generation by an NADPH oxidase was considered as an oddity only found in professional phagocytes. Over the last years, six homologs of the cytochrome subunit of the phag...
5,873 citations
TL;DR: In Arabidopsis, a network of at least 152 genes is involved in managing the level of ROS, and this network is highly dynamic and redundant, and encodes ROS-scavenging and ROS-producing proteins.
4,902 citations
Harvard University1, Stockholm Resilience Centre2, Potsdam Institute for Climate Impact Research3, University of Oxford4, City University London5, Chatham House6, World Wide Fund for Nature7, Environmental Change Institute8, University of Minnesota9, University of California, Santa Barbara10, CGIAR11, Johns Hopkins University12, American University of Beirut13, Wageningen University and Research Centre14, Institute for Health Metrics and Evaluation15, Indian Institute of Technology Kanpur16, ETH Zurich17, Commonwealth Scientific and Industrial Research Organisation18, University of Indonesia19, World Health Organization20, Food and Agriculture Organization21, International Food Policy Research Institute22, Royal Swedish Academy of Sciences23, University of Auckland24, Public Health Foundation of India25, Centre for Science and Environment26
TL;DR: Food in the Anthropocene : the EAT-Lancet Commission on healthy diets from sustainable food systems focuses on meat, fish, vegetables and fruit as sources of protein.
4,710 citations
TL;DR: Recent advances in elucidating the role of root exudates in interactions between plant roots and other plants, microbes, and nematodes present in the rhizosphere are described.
Abstract: The rhizosphere encompasses the millimeters of soil surrounding a plant root where complex biological and ecological processes occur. This review describes recent advances in elucidating the role of root exudates in interactions between plant roots and other plants, microbes, and nematodes present in the rhizosphere. Evidence indicating that root exudates may take part in the signaling events that initiate the execution of these interactions is also presented. Various positive and negative plant-plant and plant-microbe interactions are highlighted and described from the molecular to the ecosystem scale. Furthermore, methodologies to address these interactions under laboratory conditions are presented.
3,674 citations