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Nature Dec 1947
Topics: Animals; Humans; Neoplasms; Plant Tumors; Plants
PubMed: 20272986
DOI: 10.1038/160780a0 -
Phytopathology Apr 2023The phytopathogenic bacterium causes crown gall disease in plants, characterized by the formation of tumor-like galls where wounds were present. Nowadays, however, the... (Review)
Review
The phytopathogenic bacterium causes crown gall disease in plants, characterized by the formation of tumor-like galls where wounds were present. Nowadays, however, the bacterium and its Ti (tumor-inducing) plasmid is better known as an effective vector for the genetic manipulation of plants and fungi. In this review, I will briefly summarize some of the major discoveries that have led to this bacterium now playing such a prominent role worldwide in plant and fungal research at universities and research institutes and in agricultural biotechnology for the production of genetically modified crops. I will then delve a little deeper into some aspects of biology and discuss the diversity among agrobacteria and the taxonomic position of these bacteria, the diversity in Ti plasmids, the molecular mechanism used by the bacteria to transform plants, and the discovery of protein translocation from the bacteria to host cells as an essential feature of -mediated transformation.
Topics: Plant Tumor-Inducing Plasmids; Crops, Agricultural; Plant Diseases; Plants, Genetically Modified; Agrobacterium tumefaciens; Plant Tumors; Plasmids
PubMed: 37098885
DOI: 10.1094/PHYTO-11-22-0432-IA -
Journal of Insect Physiology Jan 2016Biologists who study insect-induced plant galls are faced with the overwhelming diversity of plant forms and insect species. A challenge is to find common themes amidst... (Review)
Review
Biologists who study insect-induced plant galls are faced with the overwhelming diversity of plant forms and insect species. A challenge is to find common themes amidst this diversity. We discuss common themes that have emerged from our cytological and histochemical studies of diverse neotropical insect-induced galls. Gall initiation begins with recognition of reactive plant tissues by gall inducers, with subsequent feeding and/or oviposition triggering a cascade of events. Besides, to induce the gall structure insects have to synchronize their life cycle with plant host phenology. We predict that reactive oxygen species (ROS) play a role in gall induction, development and histochemical gradient formation. Controlled levels of ROS mediate the accumulation of (poly)phenols, and phytohormones (such as auxin) at gall sites, which contributes to the new cell developmental pathways and biochemical alterations that lead to gall formation. The classical idea of an insect-induced gall is a chamber lined with a nutritive tissue that is occupied by an insect that directly harvests nutrients from nutritive cells via its mouthparts, which function mechanically and/or as a delivery system for salivary secretions. By studying diverse gall-inducing insects we have discovered that insects with needle-like sucking mouthparts may also induce a nutritive tissue, whose nutrients are indirectly harvested as the gall-inducing insects feeds on adjacent vascular tissues. Activity of carbohydrate-related enzymes across diverse galls corroborates this hypothesis. Our research points to the importance of cytological and histochemical studies for elucidating mechanisms of induced susceptibility and induced resistance.
Topics: Adaptation, Physiological; Animals; Host-Parasite Interactions; Insecta; Plant Cells; Plant Growth Regulators; Plant Tumors; Plants
PubMed: 26620152
DOI: 10.1016/j.jinsphys.2015.11.012 -
Zootaxa Jun 2016This large family is poorly known in Colombia, where only 44 species have been recorded in 20 genera. All of them are included in Cecidomyiinae, which is the most...
This large family is poorly known in Colombia, where only 44 species have been recorded in 20 genera. All of them are included in Cecidomyiinae, which is the most diverse subfamily of gall midges in number of species and feeding habits, including phytophagous, predaceous and fungivorous species. Most of them are galler. The other subfamilies have never been recorded in this country.
Topics: Animal Distribution; Animals; Catalogs as Topic; Chironomidae; Colombia; Ecosystem; Female; Male; Plant Tumors; Plants
PubMed: 27395254
DOI: 10.11646/zootaxa.4122.1.6 -
In Vitro Jan 1980Transformation of plant tissues into crown gall tumors has been associated with the transfer of a portion of a tumor-inducing plasmid (Ti-plasmid) into plant DNA....
Transformation of plant tissues into crown gall tumors has been associated with the transfer of a portion of a tumor-inducing plasmid (Ti-plasmid) into plant DNA. Various laboratories have regenerated normal-appearing plants from a number of crown gall tumors. This study investigates the fate of the foreign DNA in a series of tissues derived from various parts of a plant regenerated from the tumor BT-37 by Braum and his coworkers. It was found that all the foreign DNA sequences were lost from tissues that had lost all their tumorous traits; whereas the plasmid DNA sequences were still present in tissues that appeared normal but still exhibited tumorous traits when returned to tissue culture media. From these studies it would appear that the presence of the Ti-plasmid sequences in the plant DNA is required for the maintenance of the transformed state.
Topics: DNA; DNA, Neoplasm; Plant Tumors; Plasmids
PubMed: 7364453
DOI: 10.1007/BF02618202 -
Plant Physiology Nov 2003
Topics: Agrobacterium tumefaciens; DNA, Bacterial; Plant Cells; Plant Tumors; Plants; Transformation, Genetic
PubMed: 14612580
DOI: 10.1104/pp.103.032821 -
Annual Review of Microbiology 1981
Review
Topics: Arginine; Bacteriophages; Base Sequence; Genes, Bacterial; Indoleacetic Acids; Oxazines; Plant Tumors; Plasmids; Pseudomonas; Recombination, Genetic; Rhizobium; Transcription, Genetic
PubMed: 7027906
DOI: 10.1146/annurev.mi.35.100181.002531 -
Current Biology : CB Dec 2018Egan et al. introduce the reader to gall wasps, including a description of their life cycle and complex ecological interactions with host plants and natural enemies.
Egan et al. introduce the reader to gall wasps, including a description of their life cycle and complex ecological interactions with host plants and natural enemies.
Topics: Animals; Host-Parasite Interactions; Plant Physiological Phenomena; Plant Tumors; Plants; Symbiosis; Wasps
PubMed: 30562523
DOI: 10.1016/j.cub.2018.10.028 -
Planta Jul 2022Plant responds to Agrobacterium via three-layered immunity that determines its susceptibility or resistance to Agrobacterium infection. Agrobacterium tumefaciens is a... (Review)
Review
Plant responds to Agrobacterium via three-layered immunity that determines its susceptibility or resistance to Agrobacterium infection. Agrobacterium tumefaciens is a soil-borne Gram-negative bacterium that causes crown gall disease in plants. The remarkable feat of interkingdom gene transfer has been extensively utilised in plant biotechnology to transform plant as well as non-host systems. In the past two decades, the molecular mode of the pathogenesis of A. tumefaciens has been extensively studied. Agrobacterium has also been utilised as a premier model to understand the defence response of plants during plant-Agrobacterium interaction. Nonetheless, the threat of Agrobacterium-mediated crown gall disease persists and is associated with a huge loss of plant vigour in agriculture. Understanding the molecular dialogues between these two interkingdom species might provide a cure for crown gall disease. Plants respond to A. tumefaciens by mounting a three-layered immune response, which is manipulated by Agrobacterium via its virulence effector proteins. Comparative studies on plant defence proteins versus the counter-defence of Agrobacterium have shed light on plant susceptibility and tolerance. It is possible to manipulate a plant's immune system to overcome the crown gall disease and increase its competence via A. tumefaciens-mediated transformation. This review summarises the recent advances in the molecular mode of Agrobacterium pathogenesis as well as the three-layered immune response of plants against Agrobacterium infection.
Topics: Agrobacterium tumefaciens; Plant Tumors; Plants; Virulence
PubMed: 35819629
DOI: 10.1007/s00425-022-03951-x -
Molecular Plant-microbe Interactions :... Mar 2017In this review, the wisdom and efficacy of studies seeking disease attenuating microbes and microbiomes only in healthy plant communities is questioned and an... (Review)
Review
In this review, the wisdom and efficacy of studies seeking disease attenuating microbes and microbiomes only in healthy plant communities is questioned and an alternative view is posited, namely that success in biocontrol of crop diseases may also come from studies of microbiota, or at least individual species isolates, associated with diseased plants. In support of this view, I summarize the current extensive knowledge of the biology behind what is probably the most successful biocontrol of a plant disease, namely the biocontrol of crown gall of stone fruit using non-pathogenic Rhizobium rhizogenes K84, in which the biocontrol agent itself came from a diseased plant.
Topics: Biological Control Agents; Microbiota; Plant Diseases; Plant Tumors; Plants
PubMed: 28051350
DOI: 10.1094/MPMI-12-16-0252-CR