The Actinorhizal Symbiosis

@article{Wall2000TheAS,
  title={The Actinorhizal Symbiosis},
  author={Luis Gabriel Wall},
  journal={Journal of Plant Growth Regulation},
  year={2000},
  volume={19},
  pages={167-182}
}
  • L. Wall
  • Published 1 June 2000
  • Biology
  • Journal of Plant Growth Regulation
A bstractThe term ``actinorhiza'' refers both to the filamentous bacteria Frankia, an actinomycete, and to the root location of nitrogen-fixing nodules. Actinorhizal plants are classified into four subclasses, eight families, and 25 genera comprising more than 220 species. Although ontogenically related to lateral roots, actinorhizal nodules are characterized by differentially expressed genes, supporting the idea of the uniqueness of this new organ. Two pathways for root infection have been… 

Actinorhizal symbioses : diversity and biogeography

The actinobacterial genus Frankia encompasses sporulating filamentous bacteria (actinomycetes) that fix N2; they are defined by their ability to induce N2-fixing root nodules on a broad range of

CHAPTER 7 – Actinorhizal symbioses

Molecular Methods for Research on Actinorhiza

TLDR
An inventory of the main recent molecular tools and techniques developed for studying actinorhizae is reported, mainly linked to the woody nature of the plant species and the lack of genetic tools for their bacterial symbionts.

Induction of Actinorhizal Nodules by Frankia

TLDR
An overview of infection mechanisms and nodule structure is given; comparisons with the corresponding mechanisms in legume–rhizobia symbioses are presented.

Establishment of Actinorhizal Symbioses

TLDR
This chapter summarises the current knowledge of the signalling mechanisms and cellular events that occur during the establishment of actinorhizal symbioses, and describes what is known about the signal exchanges occurring prior to infection.

Actinorhizal nitrogen fixing nodules: infection process, molecular biology and genomics

TLDR
With progress in plant genome sequencing, comparative genomics in legumes and actinorhizal plants should contribute to the understanding of the evolutionary history of nitrogen-fixing symbioses.

Composite Actinorhizal Plants with Transgenic Roots for the Study of Symbiotic Associations with Frankia

TLDR
A gene transfer system based on Agrobacterium rhizogenes that opens the possibility to rapidly analyze the function of candidate symbiotic genes is reviewed and the potential of this technique to advancing the understanding of the molecular mechanisms underlying infection by Frankia is demonstrated by functional analyses of symbiosis genes.

Biology of the Frankia-Alnus maritima subsp. maritima symbiosis

TLDR
If nitrogen fixation is sustained under unfavorable conditions, woody plants that associate with nitrogenfixing organisms may show enhanced tolerance of environmental stress; species of plants capable of nitrogen-fixing symbioses are known to have comparatively strong resistance to invasion by pathogens.

Transformed Hairy Roots of the actinorhizal shrub Discaria trinervis: a valuable tool for studying actinorhizal symbiosis in the context of intercellular infection

TLDR
To decipher the molecular mechanisms underlying intercellular infection with Frankia, this work set up an efficient genetic transformation protocol for D. trinervis based on A. rhizogenes, an actinorhizal shrub belonging to the Rosales order.

Signalling in actinorhizal root nodule symbioses

TLDR
This review provides an outline on signalling molecules involved at different stages of actinorhizal nodule formation and the corresponding signalling pathways and gene networks.
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TLDR
Sufficient information about the relationship of Frankia strains to other bacteria, and to each other, is now available to warrant the creation of some species based on phenotypic and genetic criteria.

Actinorhizal Symbioses : Recent Advances in Plant Molecular and Genetic Transformation Studies

TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
The findings indicate that prenodules represent primitive symbiotic organs whose cell types display the same characteristics as their nodule counterparts, and are discussed in the context of the evolution of root nodule symbioses.
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