This Article Full Text Full Text (PDF) Supplemental Data All Versions of this Article: 20/5/1407    most recent tpc.108.059014v1 Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Web of Science (19) Citing Articles via Google Scholar Google Scholar Articles by Genre, A. Articles by Bonfante, P. Search for Related Content PubMed PubMed Citation Articles by Genre, A. Articles by Bonfante, P. Agricola Articles by Genre, A. Articles by Bonfante, P.

Prepenetration Apparatus Assembly Precedes and Predicts the Colonization Patterns of Arbuscular Mycorrhizal Fungi within the Root Cortex of Both Medicago truncatula and Daucus carota^[W]

^a Department of Plant Biology, University of Turin, Istituto Protezione Piante–Consiglio Nazionale delle Ricerche, 10125 Turin, Italy
^b Laboratory of Plant-Microbe Interactions, Unité Mixte de Recherche, Institut National de la Recherche Agronomique–Centre National de la Recherche Scientifique 441/2594, F-31320 Castanet Tolosan, France

¹ Address correspondence to p.bonfante{at}ipp.cnr.it.

Arbuscular mycorrhizas (AM) are widespread, ancient endosymbiotic associations that contribute significantly to soil nutrient uptake in plants. We have previously shown that initial fungal penetration of the host root is mediated via a specialized cytoplasmic assembly called the prepenetration apparatus (PPA), which directs AM hyphae through the epidermis (Genre et al., 2005). In vivo confocal microscopy studies performed on Medicago truncatula and Daucus carota, host plants with different patterns of AM colonization, now reveal that subsequent intracellular growth across the root outer cortex is also PPA dependent. On the other hand, inner root cortical colonization leading to arbuscule development involves more varied and complex PPA-related mechanisms. In particular, a striking alignment of polarized PPAs can be observed in adjacent inner cortical cells of D. carota, correlating with the intracellular root colonization strategy of this plant. Ultrastructural analysis of these PPA-containing cells reveals intense membrane trafficking coupled with nuclear enlargement and remodeling, typical features of arbusculated cells. Taken together, these findings imply that prepenetration responses are both conserved and modulated throughout the AM symbiosis as a function of the different stages of fungal accommodation and the host-specific pattern of root colonization. We propose a model for intracellular AM fungal accommodation integrating peri-arbuscular interface formation and the regulation of functional arbuscule development.

This article has been cited by other articles:

				M. C. Baier, M. Keck, V. Godde, K. Niehaus, H. Kuster, and N. Hohnjec Knockdown of the Symbiotic Sucrose Synthase MtSucS1 Affects Arbuscule Maturation and Maintenance in Mycorrhizal Roots of Medicago truncatula Plant Physiology, February 1, 2010; 152(2): 1000 - 1014. [Abstract] [Full Text] [PDF]

				N. Pumplin and M. J. Harrison Live-Cell Imaging Reveals Periarbuscular Membrane Domains and Organelle Location in Medicago truncatula Roots during Arbuscular Mycorrhizal Symbiosis Plant Physiology, October 1, 2009; 151(2): 809 - 819. [Abstract] [Full Text] [PDF]

				M. Guether, B. Neuhauser, R. Balestrini, M. Dynowski, U. Ludewig, and P. Bonfante A Mycorrhizal-Specific Ammonium Transporter from Lotus japonicus Acquires Nitrogen Released by Arbuscular Mycorrhizal Fungi Plant Physiology, May 1, 2009; 150(1): 73 - 83. [Abstract] [Full Text] [PDF]

				A. Genre, G. Ortu, C. Bertoldo, E. Martino, and P. Bonfante Biotic and Abiotic Stimulation of Root Epidermal Cells Reveals Common and Specific Responses to Arbuscular Mycorrhizal Fungi Plant Physiology, March 1, 2009; 149(3): 1424 - 1434. [Abstract] [Full Text] [PDF]

				K. Yano, S. Yoshida, J. Muller, S. Singh, M. Banba, K. Vickers, K. Markmann, C. White, B. Schuller, S. Sato, et al. From the Cover: CYCLOPS, a mediator of symbiotic intracellular accommodation PNAS, December 23, 2008; 105(51): 20540 - 20545. [Abstract] [Full Text] [PDF]

				J. Fournier, A. C.J. Timmers, B. J. Sieberer, A. Jauneau, M. Chabaud, and D. G. Barker Mechanism of Infection Thread Elongation in Root Hairs of Medicago truncatula and Dynamic Interplay with Associated Rhizobial Colonization Plant Physiology, December 1, 2008; 148(4): 1985 - 1995. [Abstract] [Full Text] [PDF]