Plant Physiol. Illumina
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
QUICK SEARCH:   [advanced]


     

Plant Physiology Preview
Published on February 2, 2007; 10.1104/pp.106.095356

OPEN ACCESS ARTICLE
This Article
Free via Open Access: OA
Right arrow Full Text (Plant Physiology Preview (PDF))
Right arrowOA All Versions of this Article:
143/3/1293    most recent
pp.106.095356v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Web of Science (8)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Kumagai, H.
Right arrow Articles by Kouchi, H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Kumagai, H.
Right arrow Articles by Kouchi, H.
Agricola
Right arrow Articles by Kumagai, H.
Right arrow Articles by Kouchi, H.

Received December 29, 2006
Accepted January 21, 2007

A Novel Ankyrin-repeat Membrane Protein IGN1 Is Required for Persistence of Nitrogen-fixing Symbiosis in Root Nodules of Lotus japonicus

Hirotaka Kumagai , Tsuneo Hakoyama , Yosuke Umehara , Shusei Sato , Takakazu Kaneko , Satoshi Tabata , and Hiroshi Kouchi *

National Institute of Agrobiological Sciences, 2-1-2 Kannondai, Tsukuba, Ibaraki 305-8602, Japan; Kazusa DNA Research Institute, 1532-3 Yana, Kisarazu, Chiba 292-0812, Japan

* Corresponding author; email: kouchih{at}nias.affrc.go.jp.

Nitrogen-fixing symbiosis of legume plants with Rhizobium bacteria is established through complex interactions between two symbiotic partners. Similar to the mutual recognition and interactions at the initial stages of symbiosis, nitrogen fixation activity of rhizobia inside root nodules of the host legume is also controlled by specific interactions during later stages of nodule development. We isolated a novel Fix- mutant, ign1 (ineffective greenish nodules), of Lotus japonicus, which forms apparently normal nodules containing endosymbiotic bacteria, but does not develop nitrogen fixation activity. Map-based cloning of the mutated gene allowed us to identify the IGN1 gene, which encodes a novel ankyrin-repeat protein with transmembrane regions. IGN1 expression was detected in all organs of L. japonicus, and not enhanced in the nodulation process. Immuno-analysis, together with expression analysis of a GFP-IGN1 fusion construct, demonstrated localization of the IGN1 protein in the plasma membrane. The ign1 nodules showed extremely rapid premature senescence. Irregularly enlarged symbiosomes with multiple bacteroids were observed at early stages (8-9 days post inoculation) of nodule formation, followed by disruption of the symbiosomes and disintegration of nodule infected cell cytoplasm with aggregation of the bacteroids. Although the exact biochemical functions of the IGN1 gene are still to be elucidated, these results indicate that IGN1 is required for differentiation and/or persistence of bacteroids and symbiosomes, thus being essential for functional symbiosis.




This article has been cited by other articles:


Home page
 MicrobiologyHome page
N. Ishmael, J. C. D. Hotopp, P. Ioannidis, S. Biber, J. Sakamoto, S. Siozios, V. Nene, J. Werren, K. Bourtzis, S. R. Bordenstein, et al.
Extensive genomic diversity of closely related Wolbachia strains
Microbiology, July 1, 2009; 155(7): 2211 - 2222.
[Abstract] [Full Text] [PDF]

Home page
 J Exp BotHome page
O. Schumpp, M. Crevecoeur, W. J. Broughton, and W. J. Deakin
Delayed maturation of nodules reduces symbiotic effectiveness of the Lotus japonicus-Rhizobium sp. NGR234 interaction
J. Exp. Bot., February 1, 2009; 60(2): 581 - 590.
[Abstract] [Full Text] [PDF]

Home page
 Plant CellHome page
K. Yokota, E. Fukai, L. H. Madsen, A. Jurkiewicz, P. Rueda, S. Radutoiu, M. Held, M. S. Hossain, K. Szczyglowski, G. Morieri, et al.
Rearrangement of Actin Cytoskeleton Mediates Invasion of Lotus japonicus Roots by Mesorhizobium loti
PLANT CELL, January 1, 2009; 21(1): 267 - 284.
[Abstract] [Full Text] [PDF]

Home page
 Plant CellHome page
T. Vernie, S. Moreau, F. de Billy, J. Plet, J.-P. Combier, C. Rogers, G. Oldroyd, F. Frugier, A. Niebel, and P. Gamas
EFD Is an ERF Transcription Factor Involved in the Control of Nodule Number and Differentiation in Medicago truncatula
PLANT CELL, October 1, 2008; 20(10): 2696 - 2713.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
ASPB Publications PLANT PHYSIOLOGY® THE PLANT CELL
Copyright © 2007 by the American Society of Plant Biologists