Plant Physiology Preview Published on August 8, 2002; 10.1104/pp.003525
Received January 31, 2002
Returned for revision March 30, 2002
Accepted May 26, 2002
Differential Expression of a Metallothionein Gene during the Presymbiotic versus the Symbiotic Phase of an Arbuscular Mycorrhizal Fungus
Luisa Lanfranco , Angelo Bolchi , Emanuele Cesale Ros , Simone Ottonello , and Paola Bonfante *
Dipartimento di Biologia Vegetale, Università di Torino and Istituto per la Protezione delle Piante-Sezione di Torino, Consiglio Nazionale delle Ricerche, Viale Mattioli 25, 10125 Torino, Italy (L.L., E.C.R., P.B.); and Dipartimento di Biochimica e Biologia Molecolare, Università di Parma, Parco Area delle Scienze 23/A, 43100 Parma, Italy (A.B., S.O.)
* Corresponding author; email: p.bonfante{at}csmt.to.cnr.it.
A full-length cDNA encoding a metallothionein (MT)-like polypeptide, designated GmarMT1, was identified in an expressed sequence tag collection from germinated spores of the arbuscular mycorrhizal fungus Gigaspora margarita (BEG34). The GmarMT1 gene is composed of two exons separated by an 81-bp intron. It codes for a 65-amino acid polypeptide comprising a plant type 1 MT-like N-terminal domain and a C-terminal domain that is most closely related to an as-yet-uncharacterized fungal MT. As revealed by heterologous complementation assays in yeast, GmarMT1 encodes a functional polypeptide capable of conferring increased tolerance against Cd and Cu. The GmarMT1 RNA is expressed in both presymbiotic spores and symbiotic mycelia, even in the absence of metal exposure, but is significantly less abundant in the latter stage. An opposite pattern was observed upon Cu exposure, which up-regulated GmarMT1 expression in symbiotic mycelia but not in germinated spores. Together, these data provide the first evidence, to our knowledge, for the occurrence in an arbuscular mycorrhizal fungus of a structurally novel MT that is modulated in a metal and life cycle stage-dependent manner and may afford protection against heavy metals (and other types of stress) to both partners of the endomycorrhizal symbiosis.
This article has been cited by other articles:

|
 |

|
 |
 
G. Ramesh, G. K. Podila, G. Gay, R. Marmeisse, and M. S. Reddy
Different Patterns of Regulation for the Copper and Cadmium Metallothioneins of the Ectomycorrhizal Fungus Hebeloma cylindrosporum
Appl. Envir. Microbiol.,
April 15, 2009;
75(8):
2266 - 2274.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
T. Xue, X. Li, W. Zhu, C. Wu, G. Yang, and C. Zheng
Cotton metallothionein GhMT3a, a reactive oxygen species scavenger, increased tolerance against abiotic stress in transgenic tobacco and yeast
J. Exp. Bot.,
January 1, 2009;
60(1):
339 - 349.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
L. Lanfranco, M. Novero, and P. Bonfante
The Mycorrhizal Fungus Gigaspora margarita Possesses a CuZn Superoxide Dismutase That Is Up-Regulated during Symbiosis with Legume Hosts
Plant Physiology,
April 1, 2005;
137(4):
1319 - 1330.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. Courbot, L. Diez, R. Ruotolo, M. Chalot, and P. Leroy
Cadmium-Responsive Thiols in the Ectomycorrhizal Fungus Paxillus involutus
Appl. Envir. Microbiol.,
December 1, 2004;
70(12):
7413 - 7417.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
T. E. Pawlowska and I. Charvat
Heavy-Metal Stress and Developmental Patterns of Arbuscular Mycorrhizal Fungi
Appl. Envir. Microbiol.,
November 1, 2004;
70(11):
6643 - 6649.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. L. Tucker, C. R. Thornton, K. Tasker, C. Jacob, G. Giles, M. Egan, and N. J. Talbot
A Fungal Metallothionein Is Required for Pathogenicity of Magnaporthe grisea
PLANT CELL,
June 1, 2004;
16(6):
1575 - 1588.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
R. Ruotolo, A. Peracchi, A. Bolchi, G. Infusini, A. Amoresano, and S. Ottonello
Domain Organization of Phytochelatin Synthase: FUNCTIONAL PROPERTIES OF TRUNCATED ENZYME SPECIES IDENTIFIED BY LIMITED PROTEOLYSIS
J. Biol. Chem.,
April 9, 2004;
279(15):
14686 - 14693.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
P. Bonfante
Plants, Mycorrhizal Fungi and Endobacteria: a Dialog Among Cells and Genomes
Biol. Bull.,
April 1, 2003;
204(2):
215 - 220.
[Abstract]
[Full Text]
[PDF]
|
 |
|
|
|