Proteomic profiling unravels insights into the molecular background underlying increased Aphanomyces euteiches-tolerance of Medicago truncatula

authored by

Frank Colditz, Hans Peter Braun, Christophe Jacquet, Karsten Niehaus, Franziska Krajinski

Abstract

To investigate the molecular mechanisms underlying susceptibility of legumes to the root pathogen Aphanomyces euteiches (oomycota), comparative proteomic studies have been carried out. In a first approach, we have analysed two Medicago truncatula lines of the French CORE collection (F83.005-5 (R2002) and F83.005-9 (R2002)), which showed either increased or decreased susceptibility to A. euteiches as compared to the widely adopted line A17. Several proteins were identified to be differentially induced after pathogen challenge in the two M. truncatula accessions with altered disease susceptibility, whereof proteins with increased abundances in the more resistant line F83.005-9 could be involved in mechanisms that lead to an improved disease resistance. Among these proteins, we identified two proteasome alpha subunits, which might be involved in defense response. To broaden our studies on A. euteiches-tolerance of M. truncatula, we investigated two other phenomena that lead to an either increased A. euteiches-resistance or to an enhanced susceptibility. The topic of an enhanced plant resistance to A. euteiches was studied in plants showing a bioprotective effect of a pre-established arbuscular mycorrhiza (AM) symbiosis. Evaluation of root fresh weights and pathogen spreading in the root system clearly indicate that mycorrhizal plants show increased A. euteiches-resistance as compared to non-mycorrhizal plants. Proteome analyses revealed the induction of similar protein patterns as in the M. truncatula accessions with comparatively high resistance level to A. euteiches. In a third approach, increased A. euteiches susceptibility was effected by exogenous abscisic acid (ABA) application prior to root infection. Evaluation of the abundance levels of a group of pathogenesis related class 10 (PR10)-like proteins, which were previously identified to be regulated after A. euteiches infection, revealed a correlation between the abundance levels of these proteins and the A. euteiches infection level or severity.

Organisation(s)

Institute of Plant Genetics

External Organisation(s)

Pôle de Biotechnologie Végétale
Bielefeld University

Type

Article

Journal

Plant molecular biology

Volume

59

Pages

387-406

No. of pages

20

ISSN

0167-4412

Publication date

10.2005

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Agronomy and Crop Science, Genetics, Plant Science

Electronic version(s)

https://doi.org/10.1007/s11103-005-0184-z (Access: Unknown)