Rust fungi include many species that are devastating crop pathogens. To develop resistant plants, a better understanding of rust virulence factors, or effector proteins, is needed. Thus far, only six rust effector proteins have been described: AvrP123, AvrP4, AvrL567, AvrM, RTP1, and PGTAUSPE-10-1. Although some are well established model proteins used to investigate mechanisms of immune receptor activation (avirulence activities) or entry into plant cells, how they work inside host tissues to promote fungal growth remains unknown. The genome sequences of four rust fungi (two Melampsoraceae and two Pucciniaceae) have been analyzed so far. Genome-wide analyses of these species, as well as transcriptomics performed on a broader range of rust fungi, revealed hundreds of small secreted proteins considered as rust candidate secreted effector proteins (CSEPs). The rust community now needs high-throughput approaches (effectoromics) to accelerate effector discovery/characterization and to better understand how they function in planta. However, this task is challenging due to the non-amenability of rust pathosystems (obligate biotrophs infecting crop plants) to traditional molecular genetic approaches mainly due to difficulties in culturing these species in vitro. The use of heterologous approaches should be promoted in the future.
Keywords: Pucciniales, rust fungi, genomics, transcriptomics, effectoromics
Citation: Petre B, Joly DL and Duplessis S (2014) Effector proteins of rust fungi. Front. Plant Sci. 5:416. doi: 10.3389/fpls.2014.00416
Received: 21 June 2014; Accepted: 04 August 2014;
Published online: 20 August 2014.
Edited by:Ken Shirasu, University of California, Davis, USA
Reviewed by:Ralf Thomas Voegele, Universität Hohenheim, Germany
Copyright © 2014 Petre, Joly and Duplessis. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
*Correspondence: Sébastien Duplessis, INRA, UMR 1136 Interactions Arbres/Microorganismes, Centre INRA Nancy Lorraine, Champenoux 54280, France e-mail: firstname.lastname@example.org