Effector(s) from filamentous pathogens that affect plant growth pattern

GEORGINA FABRO

Halle

Seminario; BPI Seminars at IPB, Halle.; 2020

Department of Biotic Plant Interactions, Leibniz Institute of Plant Biochemistry, Halle, Alemania

Different phytopathogens such as bacteria, fungi and oomycetes that feed on plants use a variety of molecules to colonize their hosts. ?Effector" proteins, which are secreted by pathogens and delivered into plant cells, play pivotal roles in establishing a successful infection. The detailed study of the activities exhibited by phytopathogen effectors is of great relevance for the generation of knowledge that allows improvement of crop resistance to pests, as well as to manipulate the biochemistry and the development of the plants in the absence of disease. In the latter case, knowing the function of the effectors would permit us to use their activities to modify for example; the transport of components to subcellular or extracellular domains, alter hormonal balances to promote growth, activate the transcription of specific defence genes in response to the perception of conserved pathogenic molecules, etc. A limitation for this type of applications is that very little is known about the roles of effectors themselves as well as the identities of their target proteins in the host cell and also the functions exerted by those targets when alone/modified by the effector. To contribute to this point, my current line of research is focused on characterizing the roles of RxLR effector proteins from the oomycete model pathogen Hyaloperonospora arabidopsidis (Hpa) -and their orthologs from Phytophthora infestans as well as effectors from the fungus Golovinomyces orontii - over the plant defence systems and their growth and development programs. Specifically, I am studying the interaction between the nuclear-localized effector HaRxL106 of Hpa and the transcription factors BIM1 and IAA11 involved in the brassinosteroid (BRs) and auxin hormonal pathways signalling in Arabidopsis. These plant proteins are also targets of a G. orontii effector, creating an opportunity to investigate how and why effectors from different kingdoms (oomyces and fungi) target the same host proteins.