Comparative and functional genomics of phytoplasmas–emerging plant pathogens in Croatia

 

Team leder: Assist.Prof. Martina Šeruga Music

Abstract:

Phytoplasmas (genus 'Candidatus Phytoplasma') are wall-less bacteria from the class Mollicutes that affect numerous plant species worldwide causing significant economic losses. They have a unique life-style inhabiting plant phloem and insect cells and needing both hosts for survival and dispersal in nature. Their genomes are repeat-rich yet relatively small and reduced with many basic metabolic pathways missing. Phytoplasma axenic cultivation is still challenging. Nevertheless, four phytoplasma genomes have been completely sequenced and annotated with several genome drafts also available. However, the understanding of all mechanisms underlying phytoplasma pathogenicity is far from complete. First molecular evidence for the phytoplasma presence in Croatia has been given in late 1990’s on grapevine. Since then, the number of newly discovered phytoplasma species, insect vectors and affected plant hosts is constantly rising with grapevine and fruit trees’ phytoplasma pathosystems being well characterized. The main objective of this project would be sequencing of different isolates of ‘Ca. P. solani’, the most widespread phytoplasma in Croatia, with generation and comparative analysis of genome drafts or fully assembled genomes. Obtained results would give new data on candidate virulence effectors as well as other factors involved in interactions with hosts and adaptation to different environments. Another goal would be genotyping of new and already available isolates by multilocus sequence typing (MLST) analyses of different house-keeping and specific variable genes. New genotyping tools for improved diagnostics and molecular epidemiology studies with implications in risk assessment would also be developed. Functional studies would focus on surface variable membrane proteins involved in interactions with insect hosts and adaptation to diverse insect populations. Moreover, this would be the first sequencing project of a bacterial plant pathogen genome in Croatia. The establishment of this project and a research group would open a completely new field of molecular plant pathology and genomics, under-represented in Croatian science, and set a base for many subsequent studies.

 

Team Members:

Martina Šeruga Musić, Assist.Prof., Faculty of Science, University of Zagreb, Croatia
Dijana Škorić, Assoc. Prof., Faculty of Science, University of Zagreb, Croatia
Ivana Samaržija, PhD, Faculty of Science, University of Zagreb, Croatia
Saskia Hogenhout, Prof., PhD, John Innes Centre, UK
XavierFoissac, HDR, PhD, INRA - Centre de Bordeaux, France
Željko Budinšćak, PhD, Institute for Plant Protection, Croatian Centre for Agriculture, Food and Rural Affairs (IPP, CCAFRA), Croatia
Ivana Križanac, MSc, IPP, CCAFRA, Croatia
Jelena Plavec, PhD, IPP, CCAFRA, Croatia