Importance of vesicle trafficking in the establichsment of a geminiviral infection

Abstract

Importance of vesicle trafficking in the establishment of a geminiviral infection P. CANA-QUIJADA1, T. ROSAS-DÍAZ2, LOZANO-DURÁN R. 2 AND E.R. BEJARANO1 1Dpto. Biología Celular, Genética y Fisiología. Área de Genética Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora” (IHSM-UMA-CSIC), Universidad de Málaga, Málaga, Spain E-mail: pepecana@uma.es 2. Shanghai Center for Plant Stress Biology (PSC), Shanghai Institutes of Biological Sciences, Chinese Academy of Sciences, Shanghai 201602, China. INTRODUCTION Geminiviruses produces some of the most devastating diseases for agriculture worldwide. Geminiviral genomes encode only 5 to 7 proteins, forcing them to rely heavily on host cellular machineries and to interact with a high amount of host proteins in order to complete a full infection. The identification of the host proteins involved in viral infection will be an important step towards the understanding of the mechanisms underlying this process and develop new strategies to generate new sources of resistance. Previous efforts from our group have identified several genes involved in vesicle trafficking. OBJECTIVES The main aim of this work is to elucidate the role of the plant cell’s vesicle trafficking in a geminiviral infection. MATHERIALS AND METHODS Transgenic Nicotiana benthamiana plants containing a green fluorescent protein (GFP) expression cassette flanked by two direct repeats of the intergenic region of TYLCSV have been constructed (2IR plants). When these plants are infected with TYLCSV, an overexpression of the reporter gene is observed in those cells where the virus is actively replicating. 2IR plants were used in combination with virus induced gene silencing (VIGS), to identify vesicle trafficking genes involved in the infectious process. Viral replication was monitorized by GFP expression. Viral accumulation was determined using qPCR. RESULTS When silenced, four of the assessed genes reduced dramatically the viral amounts or completely abolished the infection. On the other hand, three of them had no significant effect over the infection and one of them seems to cause a slight increase in viral accumulation. CONCLUSIONS The vesicle trafficking machinery plays an essential role in geminivirus infection. Assays to determine whether the described effect is due to a lack of replication or movement of the virus inside the plant cells are in progress.