Exosome components are altered in transgenic tobacco plants that co-express CP and MP viral proteins from TMV

CONTI, G; ASURMENDI, S

Potrero de los Funes, San Luis

Congreso; XLVII Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2011

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular

Viral diseases induce metabolic and physiological alterations probably associated to symptoms. Here we used transgenic plants that express TMV proteins to study the effect of each one on host gene expression. We studied the effects of capsid (CP) and movement protein (MP) and both CP and MP co-expression in tobacco. Neither CP nor MP exhibit silencing suppression effects, although plants that co-express them show altered levels of microRNAs and exhibit developmental changes that resemble symptoms. Gene expression patterns were analysed with a tomato 10K Affymetrix chip between CPxMP (altered phenotype) and cpxmp (silenced line with normal phenotype). We found many differentially expressed genes related to RNA turnover. In plants, this process is important for development and is rendered among others, by the exosome complex. We determined Rrp41, Rrp42 and Rrp43 expression levels (core subunits) in transgenic and TMV infected plants. We showed that GFP transient expression in CPxMP is enhanced, suggesting a modulation of transgene silencing in these plants. We silenced the expression of Rrp42 by means of VIGS in N. benthamiana and observed growth arrest, morphological defects and changes in miR156, miR164 and miR165 accumulation. Altogether, these data suggest that exosome components could be implicated in miRNAs alteration and symptom generation during plant-virus interaction.