INNATE IMMUNE GENES ARE DIFFERENTIALLY EXPRESSED IN TMV RESISTANT CP-MP TRANSGENIC PLANTS

CONTI, G; MANACORDA, CA; BAZZINI, AA; DI RIENZO, J; ASURMENDI, S

Carlos Paz - Prov. Córdoba - Argentina

Congreso; XLIV Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2008

Sociedad Argentina de Investigación Bioquímica

Viral diseases produced considerable economic losses worldwide. It is necessary to find new genetic strategies to obtain resistant crops. Transgenic co-expression of TMV movement protein (MP) and a mutated capside protein (CPm) in Nicotiana tabacum confers resistance to viral infections along with developmental defects, some of them similar to the symptoms produced by the infection. These plants also have increased levels of a set of microRNAs that produce similar phenotypes when overexpressed. To determine differences in gene expression between transgenic and control plants, we used a Tomato Affymetrix microarray chip. After statistical data analysis we selected 26 genes, 8 upregulated and 18 downregulated in transgenic plants. Bioinformatics analysis showed that some of these genes seem to be regulatory members of innate immune response; some are inhibitors of SAR (downregulated in transgenic plants) and other enhancers (upregulated). Another upregulated group of genes belonged to the RNA processing machinery, and there were also putative transcriptional factors and carbon metabolism related genes. These candidates are being validated by qRT-PCR. The complexity of immune response and its relation to development and growth are tightly regulated in plants. MicroRNAs could be involved in this regulation and consequently play a role in viral resistance.