Poster abstracts

Poster number 30 submitted by Laura de Lorenzo

Genome-wide analysis of alternative polyadenylation landscapes modulated during plant-pathogen interactions in Arabidopsis thaliana

Laura de Lorenzo (Department of Plant and Soil Sciences. University of Kentucky), Gah-Hyun Lim (Department of Plant Pathology. University of Kentucky), Pradeep Kachroo (Department of Plant Pathology. University of Kentucky), Arthur G. Hunt (Department of Plant and Soil Sciences. University of Kentucky)

Abstract:
In the past few years, several studies have highlighted significant roles of alternative polyadenylation (APA) in the control of physiological events such as cellular proliferation, differentiation, transformation, and organ development. This is true for APA events that lead to non-canonical mRNA isoforms (APA sites located in intron, 5’-UTR and coding regions), and affect the transcripts and their translation products. We hypothesized that alternative polyadenylation might also play an equally important role in regulation of host gene expression post pathogen infection in Arabidopsis. Using poly(A) site analysis coupled to high throughput sequencing, we examined polyadenylation events after bacterial, fungal and viral infections. This included both virulent and avirulent combination of bacterial [Pseudomonas syringae (Pst)] and viral [Turnip Crinkle Virus (TCV)] pathogens and a virulent isolate of necrotrophic fungal pathogen Botrytis cinerea. We found that virulent Pst and TCV infections led to an increase in the usage of non-canonical mRNA isoforms. Interestingly, avirulent response to Pst and TCV showed a general decrease in the production of non-canonical mRNA isoforms. Moreover, although APA profile changes after virulent infections were mainly associated with genes implicated in biotic and abiotic stress responses and electron transport, avirulent infections led to changes in genes encoding for receptor proteins and those implicated in signal transduction. Surprisingly, poly(A) site usage after Botrytis infection overlapped with that of the avirulent responses. A plasticity in transcription factors in APA genes expressed in any pathogen condition was also found. Together, these findings suggest that APA is induced in response to pathogen infection and might play an important role in fine-tuning of transcripts contributing to pathogen response.

References:
Supported by NSF Award 1243849

Keywords: Alternative polyadenylation, High throughput sequencing, Biotic stress