RNA-SEQ BASED TRANSCRIPTOME ANALYSIS REVEALS UV-REGULATED GENE EXPRESSION IN A NATIVE ISOLATE OF AUREOBASIDIUM PULLULANS FROM PATAGONIA

MICAELA PARRA; LUCÍA ÁLVAREZ; CONSUELO OLIVARES-YAÑEZ; LORENA FRANCO; DIEGO LIBKIND; NICOLÁS BELLORA

San Carlos de Bariloche, Río Negro

Simposio; 34° International Specialized Symposium on Yeasts (34°ISSY); 2018

Ultravioletradiation (UVR) is an important harmful factor for biosphere,inducing several stress responses in organisms. The exposure to UVR-B(280?315 nm) can cause direct and indirect cellular damage. Fororganisms living in extreme conditions, daily exposure to UVR-B (?UV?from now on) acts as an environmental pressure, selecting strategiesto improve their performances against UV-detrimental effects, such asthe production of ROS. It is known that several species of fungi areable to produce mycosporines, a biotechnologically important moleculewith antioxidant and UV sunscreen activities. We predicted a genecluster potentially responsible for mycosporine biosynthesis in thegenome of Aureobasidiumpullulans. Thiscluster is similar to that reported in the genome of themycosporinogenic yeast Phaffiarhodozyma.The aim of this work was to characterize global changes in geneexpression induced by UV exposure in a native isolate of A.pullulansfrom Patagonia through a RNA-seq-based transcriptomic approach. Wecompared RNA-seq results for cultures grown at 20 °C in twoconditions: constant darkness and with a 5-min UV pulse. Differentialexpression analysis of the resulting transcriptomic data showed that2% of the genes changed their expression as a result of UV exposure,of which about 70% represented upregulated genes. Even though a 5 minUV pulse was not sufficient to trigger a massive de-regulation, ouranalysis support that UV participates in photostimulated processes.As expected, among upregulated genes, we found those belonging to themycosporine cluster. Surprisingly, we were also able to detect anUV-mediated induction of circadian genes. This finding triggers newquestions about the effect of UV in endogenous rhythms in fungi.p { margin-bottom: 0.25cm; direction: ltr; color: rgb(0, 0, 10); line-height: 120%; text-align: left; }p.western { font-family: "Calibri", serif; font-size: 11pt; }p.cjk { font-family: "Calibri"; font-size: 11pt; }p.ctl { font-family: "Calibri"; font-size: 11pt; }