Transcriptome analysis of mediator Med20 mutant and dcr1 mutant in S.pombe

At Schizosaccharomyces pombe centromeres, non-coding RNAs are transcribed by RNA polymerase II and processed by the RNAi machinery to direct heterochromatin formation. Mediator is a regulator of RNA polymerase II transcription and we here demonstrated that it also controls the levels of centromeric transcripts. Loss of the Mediator subunit Med20 increases transcription of non-coding RNAs and disrupts the centromeric heterochromatin structure. We have used tilling arrays to study the gene expression changes in Med20 deletionVs WT and Med20 dcr1 double mutant Vs Dcr1 mutant in exponentially growing fission yeast cells to detect how the Med20 gene affect centromeric expression. RNA samples were taken from exponentially growing fission yeast cells and reverse transcribed cDNA from the RNA are hybridized to affymetrix pombe tilling arrays: wild type,med20 mutant, Dcr1 mutants and med20,dcr1 double mutant.