DamID of Ima1 and Man1 in Schizosaccharomyces pombe

The metazoan nuclear periphery is involved in transcriptional regulation and chromatin organisation. To test whether this is also the case in the fission yeast Schizosaccharomyces pombe, we performed DamID experiments with two inner nuclear membrane (INM) proteins, Ima1 and Man1. The resulting map showed that about a third of the genome is associated with the nuclear periphery. We find that both INM proteins preferentially associate with lowly expressed genes, and are depleted from highly expressed genes. Further, intergenic regions of divergent gene pairs are more frequently associated with the periphery than convergent pairs, indicating that transcription points away from the periphery rather than toward it We recorded methylation levels for both Ima1- and Man1-Dam fusion proteins and compared them to Dam-only control samples. Three biological replicates for each experiment were done, except for Ima1, where just 2 arrays could be used.