Transcription of lncRNA prt, clustered prt RNA sites for Mmi1 binding, and RNA polymerase II CTD phospho-sites govern the repression of pho1 gene expression under phosphate-replete conditions in fission yeast

DSR RNA binding by the Mmi1 YTH domain. EMSA was performed as described in Materials and Methods. (A) The RNA binding reaction mixtures contained 100 nM 5′ ³²P-labeled 14-mer or 24-mer RNAs (shown at bottom, with one or two DSR hexamers, highlighted in gray), and increasing concentrations of Mmi1(301–488) protein (125, 250, 500, or 1000 nM, proceeding from left to right in each titration series). (B) RNA binding reaction mixtures contained 100 nM 5′ ³²P-labeled 14-mer DSR RNA and 125, 250, 500, or 1000 nM Mmi1(311–488) or Mmi1(319–488). Mmi1-YTH was omitted from the control reactions in lanes indicated by (–). The free RNAs and RNA•protein complexes were resolved by native PAGE and visualized by autoradiography of the dried gels.