Effect of Leptomycin B on Gcn4 and Crm1-T539C binding patterns in budding yeast

Leptomycin B (LMB) reacts covalently to C539 located in the nuclear export sequence (NES) binding pocket in yeast strains with the crm1-T539C mutation, consequently inhibiting nuclear export of proteins. When Crm1 is inhibited by LMB, hundreds of genes experience a strong decrease in nascent transcription and both chromatin association with the nuclear pore as well as peripheral localization of various genes, such as those bound by transcription factor Gcn4, are lost. To better understand the influence of LMB in vivo, we performed ChEC-seq2 with crm1-T539C and Gcn4 in LMB-sensitive yeast strains. Yeast cells were grown in synthetic complete medium containing glucose (SDC) at 30C. Crm1 was inhibited by treating cultures with 185 nM leptomycin B (LMB) in ethanol or ethanol only for 30 min at 30C. All experiments have at least three biological replicates.