Genome-wide maps of GFPyTBP (ChIP-seq) in yeast kap114-KO SC1005 strains

Multiple nuclear transport receptors, collectively termed karyopherins in yeast, deliver TATA-binding protein (TBP) to the nucleus, facilitating promoter recognition and transcriptional preinitiation complex formation. Among these karyopherins, Kap114p exhibits a sub-nanomolar affinity for yeast TBP (yTBP), four orders of magnitude greater than its counterparts. We hypothesize that the strong binding affinity of Kap114p toward yTBP going beyond what is required for nuclear import facilitates additional functions. Here we employ ChIP-seq assays to profile genome-wide maps of yTBP (through an GFP tag) in yeast kap114-knockout SC1005 strains rescued without or with kap114 wildtype or Δ(899–956) mutant. Our results showed that Kap114p serves as a yTBP suppressor in the transcriptional regulatory network. Importantly, the Kap114p-dependent sequestration prevents a collapse of yTBP dynamics, required for yeast respondding to environmental stresses (e.g. salt stress). Genome-wide binding/occupancy profiling of GFPyTBP by ChIP-seq in yeast kap114-KO SC1005 strains (rescued without or with Kap114 wildtype or Δ(899–956) mutant)