8H5B

The cryo-EM structure of nuclear transport receptor Kap114p complex with yeast TATA-box binding protein

Summary for 8H5B

• Entry DOI: 10.2210/pdb8h5b/pdb
• EMDB information: 34490
• Descriptor: Importin subunit beta-5, TATA-box-binding protein (2 entities in total)
• Functional Keywords: nuclear transport receptor kap114p, yeast tata-box binding protein, protein transport
• Biological source: Saccharomyces cerevisiae S288C; More
• Total number of polymer chains: 2
• Total formula weight: 134140.45

Authors

Hsia, K.C.,Liao, C.C.,Wang, C.H.,Wu, Y.M. (deposition date: 2022-10-12, release date: 2023-09-20)

Primary citation

Liao, C.C.,Wang, Y.S.,Pi, W.C.,Wang, C.H.,Wu, Y.M.,Chen, W.Y.,Hsia, K.C.
Structural convergence endows nuclear transport receptor Kap114p with a transcriptional repressor function toward TATA-binding protein.
Nat Commun, 14:5518-5518, 2023

PubMed Abstract: The transcription factor TATA-box binding protein (TBP) modulates gene expression in nuclei. This process requires the involvement of nuclear transport receptors, collectively termed karyopherin-β (Kap-β) in yeast, and various regulatory factors. In previous studies we showed that Kap114p, a Kap-β that mediates nuclear import of yeast TBP (yTBP), modulates yTBP-dependent transcription. However, how Kap114p associates with yTBP to exert its multifaceted functions has remained elusive. Here, we employ single-particle cryo-electron microscopy to determine the structure of Kap114p in complex with the core domain of yTBP (yTBP). Remarkably, Kap114p wraps around the yTBP N-terminal lobe, revealing a structure resembling transcriptional regulators in complex with TBP, suggesting convergent evolution of the two protein groups for a common function. We further demonstrate that Kap114p sequesters yTBP away from promoters, preventing a collapse of yTBP dynamics required for yeast responses to environmental stress. Hence, we demonstrate that nuclear transport receptors represent critical elements of the transcriptional regulatory network.

PubMed: 37684250
DOI: 10.1038/s41467-023-41206-9

Experimental method

ELECTRON MICROSCOPY (4.03 Å)