Karuna Ganesh1, Febe van Maldegem1, Stephanie B. Telerman1, Paul Simpson1, Christopher M. Johnson1, Roger L. Williams1, Michael S. Neuberger1, Cristina Rada1
1Medical Research Council Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK
Tóm tắt
CTNNBL1 is a spliceosome‐associated protein that binds nuclear localization signals (NLSs) in splice factors CDC5L and Prp31 as well as the antibody diversifying enzyme AID. Here, crystal structures of human CTNNBL1 reveal a distinct structure from its closest homologue karyopherin‐α. CTNNBL1 comprises a HEAT‐like domain (including a nuclear export signal), a central armadillo domain, and a coiled‐coil C‐terminal domain. Structure‐guided mutations of the region homologous to the karyopherin‐α NLS‐binding site fail to disrupt CTNNBL1–NLS interactions. Our results identify CTNNBL1 as a unique selective NLS‐binding protein with striking differences from karyopherin‐αs.
