1M5N

Crystal structure of HEAT repeats (1-11) of importin b bound to the non-classical NLS(67-94) of PTHrP

Summary for 1M5N

• Entry DOI: 10.2210/pdb1m5n/pdb
• Related: 1QGK 1QGR
• Descriptor: Importin beta-1 subunit, Parathyroid hormone-related protein (3 entities in total)
• Functional Keywords: all helical protein, heat repeats, protein transport
• Biological source: Homo sapiens (human); More
• Cellular location: Cytoplasm: Q14974 P12272
• Total number of polymer chains: 2
• Total formula weight: 57170.10

Authors

Cingolani, G.,Bednenko, J.,Gillespie, M.T.,Gerace, L. (deposition date: 2002-07-09, release date: 2003-01-21, Last modification date: 2024-02-14)

Primary citation

Cingolani, G.,Bednenko, J.,Gillespie, M.T.,Gerace, L.
Molecular basis for the recognition of a nonclassical nuclear localization signal by importin beta
Mol.Cell, 10:1345-1353, 2002

PubMed Abstract: Nuclear import of proteins containing a classical nuclear localization signal (NLS) involves NLS recognition by importin alpha, which associates with importin beta via the IBB domain. Other proteins, including parathyroid hormone-related protein (PTHrP), are imported into the nucleus by direct interaction with importin beta. We solved the crystal structure of a fragment of importin beta-1 (1-485) bound to the nonclassical NLS of PTHrP. The structure reveals a second extended cargo binding site on importin beta distinct from the IBB domain binding site. Using a permeabilized cell import assay we demonstrate that importin beta (1-485) can import PTHrP-coupled cargo in a Ran-dependent manner. We propose that this region contains a prototypical nuclear import receptor domain, which could have evolved into the modern importin beta superfamily.

PubMed: 12504010
DOI: 10.1016/S1097-2765(02)00727-X

Experimental method

X-RAY DIFFRACTION (2.9 Å)