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Updated: Jun 22, 2026

Crystallization of Membrane Proteins in Lipidic Mesophases
Published on: March 28, 2011
Crystallization of the flexible nuclear import receptor importin-beta in the unliganded state
Noelia Roman1, Brenda Kirkby, Mary Marfori
1School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, NSW 2650, Australia.
Abstract:
The transport of macromolecules across the nuclear envelope is an essential eukaryotic process that enables proteins such as transcription factors, polymerases and histones to gain access to the genetic material contained within the nucleus. Importin-beta plays a central role in the nucleocytoplasmic transport process, mediating nuclear import through a range of interactions with cytoplasmic, nuclear and nuclear pore proteins such as importin-alpha, Ran, nucleoporins and various cargo molecules. The unliganded form of the full-length yeast importin-beta has been expressed and crystallized. The crystals were obtained by vapour diffusion at pH 6.5 and 290 K. The crystals belonged to space group P2(1) (unit-cell parameters a = 58.17, b = 127.25, c = 68.52 A, beta = 102.23). One molecule is expected in the asymmetric unit. The crystals diffracted to 2.4 A resolution using a laboratory X-ray source and were suitable for crystal structure determination.
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