Figure 12-16. A model for how GTP hydrolysis by Ran provides directionality for nuclear transport.

Figure 12-16A model for how GTP hydrolysis by Ran provides directionality for nuclear transport

Movement through the pore complex of loaded nuclear transport receptors may occur by guided diffusion along the FG-repeats displayed by nucleoporins. The differential localization of Ran-GTP in the nucleus and Ran-GDP in the cytosol provides directionality (red arrows) to both nuclear import (left) and nuclear export (right). The hydrolysis of GTP to produce Ran-GDP is mediated by Ran-GAP and Ran Binding Protein on the cytosolic side of the nuclear pore complex.

From: The Transport of Molecules between the Nucleus and the Cytosol

Cover of Molecular Biology of the Cell
Molecular Biology of the Cell. 4th edition.
Alberts B, Johnson A, Lewis J, et al.
New York: Garland Science; 2002.
Copyright © 2002, Bruce Alberts, Alexander Johnson, Julian Lewis, Martin Raff, Keith Roberts, and Peter Walter; Copyright © 1983, 1989, 1994, Bruce Alberts, Dennis Bray, Julian Lewis, Martin Raff, Keith Roberts, and James D. Watson .

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