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Updated: May 28, 2026

Image-Based Methods to Study Membrane Trafficking Events in Stomatal Lineage Cells
Published on: May 12, 2023
FG repeats facilitate integral protein trafficking to the inner nuclear membrane
Alastair Rw Kerr1, Eric C Schirmer
1Wellcome Trust Centre for Cell Biology; University of Edinburgh; Edinburgh, UK.
Abstract:
The mechanism for nucleo-cytoplasmic transport of integral membrane proteins is poorly understood compared to transport of soluble molecules. We recently demonstrated that at least four distinct mechanisms can contribute to transport of integral proteins through the peripheral channels of the nuclear pore complex. One of these requires having multiple phenylalanine-glycine (FG) pairings on the integral protein. It also requires the nuclear pore complex protein Nup35, which separately contains FG repeats. FG-repeats on nuclear pore complex proteins in the central channel have been proposed to interact with FGs on transport receptors to facilitate transport of soluble proteins. Here we show that FG repeats occur quite frequently in both transmembrane and soluble proteins identified in multiple separate proteomic analyses of nuclear envelopes. We postulate that the FG repeats enable these proteins to function as their own transport receptors.
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