Translocation through the nuclear pore: Kaps pave the way.

Area of Science:

• Cell Biology
• Biophysics

Background:

• Nuclear pore complexes (NPCs) regulate transport between the nucleus and cytoplasm.
• Phenylalanine-glycine (FG) domains within NPCs are crucial for this transport, acting as binding sites.
• The precise conformation and function of FG domains in vivo remain debated.

Purpose of the Study:

• To analyze current data on NPC transport mechanisms.
• To evaluate existing models of FG domain function within NPCs.
• To determine the most accurate model for nucleocytoplasmic transport.

Main Methods:

• Review of recent experimental data from optical single transporter recording and superresolution microscopy.
• Analysis of studies using artificial nanopores.
• Comparative evaluation of transport models including Brownian affinity gating, selective phase gating, reversible FG domain collapse, and Reduction of Dimensionality (ROD).

Main Results:

• New experimental data provides insights into FG domain behavior in vivo.
• A simplified version of the Reduction of Dimensionality (ROD) model effectively explains the observed transport phenomena.
• Existing models like Brownian affinity gating and selective phase gating are less supported by current data.

Conclusions:

• The Reduction of Dimensionality (ROD) model, in a simplified form, offers a robust explanation for nucleocytoplasmic transport.
• Understanding FG domain arrangement and dynamics is key to deciphering NPC function.
• This work has broad implications for the study of nucleocytoplasmic transport in eukaryotes.