Summary
A Nature study combining measurements in living cells with molecular-dynamics simulations found that flexible proteins forming the nuclear pore’s selective barrier are highly mobile. The researchers report that glycosylation and importin-β help maintain this dynamic state.
Flexible proteins that form the selective barrier inside nuclear pores are highly mobile in living cells, according to a Nature study combining cellular measurements with molecular-dynamics simulations. The researchers also report that glycosylation—a sugar modification to proteins—and the transport protein importin-β help preserve this dynamic state.
A changing barrier at the cell’s nuclear gateway
Nuclear pores are channels in the membrane surrounding a cell’s nucleus. They regulate the movement of molecules between the nucleus, where the cell’s DNA is housed, and the surrounding cytoplasm. Some molecules pass through readily, while others need transport proteins to guide them.
The pore’s selective barrier includes flexible proteins with repeated phenylalanine-glycine, or FG, sequences. Rather than forming a rigid wall, these chains can move and rearrange. The Nature report describes them as highly mobile in living cells, supporting a picture of the barrier as a dynamic structure.
The study, by Yu and colleagues, paired measurements in living cells with molecular-dynamics simulations, which model how molecules move and interact. The briefing reports that both approaches were used to investigate the FG barrier. It says that glycosylation and importin-β help maintain the proteins’ mobile state.
Why mobility matters for transport
A nuclear pore must be selective while still allowing the cell to move a wide range of molecules across the nuclear envelope. Flexible barrier proteins offer a way to understand how the pore can change its arrangement as transport occurs, rather than behaving as a fixed sieve. Importin-β is a carrier involved in moving cargo through nuclear pores, so its reported role in preserving barrier dynamics links transport to the physical state of the barrier itself.
“Liquid-like” describes the mobility of the protein chains; it does not mean that the pore is a pool of ordinary liquid. The finding instead points to a barrier whose components remain flexible, with protein modification and transport machinery helping sustain that flexibility.
The work is reported in Yu et al., “Glycosylation and importins liquefy the FG barrier in live nuclear pores,” published in Nature in 2026.