The permeability barrier of nuclear pore complexes appears to operate via hydrophobic exclusion
AUTOR(ES)
Ribbeck, Katharina
FONTE
Oxford University Press
RESUMO
Nuclear pore complexes (NPCs) restrict the nucleocytoplasmic flux of most macromolecules, but permit facilitated passage of nuclear transport receptors and their cargo complexes. We found that a simple hydrophobic interaction column can mimic the selectivity of NPCs surprisingly well and that nuclear transport receptors appear to be the most hydrophobic soluble proteins. This suggests that surface hydrophobicity represents a major sorting criterion of NPCs. The rate of NPC passage of cargo–receptor complexes is, however, not dominated just by properties of the receptors. We found that large cargo domains drastically hinder NPC passage and require more than one receptor molecule for rapid translocation. This argues against a rigid translocation channel and instead suggests that NPC passage involves a partitioning of the entire translocating species into a hydrophobic phase, whereby the receptor:cargo ratio determines the solubility in that permeability barrier. Finally, we show that interfering with hydrophobic interactions causes a reversible collapse of the permeability barrier of NPCs, which is consistent with the assumption that the barrier is formed by phenylalanine-rich nucleoporin repeats that attract each other through hydrophobic interactions.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=126029Documentos Relacionados
- Cargo surface hydrophobicity is sufficient to overcome the nuclear pore complex selectivity barrier
- Kinetic analysis of translocation through nuclear pore complexes
- Plant mitochondria actively import DNA via the permeability transition pore complex
- Localization of a myosin heavy chain-like polypeptide to Drosophila nuclear pore complexes.
- Imaging of single-molecule translocation through nuclear pore complexes