title: Charge as a selection criterion for translocation through the nuclear pore complex.
abstract: Nuclear pore complexes (NPCs) are highly selective filters that control the exchange of material between nucleus and cytoplasm. The principles that govern selective filtering by NPCs are not fully understood. Previous studies find that cellular proteins capable of fast translocation through NPCs (transport receptors) are characterized by a high proportion of hydrophobic surface regions. Our analysis finds that transport receptors and their complexes are also highly negatively charged. Moreover, NPC components that constitute the permeability barrier are positively charged. We estimate that electrostatic interactions between a transport receptor and the NPC result in an energy gain of several k(B)T, which would enable significantly increased translocation rates of transport receptors relative to other cellular proteins. We suggest that negative charge is an essential criterion for selective passage through the NPC.
authors.affiliation: School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts, United States of America.
authors.forename: Lucy J
authors.initials: LJ
authors.lastname: Colwell
authors.forename: Michael P
authors.initials: MP
authors.lastname: Brenner
authors.forename: Katharina
authors.initials: K
authors.lastname: Ribbeck
mesh_terms: D000595:Amino Acid Sequence; D016000:Cluster Analysis; D005656:Fungal Proteins / Q000378:metabolism; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D008954:Models, Biological; D008969:Molecular Sequence Data; D022022:Nuclear Pore / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D028861:Nuclear Pore Complex Proteins / Q000378:metabolism; D011485:Protein Binding; D021381:Protein Transport / Q000502:physiology; D012441:Saccharomyces cerevisiae; D055672:Static Electricity; D013816:Thermodynamics
chemical_list: D005656:Fungal Proteins; D028861:Nuclear Pore Complex Proteins