The FG-repeat domain of the yeast Rip1 protein (Rip1p) was identified initially as a possible target for the nuclear export signal (NES) of the HIV-1 Rev protein in a yeast two-hybrid assay. Rip1p is inessential, associated with nuclear pore complexes, and structurally related to the FG-nucleoporin family of pore proteins. It contributes to HIV-1 Rev-mediated RNA export and is also important fo...

In this article, we are interested in the existence of positive solutions for the following Kirchhoff type system  −M1 (∫ Ω |x| −ap|∇u|p dx ) div(|x|−ap|∇u|p−2∇u) = λ|x|−(a+1)p+c1 (f(v)− 1 uα ) in Ω, −M2 (∫ Ω |x| −bq |∇v|q dx ) div(|x|−bq |∇v|q−2∇v) = λ|x|−(b+1)q+c2 (g(u)− 1 vβ ) in Ω, u = v = 0 on ∂Ω, (1) where Ω is a bounded smooth domain of R with 0 ∈ Ω, 1 < p, q < N , 0 ≤ a, b < N−p p , c...

Soluble karyopherins of the importin-β (impβ) family use RanGTP to transport cargos directionally through the nuclear pore complex (NPC). Whether impβ or RanGTP regulate the permeability of the NPC itself has been unknown. In this study, we identify a stable pool of impβ at the NPC. A subpopulation of this pool is rapidly turned-over by RanGTP, likely at Nup153. Impβ, but not transportin-1 (TRN...

Nucleocytoplasmic transport is mediated by nuclear pore complexes (NPCs), enormous assemblies composed of multiple copies of ~30 different proteins called nucleoporins. To unravel the basic scaffold underlying the NPC, we have characterized the species-specific scaffold nucleoporin Nup37 and ELY5/ELYS. Both proteins integrate directly via Nup120/160 into the universally conserved heptameric Y-c...

All nucleocytoplasmic traffic of macromolecules occurs through nuclear pore complexes (NPCs), which function as stents in the nuclear envelope to keep nuclear pores open but gated. Three studies in this issue (Flemming, D., P. Sarges, P. Stelter, A. Hellwig, B. Böttcher, and E. Hurt. 2009. J. Cell Biol. 185:387-395; Makio, T., L.H. Stanton, C.-C. Lin, D.S. Goldfarb, K. Weis, and R.W. Wozniak. 2...

To fulfil their function, nuclear pore complexes (NPCs) must discriminate between inert proteins and nuclear transport receptors (NTRs), admitting only the latter. This specific permeation is thought to depend on interactions between hydrophobic patches on NTRs and phenylalanine-glycine (FG) or related repeats that line the NPC. Here, we tested this premise directly by conjugating different hyd...

Nucleocytoplasmic transport is mediated by the interaction of transport factors (TFs) with disordered phenylalanine-glycine (FG) repeats that fill the central channel of the nuclear pore complex (NPC). However, the mechanism by which TFs rapidly diffuse through multiple FG repeats without compromising NPC selectivity is not yet fully understood. In this study, we build on our recent NMR investi...

Nuclear pore complexes (NPCs) form aqueous conduits in the nuclear envelope and gate the diffusion of large proteins between the cytoplasm and nucleoplasm. NPC proteins (nucleoporins) that contain phenylalanine-glycine motifs in filamentous, natively unfolded domains (FG domains) line the diffusion conduit of the NPC, but their role in the size-selective barrier is unclear. We show that deletio...

The purpose of this study was to begin to describe the neural circuit within the abdominal ganglion that modulates renal functioning in Aplysia. We found that the previously described cholinergic neuron L10 and peptidergic left upper quadrant (LUQ) neurons have important roles in the control of the kidney. Cell L10 and a subset of the LUQ cells branch extensively within the kidney and send majo...

In this work, SiO2 –ZrO2 mixed oxides was prepared by the polymeric sol–gel route. The characterization of pore structure, which determines the permeation process of membrane, is of great importance. So far, most investigations have focused on such pore structure as specific surface area and pore size distribution, but the surface fractal, the important parameter reflecting the roughness of por...