Macromolecular assemblies can be intrinsically refractive to classical structural analysis, due to their size, complexity, plasticity and dynamic nature. One such assembly is the nuclear pore complex (NPC). The NPC is formed from ∼450 copies of 30 different proteins, called nucleoporins, and is the sole mediator of exchange between the nucleus and the cytoplasm in eukaryotic cells. Despite sign...

So far, only a few of the interactions between the ≈ 30 nucleoporins comprising the modular structure of the nuclear pore complex have been defined at atomic resolution. Here we report the crystal structure, at 2.6 Å resolution, of a heterotrimeric complex, composed of fragments of three cytoplasmically oriented nucleoporins of yeast: Nup82, Nup116, and Nup159. Our data show that the Nup82 frag...

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...

A modified procedure for the isolation of a nuclear pore complex-lamina fraction from rat liver nuclei is described. Evidence is provided that the isolated lamina, a 150-A thick, proteinaceous structure, apposes the inner nuclear envelope membrane, connecting nuclear pore complexes and surrounding the entire nucleus.

The massive nuclear pore complex mediates nucleocytoplasmic traffic ranging from a single histone to a viral genome. To date, dissecting mechanism has been more an exercise in prediction than biochemical certainty. A recent study combines recombinant proteins with nuclei reconstituted in vitro to test predictions in a startlingly productive manner.

The nuclear pore complex (NPC) mediates all nucleocytoplasmic transport, yet its structure and biogenesis remain poorly understood. In this study, we have functionally characterized interaction partners of the yeast transmembrane nucleoporin Ndc1. Ndc1 forms a distinct complex with the transmembrane proteins Pom152 and Pom34 and two alternative complexes with the soluble nucleoporins Nup53 and ...

objective (s) porin is a mitochondrial outer membrane channel, which usually functions as the pathway for the movement of various substances in and out of the mitochondria and is considered to be a component of the permeability transition (pt) pore complex that plays a role in the pt. we addressed the hypothesis that porin interacts with other mitochondrial proteins after ischemic injury. mater...

Nuclear pore complexes (NPCs) are gateways for nucleocytoplasmic exchange. To analyze their structure in a close-to-life state, we studied transport-active, intact nuclei from Dictyostelium discoideum by means of cryoelectron tomography. Subvolumes of the tomograms containing individual NPCs were extracted in silico and subjected to three-dimensional classification and averaging, whereby distin...

Functional understanding of the nuclear envelope requires the identification of its component proteins and their interactions. Trypanosomes cause human and livestock diseases worldwide but are so divergent from animals and fungi that in silico searches for homologs of proteins are frequently of low value. Here we describe a strategy for the straightforward identification of nuclear envelope pro...

Nuclear pore complexes have been isolated in association with a 150 A thick lamina by detergent and salt fractionation of nuclear envelopes from rat liver. The pore complexes exhibit characteristic morphology and appear to be attached in a highly specific orientation to the lamina, which extends over relatively large areas. The pore complex-lamina fraction is composed of three major and several...