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In this first application of optical single transporter recording (OSTR), a recently established technique for optically monitoring the activity of single transporters in membrane patches (Tschödrich-Rotter and Peters. 1998. J. Microsc. 192:114-125), the passive permeability of the nuclear pore complex (NPC) was measured for a homologous series of hydrophilic probe molecules. Nuclei were isolated from Xenopus oocytes and firmly attached to filters containing small cylindrical pores. Transport through membrane patches spanning filter pores was measured by scanning microphotolysis. Thus the permeability coefficients of single NPCs were determined for fluorescently labeled dextrans of approximately 4, 10, and 20 kDa. Dextrans of >/=40 kDa could not permeate the NPC. The data were consistent with a model in which the NPC contains a single diffusion channel. By application of established theories for the restricted diffusion through small pores, the diffusion channel was approximated as a cylinder with a radius of 4.4-6.1 nm (mean 5. 35 nm). Because the transport rate constant of the single NPC was known, the equivalent length of the channel could be also determined and was found to be 40-50 nm (mean 44.5 nm). The symmetry of the NPC implies that a singular component such as the diffusion channel is located at the center of the NPC. Therefore a common transport pathway apparently mediates both passive and signal-dependent transport. To test this hypothesis, measurements of signal-dependent transport and of the mutual effects signal-dependent and passive transport may exert on each other are in progress.
Akey,
Architecture of the Xenopus nuclear pore complex revealed by three-dimensional cryo-electron microscopy.
1993, Pubmed,
Xenbase
Akey,
Architecture of the Xenopus nuclear pore complex revealed by three-dimensional cryo-electron microscopy.
1993,
Pubmed
,
Xenbase
Akey,
Structural plasticity of the nuclear pore complex.
1995,
Pubmed
,
Xenbase
Bean,
The physics of porous membranes--neutral pores.
1972,
Pubmed
Borer,
Major nucleolar proteins shuttle between nucleus and cytoplasm.
1989,
Pubmed
,
Xenbase
Cole,
Nucleocytoplasmic transport: driving and directing transport.
1998,
Pubmed
Dingwall,
A polypeptide domain that specifies migration of nucleoplasmin into the nucleus.
1982,
Pubmed
,
Xenbase
Evans,
Biochemical fractionation of oocytes.
1991,
Pubmed
,
Xenbase
Feldherr,
The location of the transport gate in the nuclear pore complex.
1997,
Pubmed
,
Xenbase
Fischer,
The HIV-1 Rev activation domain is a nuclear export signal that accesses an export pathway used by specific cellular RNAs.
1995,
Pubmed
GOLDSTEIN,
Localization of nucleusspecific protein as shown by transplantation experiments in Amoeba proteus.
1958,
Pubmed
Görlich,
Transport into and out of the cell nucleus.
1998,
Pubmed
Hinshaw,
Architecture and design of the nuclear pore complex.
1992,
Pubmed
,
Xenbase
Kalderon,
Sequence requirements for nuclear location of simian virus 40 large-T antigen.
,
Pubmed
Lang,
Molecular mobility and nucleocytoplasmic flux in hepatoma cells.
1986,
Pubmed
Mattaj,
Nucleocytoplasmic transport: the soluble phase.
1998,
Pubmed
Maul,
The nuclear and the cytoplasmic pore complex: structure, dynamics, distribution, and evolution.
1977,
Pubmed
Meier,
Nopp140 shuttles on tracks between nucleolus and cytoplasm.
1992,
Pubmed
Melchior,
Mechanisms of nuclear protein import.
1995,
Pubmed
Michael,
A nuclear export signal in hnRNP A1: a signal-mediated, temperature-dependent nuclear protein export pathway.
1995,
Pubmed
Moore,
The two steps of nuclear import, targeting to the nuclear envelope and translocation through the nuclear pore, require different cytosolic factors.
1992,
Pubmed
,
Xenbase
Nigg,
Nucleocytoplasmic transport: signals, mechanisms and regulation.
1997,
Pubmed
Paine,
Nuclear envelope permeability.
1975,
Pubmed
Paine,
Drag coefficients for the movement of rigid spheres through liquid-filled cylindrical pores.
1975,
Pubmed
Paine,
Nucleocytoplasmic movement of fluorescent tracers microinjected into living salivary gland cells.
1975,
Pubmed
Panté,
Toward the molecular dissection of protein import into nuclei.
1996,
Pubmed
PAPPENHEIMER,
Filtration, diffusion and molecular sieving through peripheral capillary membranes; a contribution to the pore theory of capillary permeability.
1951,
Pubmed
Pemberton,
Transport routes through the nuclear pore complex.
1998,
Pubmed
Peters,
Fluorescence microphotolysis to measure nucleocytoplasmic transport and intracellular mobility.
1986,
Pubmed
Peters,
Nucleo-cytoplasmic flux and intracellular mobility in single hepatocytes measured by fluorescence microphotolysis.
1984,
Pubmed
Peters,
Nuclear envelope permeability measured by fluorescence microphotolysis of single liver cell nuclei.
1983,
Pubmed
Peters,
Transients of perforin pore formation observed by fluorescence microscopic single channel recording.
1990,
Pubmed
Peters,
A microfluorimetric study of translational diffusion in erythrocyte membranes.
1974,
Pubmed
Reichelt,
Correlation between structure and mass distribution of the nuclear pore complex and of distinct pore complex components.
1990,
Pubmed
,
Xenbase
Reynolds,
Permeability properties of mammalian cell nuclei in living cells and in vitro.
1984,
Pubmed
Smith,
Oogenesis and oocyte isolation.
1991,
Pubmed
,
Xenbase
Stevens,
RNA transport from nucleus to cytoplasm in Chironomus salivary glands.
1966,
Pubmed
Tschödrich-Rotter,
An optical method for recording the activity of single transporters in membrane patches.
1998,
Pubmed
Tschödrich-Rotter,
Optical single-channel analysis of the aerolysin pore in erythrocyte membranes.
1996,
Pubmed
Wedekind,
Scanning microphotolysis: a new photobleaching technique based on fast intensity modulation of a scanned laser beam and confocal imaging.
1994,
Pubmed
Wedekind,
Line-scanning microphotolysis for diffraction-limited measurements of lateral diffusion.
1996,
Pubmed
Wen,
Identification of a signal for rapid export of proteins from the nucleus.
1995,
Pubmed
