QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

First published online June 23, 2005
doi: 10.1242/10.1242/jcs.02429

This Article Summary Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Shahin, V. Articles by Oberleithner, H. Search for Related Content PubMed PubMed Citation Articles by Shahin, V. Articles by Oberleithner, H. Social Bookmarking                         What's this?

Glucocorticoids remodel nuclear envelope structure and permeability

Victor Shahin^*,, Yvonne Ludwig^*, Claudia Schafer, Dessy Nikova and Hans Oberleithner

Institute of Physiology II, University of Münster, Robert-Koch Str. 27b, 48149 Münster, Germany

View larger version (15K): [in a new window]   Fig. 1. Idealized force-distance curve describing a single approach-retract cycle of the AFM tip, which is continuously repeated during surface scanning. The AFM tip is approaching the sample surface (A). The initial contact between the tip and the surface is mediated by the attractive van der Waals forces (contact) that lead to an attraction of the tip toward the surface (B). Hence, the tip applies a constant and default force upon the surface that leads to sample indentation and cantilever deflection (C). Subsequently, the tip tries to retract and to break loose from the surface (D). Various adhesive forces between the sample and the AFM tip, however, hamper tip retraction. These adhesive forces can be taken directly from the force-distance curve (E). The tip withdraws and looses contact to the surface upon overcoming of the adhesive forces (F).

View larger version (11K): [in a new window]   Fig. 2. Effect of solvent (ethanol in water) and triamcinolone acetonide (TA) on nuclear envelope electrical conductivity upon 5 minutes of injection into glucocorticoid receptor-expressing X. laevis oocytes. Asterisk (*) indicates a statistically significant difference (unpaired t-test, P<0.001) between the mean data of solvent and TA experiments. The broken line indicates the mean NEEC value of eight non-injected GR-expressing oocytes. The latter mean value was set to 100% (control).

View larger version (23K): [in a new window]   Fig. 3. (A) Representative confocal fluorescence images of nuclear envelope permeability for 20 kDa FITC-dextran, nuclear fluorescence respectively, in response to triamcinolone acetonide (TA) and solvent at a time scale of 5 minutes after injection into glucocorticoid receptors-expressing X. laevis oocytes. (B) Change of nuclear envelope permeability for 20 kDa FITC-dextran, nuclear fluorescence respectively, in response to triamcinolone acetonide (TA) and solvent at a time scale of 5 and 60 minutes after injection of TA into glucocorticoid receptor-expressing X. laevis oocytes. Asterisk (*) indicates a statistically significant difference (unpaired t-test, P<0.0009) between the mean data of solvent and TA experiments.

View larger version (117K): [in a new window]   Fig. 4. AFM images of the cytoplasmic nuclear envelope surface of glucocorticoid receptor (GR)-expressing X. laevis oocytes 5 minutes after solvent (ethanol in water, at the left) or triamcinolone acetonide (at the right) injection.

View larger version (65K): [in a new window]   Fig. 5. Assessement of the hydrophobicity degree of NPC opening and NPC-free NE surface 5 minutes upon injection of either solvent or TA into X. laevis oocytes. The assessment of hydrophobicity was determined by measurement of the adhesion forces between the AFM tip and the scanned NE area, using a hydrophobic, aluminium coated AFM tip, CSC21 (Ultra-sharp, Mikro Masch, Anfatec, Germany). To obtain an array of force-distance curves, a hydrophobicity map, over the entire NE area being scanned, the so-called force-volume mode is applied. The white spikes in the upper force volume image result from loss of contact between the AFM tip and the sample. Nuclear envelope (NE), nuclear pore complexes (NPCs), triamcinolone acetonide (TA).

CiteULike

Complore

Connotea

Del.icio.us

Digg

Reddit

Technorati

Twitter