Biomedical subjects

C Gerner

Publications and source records attributed to C Gerner.

21 records · Page 2Linked to original sources

PubMed1997

Common nuclear matrix proteins in rat tissues.

Nuclear matrix proteins have been defined as insoluble residual proteins resulting from treatment of isolated nuclei with nucleases, detergents and high ionic strength buffers. They are considered as in part representing the proteins constituting the three-dimensional framework of the interphase nucleus. Though cell-specific nuclear matrix proteins have been differentiated from ubiquitously occurring (common) nuclear matrix proteins, the number and types of common nuclear matrix proteins have not yet been unequivocally established. In the present study nuclear matrix proteins were prepared from isolated nuclei of rat kidney, liver, lung, spleen and testes. The matrix proteins were separated by two-dimensional (2-D) electrophoresis and silver stained. Then the spot patterns were compared by computer-assisted image analysis. Composite images were derived for nuclear matrix proteins of individual tissues. Finding between 396-483 spots per tissue, a total of 964 individual spots were registered. Of these, 102 were common nuclear matrix proteins, as appearing in each of the tissue-characteristic images. The apparent molecular mass and pI data may serve for further identification of these nuclear proteins.

Animals↗

PubMed1997

Two-dimensional electrophoresis reveals a nuclear matrix-associated nucleolin complex of basic isoelectric point.

A monoclonal antibody was raised against a salt-extractable fraction of nuclear matrix / intermediate filament scaffolds of polarized MDCK cells. The antibody recognized an approximately 100 kDa protein in total cell lysates and nuclear matrices of various human cells and tissues and stained nucleolar structures in immunofluorescence microscopy. By partial sequencing of five peptides derived from immunoprecipitated protein, the targeted antigen was found to be homologous to human nucleolin. After two-dimensional electrophoresis of total HeLa cell lysates, immunoreactive bands were detected at isoelectric point (pI) 5.5--6.1, characteristic for nucleolin, and at pI 8.5--9. Whereas the protein focusing at acidic pI was found in Triton X-100-soluble cellular fractions, the antigen focusing at basic pI was exclusively contained in the residual nuclear fraction and was solubilized upon treatment of nuclear matrices with RNAse. The component solubilized by RNAse treatment was still detected at basic pI in two-dimensional electrophoresis. However, upon immunoprecipitation of the antigen from the RNAse-released fraction in the presence of sodium dodecyl sulfate (SDS), the nuclear matrix-derived antigen was positioned at pI 5--6. The present data indicate that the nuclear matrix-bound nucleolin is associated with ribonucleoproteins and a basic component resisting dissociation under conditions of isoelectric focusing.

Animals↗

PubMed1995

Instrumental outcome devaluation is attenuated by the anti-emetic ondansetron.

In three experiments we assessed the effect of an anti-emetic, the selective 5-HT antagonist ondansetron, on (1) the conditioning of a taste aversion using lithium chloride (LiCl); (2) the expression of that aversion; and (3) instrumental outcome-devaluation effects. In Experiment 1 it was found that ondansetron reduced the aversion induced by LiCl when administered prior to the LiCl injection and also attenuated the expression of that aversion when administered prior to test sessions. In Experiments 2 and 3, thirsty rats were trained, in a single session, to lever press and chain pull for sucrose and saline solutions concurrently before being injected with LiCl. They were then re-exposed to both solutions, one after injection of vehicle and the other after injection of ondansetron. In a choice extinction test on the levers and chains, animals performed more of the action whose training outcome was re-exposed under ondansetron than the other action, whether the test was conducted after an injection of vehicle or after one of ondansetron.

Animals↗