Parts | Days | Selection | Search | Downloads | Help
MO: Molekülphysik
MO 7: Poster I (Experimentelle Techniken, Spektroskopie, Cluster)
MO 7.8: Poster
Wednesday, March 6, 2002, 11:00–13:00, Schloss
Mobility and binding of U1 snRNPs within nuclear speckles observed by single particle fluorescence microscopy — •T. Kues1, A. Dickmanns2, R. Lührmann2, R. Peters1, and U. Kubitscheck3 — 1Westälische Wilhelms-Universität Münster, Institut für Medizinische Physik und Biophysik, Robert-Koch-Strasse 31, 48149 Münster — 2Max-Planck-Institut für Biophysikalische Chemie, Zelluläre Biochemie, 37077 Göttingen — 3Institut für Experimentelle Physik, Postfach 330440, 28334 Bremen
Isolated U1 snRNPs were fluorescently labeled and incubated with permeabilized 3T3 cells in the presence of importin b and an ATP regenerating system. By confocal microscopy U1 snRNPs were found to yield a speckled intranuclear distribution, which basically overlapped with the distribution of ASF/SF2. Employing a laser video-microscope single U1 snRNPs were tracked at a spatial precision of down to 35 nm and a time resolution of 30-150 ms. The analysis of the U1 snRNP trajectories revealed particle fractions with low and high mobility, and a virtually immobile one. The latter fraction represented bound U1 snRNPs. The mean square displacements of the mobile fractions were independent of time suggesting arrays of concentrated binding sites. The locations of bound U1 snRNPs with regard to ASF-GFP-labeled speckles were analyzed.