Select languageSelect language
Institut für Physiologie und Pathophysiologie

Single Molecules

Figure 1: Schematic experimental set-up: actin filaments move over a surface of myosin or heavy meromyosin
Figure 2: Movement of fluorescently labeled actin filaments recorded with a highly sensitive CCD camera

Molecular dynamics in the in vitro motility assay

The ability of heart and skeletal muscle to contract is based on the fundamental interaction of the two contractile proteins actin and myosin. This basic interaction can be studied in the in vitro motility assay originally devised by Kron and Spudich (1986), where fluorescently labeled actin filaments move over a surface of immobilised myosin or heavy meromyosin. The motion of actin filaments is recorded with a highly sensitive fluorescence imaging set-up.

 

Many parameters of this motion have been shown to be of significant importance for our understanding of the acto-myosin interaction, as e.g. the filament velocity is thought to be directly correlated to the unloaded shortening velocity of muscle fibers and therefore a direct reflection of the cross-bridge turnover rate. Also this assay is ideally suited to screen the functional domains of myosin, such as the nucleotide binding site, the actin binding site, the converter region and the lever arm. Furthermore myosin isoforms and actin mutants can be selectively studied in this assay.

 

more movies

 

 

Force measurements with optical tweezers

Optical tweezers is the name of a technique for holding small objects such as polystyrene beads in the focus of a laser beam. The diffraction of the laser at the bead surface produces a force that always directs the bead towards the laser focus. This effect is simply due to the geometry of the configuration and can be applied to measure very small forces, like the force between a single myosin and actin molecule.


24.10.2017       13:30   /   INF 327, Seminar Room 1

 

Hypoxia and uterine contractions: Something old and something new

Prof. Dr. Susan Wray

Dept. of Cellular and Molecular Physiology, University of Liverpool, United Kingdom

  

24.10.2017       18:00   /   INF 410 (Med. Clinic), Auditorium

 

Calcium in the heart: in and out of control

Prof. Dr. David Eisner

Manchester Institute for Collaborative Research on Ageing, University of Manchester, United Kingdom


(seminar of Heidelberg University Hospital and German Center for Cardiovascular Disease (DZHK); host: Prof. Dr. M. Hecker, Inst. of Physiology and Pathophysiology, Heidelberg University)

  

Neue Publikationen

*

AP-1 Oligodeoxynucleotides Reduce Aortic Elastolysis in a Murine Model of Marfan Syndrome. Mol Ther Nucleic Acids. 2017 Dec 15; 9: 69–79. Epub 2017 Sep 20. doi: 10.1016/j.omtn.2017.08.014

*

Allosteric inhibition of carnosinase (CN1) by inducing a conformational shift. J Enzyme Inhib Med Chem. 2017 Dec;32(1):1102-1110. doi: 10.1080/14756366.2017.1355793.

*

Transcription factor decoy technology: a therapeutic update. Biochem Pharmacol. 2017 Nov 15;144:29-34. doi: 10.1016/j.bcp.2017.06.122. Epub 2017 Jun 19. Review.

*

Subtype-specific differentiation of cardiac pacemaker cell clusters from human induced pluripotent stem cells. Stem Cell Res Ther. 2017 Oct 16;8(1):229. doi: 10.1186/s13287-017-0681-4.

*

Heteromeric channels formed by TRPC1, TRPC4 and TRPC5 define hippocampal synaptic transmission and working memory. EMBO J. 2017 Sep 15;36(18):2770-2789. doi: 10.15252/embj.201696369. Epub 2017 Aug 8

*

NO-sGC Pathway Modulates Ca2+ Release and Muscle Contraction in Zebrafish Skeletal Muscle. Front Physiol. 2017 Aug 23;8:607. doi: 10.3389/fphys.2017.00607. eCollection 2017.


Institut für
Physiologie und Pathophysiologie

Universität Heidelberg

Im Neuenheimer Feld 326

69120 Heidelberg

Telefon:+49 6221 54-4056
Telefax:+49 6221 54-6364
E-Mail:susanne.bechtel@
physiologie.uni-heidelberg.de