Regensburg 2022 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
BP: Fachverband Biologische Physik
BP 12: Poster 2
BP 12.11: Poster
Dienstag, 6. September 2022, 17:30–19:30, P4
Measuring the stiffness of neuronal growth cones with scanning ion conductance microscopy — •Aylin Balmes1, Hannes Schmidt2, and Tilman E. Schäffer1 — 1Institute of Applied Physics, University Tübingen, Germany — 2Interfaculty Institute of Biochemistry (IFIB), University Tübingen, Germany
It was recently demonstrated that nanoscale dynamic structural changes in live neurons can be visualized using scanning ion conductance microscopy (SICM). In SICM imaging the sample is scanned with an electrolyte-filled nanopipette to which a voltage and a pressure are applied and the ion current through the nanopipette is measured. The sample topography and stiffness (Young's modulus) can thereby be derived with high spatial and temporal resolution. There is no direct mechanical contact between the probe and the sample during SICM imaging, making it a very suitable technique to study fragile samples such as neurons. In this study we use SICM to investigate the stiffness of growth cones of dorsal root ganglion (DRG) neurons, which have previously been used to study axonal branching, an important process in neuronal development. Studies showed that a signaling cascade involving the second messenger cyclic guanosine monophosphate (cGMP) which is generated upon binding of C-type natriuretic peptide (CNP) to the receptor guanylyl cyclase B regulates the bifurcation of DRG axons. Our measurements show that the presence of cGMP and CNP reduces growth cone stiffness. This alteration in stiffness could be linked to changes in the actin cytoskeleton and might play a role in the regulation of axon bifurcation.