Laser-Konfokalmikroskop mit Spinning-Disk Einheit
Zusammenfassung der Projektergebnisse
The Spinning Disk Confocal microscope was used by several laboratories and projects in the frame of the Life Imaging Core Facility LIC of the University of Freiburg. Project Prof. W. Driever: Initiation of motile cell behavior in embryonic development occurs during late blastula stages, when the strong adhesion of blastomeres has to be modulated to enable dynamic behavior. We showed that, in zebrafish embryos maternal and zygotic mutant for the stem cell transcription factor Pou5f1/Oct4, which are delayed in the epiboly gastrulation movement, all blastomeres are defective in E-cadherin (E-cad) endosomal trafficking, and E-cad accumulates at the plasma membrane. We found that Pou5f1-dependent control of EGF expression regulates endosomal E-cad trafficking. EGF receptor may act via modulation of p120 activity. Loss of E-cad dynamics reduces cohesion of cells in reaggregation assays. Quantitative analysis of cell behavior indicates that dynamic E-cad endosomal trafficking is required for epiboly cell movements. We hypothesize that dynamic control of E-cad trafficking is essential to effectively generate new adhesion sites when cells move relative to each other. Project Jun. Prof V. Lecaudey: Cellular mechanisms of lateral line primordium morphogenesis in zebrafish. The microscope was used to investigate (1) the role of the actin binding protein Shroom3 during lateral line morphogenesis; (2) the role of the junction-localized scaffolding protein Amotl2a and (3) of the microtubule binding protein Stathmin1a during lateral line morphogenesis and migration. Project Prof. M. Simons: Research project investigating control of cell polarization, directional migration and wound healing by high-precision pH manipulation to identify molecular requirements for spontaneous and directional polarization of human keratinocytes. Project Prof. T. Laux: The microscope was used to investigate stem cell regulation in plant meristems. In this project, when investigating stem cell regulation in the Arabidopsis shoot meristem, the microscope was used to detect expression of the stem cell antagonist, LCR. In the project WOX genes regulating apical embryo patterning the expression of several reporter genes in the Arabidopsis zygote was explored. Because the zygote is tightly embedded in maternal tissue, detection of fluorescent reporter signaling has to occur through several tissue layers. Project Prof. R. Murphy: Dynamics of Cell Morphology and Organization during Neuronal Differentiation. Images were used to create a generative model of the changes that occur and the variation within cell populations during specific cell behaviors. Prof. G. Walz: Die molekularen Funktionen von Nephrocystin-4: In dem Projekt wird die Lokalization von Nephrocystin-4 (NPHP4) in Relation zum Basalkörper von Zilien untersucht. Als Modellsystem dient das Xenopus Epidermis-System, welche isolierte, multiziliäre Zellen mit motilen Zilien enthält. Mittels der hochauflösende Eigenschaften des ZEISS SDCM konnten Strukturen am Basalkörper identifiziert, die bisher noch nicht charakterisiert wurden. Außerdem konnte die Lokalisation von NPHP4 in Relation zu anderen Proteinen am Basalkörper präzise untersucht werden.
Projektbezogene Publikationen (Auswahl)
- Transcriptional activation of Arabidopsis axis patterning genes WOX8/9 links zygote polarity to embryo development. Developmental Cell (2011) 20, 264-270
Ueda, M., Zhang, Z., and Laux, T.
- Shroom3 is required downstream of FGF signalling to mediate proneuromast assembly in zebrafish. Development (2012) 139, 4571-4581
Ernst, S., Liu, K., Agarwala, S., Moratscheck, N., Avci, M. E., Nogare, D. D., Chitnis, A. B., Ronneberger, O. and Lecaudey, V.
- A Protodermal miR394 Signal Defines a Region of Stem Cell Competence in the Arabidopsis Shoot Meristem. Developmental Cell (2013) 24,125-132
Knauer, S., Holt, A. L., Rubio-Somoza, I., Tucker, E. J., Hinze, A., Pisch, M., Javelle, M., Timmermans, M. C., Tucker, M. R. and Laux, T.
- Nondirectional radial intercalation dominates deep cell behavior during zebrafish epiboly. Biology Open (2013) 2, 845-854
Bensch, R., Song, S., Ronneberger, O., and Driever, W.
- Pou5f1-Dependent EGF Expression Controls E-Cadherin Endocytosis, Cell Adhesion, and Zebrafish Epiboly Movements. Developmental Cell (2013) 24, 486-501
Song, S., Eckerle, S., Onichtchouk, D., Marrs, J.A., Nitschke, R., and Driever, W
