The Walentek lab wants to understand how self-organization is achieved in biological systems. We study mucociliary epithelia, found in various organs of most animals. They contain multiciliated cells, that produce fluid flow through beating of hair-like organelles on their surface, called cilia. Additionally, they are comprised of secretory and basal stem cells. We study mucociliary organization, gene regulation and signaling networks, which are remarkably similar across species and organs. Using a wide range of experimental and analytical techniques as well as multiple species and tissues for comparative studies, we reveal common principles, differences, and study evolutionary innovations at the molecular level. Our multi-disciplinary research benefits from close collaborations with clinicians and scientists from different disciplines in Freiburg and around the world. The human airways are also lined by a mucociliary epithelium, which removes inhaled pathogens to ensure respiratory health. Dysfunction of cilia or changes in the behavior of secretory cells and stem cells leads to diseases like ciliopathies, chronic obstructive pulmonary disease (COPD), fibrosis and lung cancer. By studying the principles of mucociliary development and regeneration, we therefore also contribute to the fundamental understanding of these diseases, that promotes diagnosis and the establishment of novel treatments, including personalized medicine approaches.

Keywords:

Developmental biology, self-organization, signaling integration, gene regulation, epigenetics, post-transcriptional RNA regulation, cilia, stem cells, Xenopus, chronic airway diseases.

10 selected publications:

• Temporal Notch signaling regulates mucociliary cell fates through Hes-mediated competitive de-repression.
  Brislinger-Engelhardt MM., Lorenz F., Haas M., Bowden S., Tasca A., Kreutz C., Walentek P. (2023) in revision
  BioRxiv: doi.org/10.1101/2023.02.15.528675
• A simple method to generate human airway organoids with externally-oriented apical membranes.
  Boecking CA.*, Walentek P.*, Zlock LT., Sun DI., Wolters PJ., Ishikawa H., Jin B-J., Haggie PM., Marshall WF., Verkman AS., Finkbeiner W. (2022) (*co-first)
  AJP Lung. Mar 1;322(3):L420-L437.
• Microridge-like structures anchor motile cilia.
  Yasunaga T., Wiegel J., Bergen MD., Helmstädter M., Epting D., Paolini A., Cicek Ö., Radziwill G., Engel C., Bronx T., Ronneberger O., Walentek P., Ulbrich MH., Walz G. (2022)
  Nature Communications. Apr 19;13(1):2056.
• Notch signaling induces either apoptosis or cell fate change in multiciliated cells during mucociliary tissue remodeling.
  Tasca, A., Helmstädter, M., Brislinger, M.M., Haas, M., Mitchell, B., Walentek, P. (2021)
  Developmental Cell. Feb 22;56(4):525-539.e6.
• ΔN-Tp63 mediates Wnt/β-catenin-induced inhibition of differentiation in basal stem cells of mucociliary epithelia.
  Haas, M., Gómez Vázquez, J.L., Sun, D.I., Tran, H.T., Brislinger, M., Tasca, A., Shomroni, O., Vleminckx, K., Walentek, P. (2019)
  Cell Reports. Sep 24;28(13):3338-3352.e6.
• Manipulating and analyzing cell type composition of the Xenopus mucociliary epidermis.
  Walentek, P. (2018)
  Methods Mol Biol. 10.1007/978-1-4939-8784-9_18.
• Ciliary transcription factors and miRNAs precisely regulate Cp110 levels required for ciliary adhesions and ciliogenesis.
  Walentek, P., Quigley, I.K., Sun, D.I., Sajjan, U.K., Kintner, C., Harland, R.M. (2016)
  Elife. 10.7554/eLife.17557.
• miR-34/449 miRNAs are required for motile ciliogenesis by repressing cp110.
  Song, R.*, Walentek, P.*, Sponer, N.*, Klimke, A., Lee, J.S., Dixon, G., Harland, R., Wan, Y., Lishko, P., Lize, M., Kessel, M., He, L. (2014) (*co-first)
  Nature. 510, 115-20.
• A novel serotonin-secreting cell type regulates ciliary motility in the mucociliary epidermis of Xenopus tadpoles.
  Walentek, P., Bogusch, S., Thumberger, T., Vick, P., Dubaissi, E., Beyer, T., Blum, M, Schweickert, A. (2014)
  Development. 141, 1526-33.
• ATP4a is required for Wnt-dependent Foxj1 expression and leftward flow in Xenopus left-right development.
  Walentek, P., Beyer, T., Thumberger, T., Schweickert, A., Blum, M. (2012)
  Cell Reports. May 31;1(5):516-27 10.1016/j.celrep.2012.03.005.