German Society for Cell Biology International Meeting Report

By Peter Walentek

Peter Walentek is a postdoctoral fellow in Richard Harland's lab at the University of California, Berkeley.  He won the best postdoctoral presentation at the Hilde Mangold Postdoctoral Symposium at the Society for Developmental Biology 74th Annual Meeting in Snowbird, Utah.  His prize was a travel award to the meeting or course of his choice. Below is his report.

In March 2016 the annual International Meeting of the German Society for Cell Biology (DGZ) was held in Martinsried. The meeting took place at the new biomedical campus of Ludwig-Maximilians-University (LMU) just outside of Munich. This new home for most of LMU’s biological research groups is situated in close proximity to the University Hospital center Grosshadern as well as the Max-Planck-Institute for Biochemistry in Martinsried. Thus, the new campus is not only exciting because of its modern architecture, but also due to its location at the center of one of the main hubs for biomedical research in Germany.

Although I see myself mainly as a developmental biologist, I decided to use the generous Hilde Mangold award from the SDB to attend this meeting because my research on the formation and function of mucociliary epithelia is quite multidisciplinary and involves a lot of cell biology. I am using the Xenopus embryonic epidermis (which develops multiciliated and secretory cells) as a model for airway epithelia, and I am interested in the signaling and gene-regulatory networks that regulate development and regeneration of these epithelia. In order to understand the effects of manipulations on the epithelium as a whole, one must also understand the changes at the cellular level, e.g., how defects in morphogenesis of a specific cell type affect the function of the epithelium, and which translational consequences that might have in the context of chronic airway disease.

The meeting offered plenty of opportunity to dive into various topics on cell biology, including nuclear architecture, the role of the cytoskeleton in mechanosensing, and membrane trafficking, covered during plenary sessions; as well as topics ranging from RNA biology, to cell migration and adhesion, to the role of stem cells in regeneration, during concurrent sessions. One especially exciting plenary session focused on the relationship between nuclear architecture and gene regulation. Sandra Hake (LMU, Martinsried) presented some recent findings on the histone variant H2A.Z, which influences the transcriptional output of E2F regulated genes in human melanoma cells. Furthermore, experiments using Xenopus embryos suggest additional roles of this histone variant in vertebrate development. Michael Hannus (siTools, Martinsried) compared the RNAi and CRISPR/Cas9 methods, which both have some issues with off target effects that are hard to assess in routine experiments. Their new approach is to deliver a mix of siRNAs designed against a common target. This allows use of each individual siRNA at levels low enough to prevent off target effects, but in combination the target gene is efficiently depleted. This seems to be a clever use of the technology, which might be adapted to the CRISPR/Cas9 system or morpholino oligonucleotides as well. As the final speaker of the session, Ana Pombo (Max-Delbrueck Center for Molecular Medicine, Berlin) introduced a new method for genome architecture mapping, which is complementary to Hi-C studies and is being used to investigate three-dimensional chromosome folding and transcriptional regulation. Instead of fragmenting and re-ligating DNA in the tube to reveal DNA topology, this method uses DNA libraries from cryosections of nuclei. Interacting regions of the genome can be determined by analyzing libraries from many single nuclei samples, in which they are over represented in comparison to non-interacting regions.

Further personal highlights of the meeting include a talk by Roland Wedlich-Söldner (Institute of Cell Dynamics and Imaging, Muenster) on calcium-mediated reorganization of the cortical actin network. Upon mechanical stress, calcium is released and cortical actin relocates to the nuclear and ER membranes. This alters cell stiffness and behavior as well as gene expression in the simulated cell and even in neighboring cells. Another talk involving cytoskeletal regulation—this time during cytokinesis—by Esther Zanin (LMU, Munich) caught my attention. Using C. elegans embryos, she showed how amounts and localization of TPXL-1, which interacts with Aurora A kinase, regulate spindle positioning by influencing centrosomal microtubulin dynamics.

In addition to the great talks during plenary and concurrent sessions, two excellent poster sessions in the early afternoons offered opportunities to discuss the latest research findings and preliminary data from students and postdocs. In the late afternoons and evenings several keynote and award lectures were held, including a Carl Zeiss lecture by Thomas Pollard (Yale, New Haven) highlighting his lab’s seminal work on cytokinesis, and a Frontiers in Science lecture by Peter Becker (LMU, Martinsried) on the regulation of X chromosome dosage compensation in Drosophila by the MSL dosage compensation complex, and the roles of non-coding RNAs and RNA binding proteins within this complex.

Taken together, this was a great meeting to get the latest updates on the field of cell biology, which also highlighted the many ways researchers use embryonic model systems to address cell biological questions. Therefore, I am very grateful that the SDB allowed me to use the Hilde Mangold award to participate in this meeting and to visit the new LMU campus in Munich.