Developmental and Cell Biology
Research in the Unit for Developmental Biology is focused on fundamental processes of animal or plant development, evolution and disease, which are addressed in genetic model organisms, such as zebrafish, mouse, Drosophila and satellite insect models like the red flour beetle Tribolium, or Arabidopsis. Studied cellular processes range from cell differentiation, proliferation, survival or death to cell adhesion, motility and invasiveness, focusing on the contribution of such cellular processes on events like tissue patterning, morphogenesis and homeostasis.
Based on their former work on the different roles of Bone Morphogenetic Proteins (BMPs) signaling during dorsoventral patterning of the gastrulating zebrafish embryo, the group of Professor Hammerschmidt now studies later processes of zebrafish development and disease with potential biomedical relevance: (1) Skin development, homeostasis, carcinogenesis and regeneration; (2) Bone development and disease; (3) Neuroendocrine control of energy homeostasis and somatic growth. Numerous systematic approaches are used to identify essential regulators of these different processes and to elucidate their functional mechanisms, such as phenotype-based forward genetic screens after chemical or insertional mutagenesis and identification of the causative DNA lesions via whole genome sequencing, transcriptomics and proteomics, followed by reverse genetics (TALEN and CRISPR/Cas9 technology) to generate mutants in the identified candidates, as well as transgenesis for temporally and spatially controlled overexpression and cell ablation studies.
The group of Professor Roth is working on the evolution of axis formation and gastrulation in insects with a particular focus on the dorsoventral (DV) axis. Earlier work from the Roth group with Drosophila showed how EGF signaling during oogenesis polarizes the egg along the DV axis and how Toll and BMP signaling during embryogenesis specify different cell types long the embryonic DV axis. To understand how axis formation has evolved the Roth group now concentrates on other insects for which genomic tools and functional manipulations are available like the red flour beetle Tribolium castaneum, the wasp Nasonia vitripennis, the milkweed bug Oncopeltus fasciatus and cricket Gryllus bimaculatus. The aim of the work is a deeper understanding of the mechanisms by which the role of signaling pathways and the architecture of gene regulatory networks change during evolution. We are particularly interested in finding out how Toll signaling, which had an ancestral immune function was recruited for axis formation during insects evolution. We apply transcriptomics, ChIPseq, transgenesis, gene knockdown by RNAi, CRISPR/cas mediated genome editing and live imaging to reconstruct gene regulatory networks and understand the role of individual network components for cell specification and morphogenesis.
The Emmy Noether group headed by Dr. Panfilio focuses on embryonic development in multiple species of insects as excellent models to investigate both (a) epithelial tissue morphogenesis and (b) molecular evolution and comparative genomics across macroevolutionary time scales. Extraembryonic tissues dynamically envelop and protect the embryo. To do so, these epithelial tissue sheets exhibit many cell shape change and tissue remodeling behaviors that are typical of animal development. We explore their activity and genetic regulation through functional, live imaging investigations, primarily in the flour beetle Tribolium castaneum. For example, this work includes light sheet fluorescence microscopy recordings for time-lapse and three-dimensional reconstruction applications, for both wild type, healthy development and RNA interference treatments. At the same time, we focus on the milkweed bug, Oncopeltus fasciatus, as an experimentally tractable model for comparative genomics investigations of the Hemiptera, the largest order of hemimetabolous insects. For both of these research areas, our main aim is to understand the underlying patterns and regulatory control that strike a balance between species-specific features and robust development.
Professor Werr´s group is engaged in the development of Arabidopsis thaliana. Starting from the single-celled zygote, a stereotypic pattern of cell divisions in Arabidopsis thaliana establishes the plant body axes and the anlagen of the shoot apical meristem (SAM) or the basal root meristem (RM). A major focus is SAM function and a combination of genetic, molecular and cell biological approaches is pursued to identify and unravel the regulatory networks underlying founder cell specification for lateral organ primordia in the peripheral zone of the SAM. A second approach releates to stem cell identity and homeostasis, where WUSCHEL (WUS), the founding member of the WUSCHEL related homeobox (WOX) gene family, promotes stem cell fate in the SAM and WOX5, its closest relative, contributes a similar function in the root. Given the importance of meristems for plant growth an open question was when these stem cell promoting functions originated in the course of plant evolution and phylogenetic reconstructions revealed plesiomorphies to the base of seed plants; apparently gymno- and angiosperms share a common ancestor that had invented multiple independent stem cell niches.
Other groups within the Institute for Zoology working on Developmental Biology are:
AG PD Benjamin Altenhein (Unit Neuroanatomy / Experimental Morphology):
- Neural development in Drosophila
AG PD Michael Kroiher (Unit Neuroranatomy / Experimental Morphology):
- Development and evolution of nematodes