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The "droso4schools" project aims to introduce the fruit fly "Drosophila" as a powerful modern teaching tool to convey curriculum-relevant specifications in biology lessons. Flies are easy and cheap to breed and have been at the forefront of biology research for a century, providing unique conceptual understanding of biology and exciting, memorable experiments that reflect relevant contemporary research. To provide adequate resources, PhD students worked as teaching assistants in partner schools to develop and test free-to-download sample lessons with support materials, two educational "YouTube" videos and a dedicated "droso4schools" website providing resources for lesson preparation, homework tasks and revision.

Dendrites represent arborising neurites in both vertebrates and invertebrates. However, in vertebrates, dendrites develop on neuronal cell bodies, whereas in higher invertebrates, they arise from very different neuronal structures, the primary neurites, which also form the axons. Is this anatomical difference paralleled by principal developmental and/or physiological differences? We address this question by focussing on one cellular model, motorneurons of Drosophila and characterise the compartmentalisation of these cells. We find that motorneuronal dendrites of Drosophila share with typical vertebrate dendrites that they lack presynaptic but harbour post-synaptic proteins, display calcium elevation upon excitation, have distinct cytoskeletal features, develop later than axons and are preceded by restricted localisation of Par6-complex proteins. Furthermore, we demonstrate in situ and culture that Drosophila dendrites can be shifted from the primary neurite to their soma, i.e. into vertebrate-like positions. Integrating these different lines of argumentation, we propose that dendrites in vertebrates and higher invertebrates have a common origin, and differences in dendrite location can be explained through translocation of neuronal cell bodies introduced during the evolutionary process by which arthropods and vertebrates diverged from a common urbilaterian ancestor. Implications of these findings for studies of dendrite development, neuronal polarity, transport and evolution are discussed. Keywords: Dendrite; Compartmentalisation; Mosaic analysis; Cytoskeleton; Transmitter receptors; Drosophila

Neurons in primary cell cultures provide important experimental possibilities complementing or substituting those in the nervous system. However, Drosophila primary cell cultures have unfortunate limitations: they lack either a range of naturally occurring cell types, or of mature physiological properties. Here, we demonstrate a strategy which supports both aspects integrated in one culture: Initial culturing in conventional serum-supplemented Schneider's medium (S[M.sup.20K]) guarantees acquisition of all properties known from 30 years of work on cell type-specific differentiation in this medium. Through subsequent shift to newly developed active Schneider's medium (S[M.sup.active]), neurons adopt additional mature properties like the ability to carry out plastic morphological changes, neurotransmitter expression and electrical activity. We introduce long-term FM-dye measurements as a tool for Drosophila primary cell cultures demonstrating the presence of increased, action potential-dependent synaptic activity in S[M.sup.active]. This is confirmed by patch-clamp recordings, which in addition show that S[M.sup.active]-cultured neurons display different spiking patterns. Furthermore, we demonstrate that transmission can be evoked in S[M.sup.active] cultures, revealing the existence of synaptic plasticity. Thus, these culture conditions support developmental, structural and physiological properties known or expected from the nervous system, enhancing possibilities for future experiments complementing or substituting those in nervous systems of Drosophila. Keywords: Cell lineage; Neural stem cells; Cell cultures; Synapse formation; Synaptic activity; Action potentials; Plasticity; FM dyes

Insect neurons are individually identifiable and have been used successfully to study principles of the formation and function of neuronal circuits. In the fruitfly Drosophila, studies on identifiable neurons can be combined with efficient genetic approaches. However, to capitalise on this potential for studies of circuit formation in the CNS of Drosophila embryos or larvae, we need to identify pre- and postsynaptic elements of such circuits and describe the neuropilar territories they occupy. Here, we present a strategy for neurite mapping, using a set of evenly distributed landmarks labelled by commercially available anti-Fasciclin2 antibodies which remain comparatively constant between specimens and over developmental time. By applying this procedure to neurites labelled by three Ga14 lines, we show that neuritic territories are established in the embryo and maintained throughout larval life, although the complexity of neuritic arborisations increases during this period. Using additional immunostainings or dye fills, we can assign Ga14-targeted neurites to individual neurons and characterise them further as a reference for future experiments on circuit formation. Using the Fasciclin2-based mapping procedure as a standard (e.g., in a common database) would facilitate studies on the functional architecture of the neuropile and the identification of candiate circuit elements. Keywords: Dendrites; Mapping; Neurites; Synapse; Development; Neurogenesis; Neuropeptides; Insects; Manipulations; Imaging

We have examined the role of integrins in the formation of the cell junctions that connect muscles to epidermis (muscle attachments) and muscles to neurons (neuromuscular junctions). To this end we have analyzed muscle attachments and neuromuscular junctions ultrastructurally in single or double mutant Drosophila embryos lacking PS1 integrin ([[Alpha].sub.PS1][[Beta].sub.PS]), PS2 integrin ([[Alpha].sub.PS2][[Beta].sub.PS]), and/or their potential extracellular ligand laminin A. At the muscle attachments PS integrins are essential for the adhesion of hemiadherens junctions (HAJs) to extracellular matrix, but not for their intracellular link to the cytoskeleton. The PS2 integrin is only expressed in the muscles, but it is essential for the adhesion of muscle and epidermal HAJs to electron dense extracellular matrix. It is also required for adhesion of muscle HAJs to a less electron dense form of extracellular matrix, the basement membrane. The PS1 integrin is expressed in epidermal cells and can mediate adhesion of the epidermal HAJs to the basement membrane. The ligands involved in adhesion mediated by both PS integrins seem distinct because adhesion mediated by PS1 appears to require the extracellular matrix component laminin A, while adhesion mediated by PS2 integrin does not. At neuromuscular junctions the formation of functional synapses occurs normally in embryos lacking PS integrins and/or laminin A, but the extent of contact between neuronal and muscle surfaces is altered significantly. We suggest that neuromuscular contact in part requires basement membrane adhesion to the general muscle surface, and this form of adhesion is completely abolished in the absence of laminin A. Key Words: adhesion; Drosophila; extracellular matrix; integrin; laminin; neuromuscular junction.

We report the embryonic phenotype of muscleblind (mbl), a recently described Drosophila gene involved in terminal differentiation of adult ommatidia. mbl is a nuclear protein expressed late in the embryo in pharyngeal, visceral, and somatic muscles, the ventral nerve cord, and the larval photoreceptor system. All three mbl alleles studied exhibit a lethal phenotype and die as stage 17 embryos or first instar larvae. These larvae are partially paralyzed, show a characteristically contracted abdomen, and lack striation of muscles. Our analysis of the somatic musculature shows that the pattern of muscles is established correctly, and they form morphologically normal synapses. Ultrastructural analysis, however, reveals two defects in the terminal differentiation of the muscles: inability to differentiate Z-bands in the sarcomeric apparatus and reduction of extracellular tendon matrix at attachment sites to the epidermis. Failure to differentiate both structures could explain the partial paralysis and contracted abdomen phenotype. Analysis of mbl expression in embryos that are either mutant for Dmef2 or ectopically express Dmef2 places mbl downstream of Dmef2 function in the myogenic differentiation program. mbl, therefore, may act as a critical element in the execution of two Dmef2-dependent processes in the terminal differentiation of muscles. Key Words: muscleblind; Z-bands; muscle attachments; myogenesis; Drosophila.

A novel protein of cellular septate junctions was localized and characterized as a member of the Drosophila neurexin gene family. Neurexin IV (NRX) is a synapse-specific extracellular protein encoded by the nrx gene for cell adhesion. The role of NRX protein in neuromuscular communication was also exhibited in the Drosophila embryos with nrx gene mutations which exhibited reduced coordination of muscle propagation waves and defective neuronal connections.

Die fortschreitende Digitalisierung führt auch in Justiz und Straffälligenhilfe zu einer ver- stärkten Beschäftigung mit internetbasierten Angeboten. Ein Beispiel ist das für straf- fällig gewordene junge Menschen entwickelte Online-Training „CLICK!“ von Drudel 11 e.V. Das Training bietet eine zeitgemäße und zielgruppengerechte Möglichkeit pädago- gischer Intervention. Thematisch geht es in dem modular aufgebauten Programm vor allem um die Auseinandersetzung mit Gewalt und Rechtsextremismus. Solche digitalen Präventions- und Interventionsmaßnahmen sind in Deutschland noch wenig verbreitet und empfehlen sich nicht nur in der Pandemiesituation, sondern auch aufgrund der mit diesem Ansatz und im Beitrag beschriebenen strukturellen und methodischen Chancen. [ABSTRACT FROM AUTHOR]