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Heinrich Reichert

Publications and source records attributed to Heinrich Reichert.

2 recordsLinked to original sources

Identification and Functional Characterization of Muscle Satellite Cells in Drosophila

Work on genetic model systems such as Drosophila and mouse has shown that the fundamental mechanisms of myogenesis are remarkably similar in vertebrates and invertebrates. Strikingly, however, satellite cells, the adult muscle stem cells that are essential for the regeneration of damaged muscles in vertebrates, have not been reported in invertebrates. In this study we show role of Muscle stem cells (Gunage et al., 2014) identified in a previous study, in muscle regeneration. We show that muscle stem cells lineal descendants are present in adult muscle as small, unfused cells located superficially and in close proximity to the mature muscle fibers. Normally quiescent cells, following muscle fiber injury become mitotically active, engage in Notch-Delta signaling-dependent proliferative activity and generate lineal descendant populations, which fuse with the injured muscle fiber. In view of their strikingly similar morphological and functional features, we consider these novel cells to be Drosophila muscle satellite cells

Developmental Biology

Glial and neuronal Semaphorin signaling instruct the development of a functional myotopic map for Drosophila walking

Motoneurons developmentally acquire appropriate cellular architectures that ensure connections with postsynaptic muscles and presynaptic neurons. In Drosophila, leg motoneurons are organized as a myotopic map, where their dendritic domains represent the muscle field. Here we investigate mechanisms underlying development of aspects of this myotopic map, required for walking. A behavioral screen identified roles for Semaphorins (Serna) and Plexins (Plex) in walking behavior. Deciphering this phenotype, we show that PlexA/Sema1a mediates motoneuron axon branching in ways that differ in the proximal femur and distal tibia, based on motoneuronal birth order. Importantly, we show a novel role for glia in positioning dendrites of specific motoneurons; PlexB/Sema2a is required for dendritic positioning of late-born motoneurons but not early-born motoneurons. These findings indicate that communication within motoneurons and between glia and motoneurons, mediated by the combined action of different Plexin/Semaphorin signaling systems, are required for the formation of a functional myotopic map.

Developmental Biology