@article{BaumannSalvaterraTakeyasu2010,
  author    = {Baumann, Otto and Salvaterra, Paul M. and Takeyasu, Kunio},
  title     = {Developmental changes in beta-subunit composition of Na,K-ATPase in the Drosophila eye},
  issn      = {0302-766X},
  doi       = {10.1007/s00441-010-0948-x},
  year      = {2010},
  abstract  = {The Drosophila genome contains at least three loci for the Na,K-ATPase beta-subunit; however, only the protein products of nrv1 and nrv2 have been characterized hitherto. Here, we provide evidence that nrv3 also encodes for a functional Na,K-ATPase beta-subunit, as its protein product co-precipitates with the Na,K-ATPase alpha-subunit. Nrv3 expression in adult flies is restricted to the nervous system in which Nrv3 is enriched in selective types of sensory cells. Because Nrv3 expression is especially prominent in the compound eye, we have analyzed the subcellular and developmental distribution of Nrv3 within the visual cells and related this distribution to those of the alpha-subunit and of the beta-subunits Nrv1 and Nrv2. Prospective visual cells express Nrv2 in the third larval instar stage and during the first half of pupal development. During the last third of pupal life, Nrv3 gradually replaces Nrv2 as the Na,K-ATPase beta-subunit in the photoreceptor cells. Adult photoreceptors express Nrv3 as their major beta-subunit; the visual cells R1-R6 co-express Nrv2 at a low level, whereas R7 and R8 co-express Nrv1. Notably, beta-subunits do not co- distribute exactly with the alpha-subunit at some developmental stages, supporting the concept that the alpha-subunit and beta-subunit can exist in the plasma membrane without being engaged in alpha/beta heterodimers. The non-visual cells within the compound eye express almost exclusively Nrv2, which segregates together with the alpha-subunit to septate junctions throughout development.},
  language  = {en}
}
@article{SchulzBaumannSamereieretal.2009,
  author    = {Schulz, Irene and Baumann, Otto and Samereier, Matthias and Zoglmeier, Christine and Gr{\"a}f, Ralph},
  title     = {Dictyostelium Sun1 is a dynamic membrane protein of both nuclear membranes and required for centrosomal association with clustered centromeres},
  issn      = {0171-9335},
  doi       = {10.1016/j.ejcb.2009.06.003},
  year      = {2009},
  abstract  = {Centrosomal attachment to nuclei is crucial for proper mitosis and nuclear positioning in various organisms, and generally involves Sun-family proteins located at the inner nuclear envelope. There is still no common scheme for the outer nuclear membrane proteins interacting with Sun I in centrosome/nucleus attachment. Here we propose a model in which Sun1 mediates a physical link between centrosomes and clustered centromeres through both nuclear membranes in Dictyostelium. For the first time we provide a detailed microscopic analysis of the centrosomal and nuclear envelope localization of endogenous Dictyostelium Sun1 during interphase and mitosis. By immunogold electron microscopy we show that Sun1 is a resident of both nuclear membranes. Disruption of Sun1 function by overexpression of full-length GFP-Sun1 or a GFP-Sun-domain deletion construct revealed not only the established function in centrosome/nucleus attachment and maintenance of ploidy, but also a requirement of Sun1 for the association of the centromere cluster with the centrosome. Live-cell imaging visualized the occurrence of mitotic defects, and demonstrated the requirement of microtubules for dynamic distance changes between centrosomes and nuclei. FRAP analysis revealed at least two populations of Sun1, with an immobile fraction associated with the centrosome, and a mobile fraction in the nuclear envelope.},
  language  = {en}
}
@article{DubreuilGrushkoBaumann2001,
  author    = {Dubreuil, R. R. and Grushko, T. and Baumann, Otto},
  title     = {Differential effects of a labial mutation on the development, structure, and function of stomach acid-secreting cells in Drosophila larvae and adults},
  year      = {2001},
  language  = {en}
}
@article{Baumann2001,
  author    = {Baumann, Otto},
  title     = {Disruption of actin filaments causes redistribution of ryanodine receptor Ca2+ channels in honeybee photoreceptor cells},
  year      = {2001},
  language  = {en}
}
@article{ZimmermannDamesWalzetal.2003,
  author    = {Zimmermann, Bernhard and Dames, Petra and Walz, Bernd and Baumann, Otto},
  title     = {Distribution and serotonin-induced activation of vacuolar-type H+-ATPase in the salivary glands of the blowfly Calliphora vicina},
  year      = {2003},
  language  = {en}
}
@article{Baumann1997,
  author    = {Baumann, Otto},
  title     = {Distribution of Na+, K+-ATPase in photoreceptor cells of insects.},
  year      = {1997},
  language  = {en}
}
@article{Baumann2001,
  author    = {Baumann, Otto},
  title     = {Distribution of nonmuscle myosin-II in honeybee photoreceptor cells and its possible role in maintaining compound eye architecture},
  year      = {2001},
  language  = {en}
}
@article{Baumann2000,
  author    = {Baumann, Otto},
  title     = {Distribution of ryanodine receptor Ca2+ channels in insect photoreceptor cells},
  year      = {2000},
  language  = {en}
}
@article{BaumannDamesKuehneletal.2002,
  author    = {Baumann, Otto and Dames, Petra and K{\"u}hnel, Dana and Walz, Bernd},
  title     = {Distribution of serotonergic and dopaminergic nerve fibers in the salivary gland complex of the cockroach Periplaneta americana},
  year      = {2002},
  language  = {en}
}
@article{BaumannKuehnelDamesetal.2004,
  author    = {Baumann, Otto and K{\"u}hnel, Dana and Dames, Petra and Walz, Bernd},
  title     = {Dopaminergic and serotonergic innervation of cockroach salivary glands : distribution and morphology of synapses and release sites},
  year      = {2004},
  abstract  = {The paired salivary glands in the cockroach are composed of acini with ion-transporting peripheral P-cells and protein-secreting central C-cells, and a duct system for the modification of the primary saliva. Secretory activity is controlled by serotonergic and dopaminergic neurons, whose axons form a dense plexus on the glands. The spatial relationship of release sites for serotonin and dopamine to the various cell types was determined by anti-synapsin immunofluorescence confocal microscopy and electron microscopy. Every C-cell apparently has only serotonergic synapses on its surface. Serotonergic and dopaminergic fibres on the acini have their release zones at a distance of similar to0.5 mum from the P-cells. Nerves between acinar lobules may serve as neurohaemal organs and contain abundant dopaminergic and few serotonergic release sites. Some dopaminergic and serotonergic release sites reside in the duct epithelium, the former throughout the duct system, the latter only in segments next to acini. These findings are consistent with the view that C-cells respond exclusively to serotonin, P-cells to serotonin and dopamine, and most duct cells only to dopamine. Moreover, the data suggest that C-cells are stimulated by serotonin released close to their surface, whereas P-cells and most duct cells are exposed to serotonin/dopamine liberated at some distance},
  language  = {en}
}