@article{DohrmannEdgarSendtneretal.1986,
  author    = {Dohrmann, Ulrike and Edgar, David and Sendtner, Michael and Thoenen, Hans},
  title     = {Muscle-derived factors that support survival and promote fiber outgrowth from embryonic chick spinal motor neurons in culture},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-72862},
  year      = {1986},
  abstract  = {The purpose of the experiments reported is to provide an unambiguous demonstration that embryonie skeletal muscle contains factors that act directly on embryonie spinal motor neurons both to support their survival and to stimulate the outgrowth of neurites. Cells of lumbar and brachial ventral spinal cords from 6-day-old chick embryos were separated by centrifugation in a two-step metrizamide gradient, and a motor neuron enriched fraction was obtained. Motor neurons were identified by retrogradely labeling with rhodamine isothiocyanate, and were enriched fourfold in the motor neuron fraction relative to unfractionated cells. In culture, the isolated motor neurons died within 3-4 days unless they were supplemented with embryonie chick skeletal muscle extract. Two functionally distinct entities separable by ammonium sulfate precipitation were responsible for the effects of muscle extracts on motor neurons. The 0-25\% ammonium sulfate precipitate contained molecules that alone bad no effect on neuronal survival but when bound to polyornithine-coated culture substrata, stimulated neurite outgrowth and potentiated the survival activity present in muscle. Most of this activity was due to a laminin-like molecule being immunoprecipitated with antisera against laminin, and immunoblotting demonstrated the presence of both the A and B chains of laminin. A long-term survival activity resided in the 25-70\% ammonium sulfate fraction, and its apparent total and specific activities were strongly dependent on the culture substrate. In contrast to the motor neurons, the cells from the other metrizamide fraction (including neuronal cells) could be kept in culture for a prolonged time without addition of exogenous factor(s).},
  subject      = {Nervenzelle},
  language  = {en}
}
@article{SchartlHolsteinRobertsonetal.1989,
  author    = {Schartl, Manfred and Holstein, Thomas and Robertson, Scott M. and Barnekow, Angelika},
  title     = {Preferential expression of a pp60c-src related protein tyrosine kinase activity in nerve cells of the early metazoan Hydra (Coelenterates)},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-86179},
  year      = {1989},
  abstract  = {It has been suggested that the proto-oncogene c-src plays a functional role in developing neurons, and in the mature nerve cells of higher vertebrales. The coelenterate Hydra represents tbe most primitive known organism possessing nerve cells. With Southern blot hybridizations we have demonstrated src-related sequences in Hydra. Antisera specific for the c-src gene product (pp60 c-src) of birds and mammals precipitate a protein from Hydra cell extracts with a tyrosine-specific protein kinase activity. Studies of tissues and cells fractionated from a temperature sensitive mutant of Hydra which is depleted of interstitial (including nerve) cells at tbe non-permissive temperature, have indicated the src-like kinase of Hydra to be preferentially expressed in nerve cells. The high conservation of structural features and of the expression pattern indicates a basic function for pp60c-src in neurons.},
  subject      = {Protein-Tyrosin-Kinasen},
  language  = {en}
}