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Müller glia cells and their possible roles during retina differentiation
in vivo and in vitro
E. Willbold and P.G. Layer
Technische Universität Darmstadt, Institut für
Zoologie, Darmstadt, Germany
Offprint requests to: Elmar
Willbold, Technische Universität Darmstadt Institut für Zoologie,
Schnittspahnstraße 3, 64287 Darmstadt, Germany
Summary. Müller cells
are astrocyte-like radial glia cells which are formed exclusively in the
retina. Here we present evidence that Müller cells are crucially involved
in the development of the retina's architecture and circuitry. There is
increasing evidence that Müller cells are present from the very early
beginning of retino-genesis. We postulate the "gradual maturation hypothesis
of Müller cells". According to this hypothesis, Müller cells
are continuously generated by a gradual transition of neuroepithelial stem
cells into mature Müller cells. This process may be partly reversible.
Müller cells, or their immature precursors, are able to subserve different
functions. They are primary candidates for stabilizing the complex retinal
architecture and for providing an orientation scaffold. Thereby, they introduce
a reference system for the migration and correct allocation
of neurons. Moreover, they may provide spatial information
and microenvironmental cues for differentiating neurons, and may also be
important for the segregation of cell and fibre layers. Additionally, they
seem to be involved in the guidance of axonal fibres both in radial and
in lateral directions, as they are involved in the support and stabilization
of synapses. Histol Histopathol 13, 531-552 (1998)
Key words: Müller cells,
Radial glia, Retina, Development, Pigmented epithelium, Chick, Rotation
culture, Chick-quail chimeras, F11
DOI: 10.14670/HH-13.531
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