Formation and maturation of parallel fiber-Purkinje cell synapses in the Staggerer cerebellum ex vivo.
In vivo, homozygous staggerer (Rora(sg/sg)) Purkinje cells (PCs) remain in an early stage of development with rudimentary spineless dendrites, associated with a lack of parallel fiber (PF) input and the persistence of multiple climbing fibers (CFs). In this immunocytochemical study we used cerebellar organotypic cultures to monitor the development of Rora(sg/sg) PF-PC synapses in the absence of CF innervation. Ex vivo the vesicular glutamate transporters VGluT1 and VGluT2 reactivity was preferentially localized around the Rora(sg/sg) PC soma and proximal dendrites, which are typically CF domains. The shift from VGluT2 to VGluT1 in PF terminals during development was delayed in Rora(sg/sg) slices. The postsynaptic receptors mGluR1 and GluRdelta2 were differently distributed on Rora(sg/sg) PCs. mGluR1 reactivity was evenly distributed in PC soma and dendrites, whereas GluRdelta2 reactivity, normally restricted at PF synapses, was dense in Rora(sg/sg) PC somata. The presynaptic distribution of VGluT1 and VGluT2 on Rora(sg/sg) PCs matched the postsynaptic distribution of the glutamate receptor GluRdelta2, but not mGluR1.
Janmaat
Sonja
S
Department of Cell Biology, Molecular Imaging and Electron Microscopy, University Medical Center Groningen, University of Groningen, The Netherlands.
Frédéric
Florence
F
Sjollema
Klaas
K
Luiten
Paul
P
Mariani
Jean
J
van der Want
Johannes
J
D000818:Animals; D064026:Calbindins; D002531:Cerebellum / Q000166:cytology*; D007150:Immunohistochemistry; D051379:Mice; D008810:Mice, Inbred C57BL; D008818:Mice, Neurologic Mutants / Q000033:anatomy & histology / Q000502:physiology; D009412:Nerve Fibers / Q000378:metabolism / Q000648:ultrastructure*; D011689:Purkinje Cells / Q000166:cytology / Q000502:physiology; D017470:Receptors, Glutamate / Q000378:metabolism; D018094:Receptors, Metabotropic Glutamate / Q000378:metabolism; D064030:S100 Calcium Binding Protein G / Q000378:metabolism; D013569:Synapses / Q000502:physiology* / Q000648:ultrastructure; D046509:Tissue Culture Techniques; D050598:Vesicular Glutamate Transport Protein 1 / Q000378:metabolism; D050599:Vesicular Glutamate Transport Protein 2 / Q000378:metabolism
D064026:Calbindins; D017470:Receptors, Glutamate; D018094:Receptors, Metabotropic Glutamate; D064030:S100 Calcium Binding Protein G; D050598:Vesicular Glutamate Transport Protein 1; D050599:Vesicular Glutamate Transport Protein 2; C107913:glutamate receptor delta 2; C104077:metabotropic glutamate receptor type 1