Expression of the immunoglobulin superfamily neuroplastin adhesion molecules in adult and developing mouse cerebellum and their localisation to parasagittal stripes.
Neuroplastin (np) 55 and 65 are immunoglobulin superfamily members that arise by alternative splicing of the same gene and have been implicated in long-term activity-dependent synaptic plasticity. Both biochemical and immunocytochemical data suggest that np55 is the predominant isoform (>95% of total neuroplastin) in cerebellum. Neuroplastin immunoreactivity is concentrated in the molecular layer and synaptic glomeruli in the granule cell layer. Expression in the molecular layer appears to be postsynaptic. First, neuroplastin is associated with Purkinje cell dendrites in two mouse granuloprival cerebellar mutants, disabled and cerebellar deficient folia. Second, in an acid sphingomyelinase knockout mouse with widespread protein trafficking defects, neuroplastin accumulates in the Purkinje cell somata. Finally, primary cerebellar cultures show neuroplastin expression in Purkinje cell dendrites and somata lacking normal histotypic organization and synaptic connections, and high-magnification views indicate a preferential association with dendritic spines. In the molecular layer, differences in neuroplastin expression levels present as a parasagittal array of stripes that alternates with that revealed by the expression of another compartmentation antigen, zebrin II/aldolase c. Neuroplastin immunoreactivity is first detected weakly at postnatal day 3 (P3) in the anterior lobe vermis. By P5, parasagittal stripes are already apparent in the immature molecular layer. At this stage, punctate deposits are also localised at the perimeter of the Purkinje cell perikarya; these are no longer detected by P15. The data suggest a role for neuroplastins in the development and maintenance of normal synaptic connections in the cerebellum.
Marzban
Hassan
H
Department of Cell Biology and Anatomy, Genes and Development Research Group, Faculty of Medicine, University of Calgary, Calgary, Alberta T2N 4N1, Canada.
Khanzada
Umme
U
Shabir
Saima
S
Hawkes
Richard
R
Langnaese
Kristina
K
Smalla
Karl-Heinz
KH
Bockers
Tobias M
TM
Gundelfinger
Eckart D
ED
Gordon-Weeks
Phillip R
PR
Beesley
Philip W
PW
D000818:Animals; D015153:Blotting, Western; D015815:Cell Adhesion Molecules / Q000032:analysis*; D002525:Cerebellar Cortex / Q000737:chemistry; D002531:Cerebellum / Q000737:chemistry* / Q000254:growth & development; D046508:Culture Techniques; D004591:Electrophoresis, Polyacrylamide Gel; D005455:Fluorescent Antibody Technique; D007124:Immunoenzyme Techniques; D007136:Immunoglobulins / Q000032:analysis*; D051379:Mice; D008818:Mice, Neurologic Mutants; D009474:Neurons / Q000737:chemistry*; D013569:Synapses / Q000737:chemistry*
D015815:Cell Adhesion Molecules; D007136:Immunoglobulins