Function of ganglioside 9-O-acetyl GD3 in neuronal migration

FUNCTION OF GANGLIOSIDE 9-O-ACETYL GD3 IN NEURONAL MIGRATION^*

MARCELO F. SANTIAGO, MARCIA BERREDO-PINHO, MARIO GANDRA, LENY A. CAVALCANTE AND ROSALIA MENDEZ-OTERO

Instituto de Biofísica Carlos Chagas Filho Universidade Federal do Rio de Janeiro, 21941-590 Rio de Janeiro, RJ, Brazil.

Neuronal migration occurs in many regions of the developing mammalian central nervous system and normal histogenesis is dependent on the precise migration of neurons during development. In the cerebellum, granule cell precursors migrate along tangential paths from the most caudal portion of the cerebellar ventricular zone onto the surface of the cerebellum where they form the external granular layer (EGL). During the early postnatal period in rodents, granule cells in the proliferative EGL migrate down into the cerebellar cortex to form the internal granular layer (IGL). It has been proposed that granule cells use the processes of radial glia to migrate from the EGL to the IGL. Although several molecules have been proposed to be involved in this process the molecular mechanisms influencing granule cell migration are not yet fully understood. In the present study, we provide evidence that the ganglioside 9-O-acetyl GD3 recognized by the monoclonal antibody Jones (Jones mAb) is involved in the migration of granule cells in the developing rat cerebellum. Gangliosides constitute a major group of cell-surface molecules that have been implicated in numerous functions in the developing and adult mammalian nervous system. The expression of 9-O-acetyl GD3 correlates specifically with times of granule cell migration in the cerebellum suggesting a possible role for this molecule in the glial-guided migration of these cells. Electron microscopic immunocytochemistry revealed that this ganglioside was localized at the contact sites between migrating granule neurons and radial glia in the external granule layer and prospective molecular layer. To investigate the function of 9-O-acetyl GD3 in this system we added Jones mAb to cerebellar cultures. It was possible to demonstrate that granule cell migration was blocked in the presence of the antibody. Our results suggest that 9-O-acetyl GD3 is involved in neuronal migration. — ( June 27, 2000 )

*

Supported by PRONEX/MCT, CNPq, FAPERJ, CEPG/UFRJ.

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Publication Dates

• Publication in this collection
  05 Oct 2000
• Date of issue
  Sept 2000