engleski

Relationship of gangliosides and neuroplastin is important for synaptic membrane organization and function

Cellular membranes are not merely inert lipid bilayers wrapping cells, but present as lively structures adapting to changes in extracellular environment in many fascinating ways. Precise regulation of membrane dynamics is especially important for the organization and function of synaptic membranes in mammalian brain. As specific alterations of membrane organization have been reported in many human diseases, significant attention has been drawn to the field of (glyco)lipidomics. Our previous findings, in conjunction with the results of other groups, confirmed that changes in composition and metabolism, especially degradation of glycosphingolipids, contribute to complex pathogenesis of neurodegeneration. Our recent research is focused on analyzing the effects of changed membrane lipid composition on the expression and functions of membrane proteins in mammalian brain. We are particularly interested in relationship of gangliosides, membrane lipids highly abundant in brain tissue, and transmembrane glycoprotein neuroplastin, cell-adhesion molecule involved in synaptic plasticity. Using knockout mouse models with characteristic phenotype carrying different neurological abnormalities due to altered ganglioside biosynthesis, we confirmed that specific brain ganglioside pattern influences neuroplastin expression. Analysis of neuroplastin in brain tissue of knockout and wild-type mice revealed changed neuroplastin gene and protein expression, but also substantially different distribution of neuroplastin immunoreactivity in the hippocampi of mice that lack complex ganglioside structures. Most prominent difference in neuroplastin immunoreactivity was found in the pyramidal layers of CA1 and CA3, which are involved in basic hippocampal circuitry. Having in mind reported roles of neuroplastin in behavior and disease, it is tempting to investigate further the exact nature of relationship of gangliosides and neuroplastin and its importance for proper functioning of synaptic membranes.

Gangliosides; neuroplastin; synaptic membrane

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