Isolation and immunohistochemical localization of a lectin-like molecule from the XXXX cerebellum.

@entity35 @entity3913 @entity6000
A lectin with a @entity3913 specificity was isolated from the cerebellum of young @entity35 . The method of purification was based on the observation that during homogenization of the tissue, the lectin binds to a class of @entity3913 -rich glycoproteins highly insoluble in Triton X-100. Sequential extractions in saline buffer devoid of, then containing, 0.5% @entity6000 allowed the elimination of a great part of other proteins. Using the same buffer containing 0.5 M @entity3913 , a specific class of protein can be solubilized. This fraction was enriched by affinity adsorption on insolubilized @entity3913 -rich glycoproteins followed by specific detachment with @entity3913 . One of the protein subunits, of molecular weight (MW) 130,000, was isolated by preparative gel electrophoresis. Upon re-electrophoresis, this compound gives two bands of MW 65,000 and 130,000, which appear to be a monomer and a dimer of a molecule called R1. Antibodies were raised against R1 which react with the monomer and the dimer and not against other proteins of the @entity35 cerebellum. The immunohistochemical localization of this lectin was performed in cerebella of 20-day-old rats. The antigen is concentrated in endothelial cells and in large and intermediate size neurons (Purkinje, Golgi, basket and deep nuclei neurons). Granule cell bodies are lightly stained and no label at all was found in glial cells. At the level of electron microscopy, the antigen was found to be very concentrated in multivesicular bodies and lysosomes of large neurons, on parts of the endoplasmic reticulum, on some mitochondrial outer membranes and on the plasma membrane of the dendrites. The possible role of this lectin in cerebella of young @entity35 is discussed in relation to its interaction with a specific class of @entity3913 -rich glycoproteins.
