Protein synthesis at the synapse: developmental changes, subcellular localization and regional distribution of polypeptides synthesized in isolated dendritic fragments

This study evaluated local protein synthesis in subcellular fractions of pi nched-off dendrites (synaptodendrosomes) from different brain regions and a t different developmental ages. Synaptodendrosomes were labeled with [S-35] methionine and newly synthesized proteins were characterized by SDS-PAGE an d phosphorimaging. The same set of approximately 30 cycloheximide-sensitive labeled bands was observed in synaptodendrosomes isolated from different b rain regions, although the relative enrichment of some individual bands var ied. Labeling of several major proteins was developmentally regulated, reve aling three different patterns of variation. Subcellular fraction studies r evealed that at least 10 labeled bands were enriched in synaptic junctions. (C) 2001 Elsevier Science B.V. All rights reserved.