Myosin-Va is a molecular motor that may participate in synaptic vesicle cycling. Calpain cleaves myosin-Va in vitro at methionine 1141 in the tail domain. We show that intracellular proteolysis of myosin-Va occurs in rat cortical synaptosomes depolarized in the presence of calcium, evidenced by the formation of an 80 k polypeptide that co-migrates in SDS-PAGE with the 80 k fragment produced by ...

1. Introduction tosomal fractions was also checked by electron microscopy. Synaptosome isolation methods should meet two principal but contradicting requirements: The fraction should be enriched as much as possible in synap tosomes, while the amount of time used during the isolation process should be as short as possible. The conditions of synaptosomal preparation and the duration of each step ...

1. The subcellular distributions of glutamate decarboxylase and aspartate transaminase were studied in rat and guinea-pig brain. 2. Glutamate decarboxylase is localized in the synaptosome fraction. The mean density of the particles containing the enzyme is slightly greater than those derived from cholinergic neurones, though overlap is substantial. 3. The enzyme is readily released from synapto...

Abstract Background Mitochondrial dysfunction is a critical factor in the onset and progression of neurodegenerative diseases. Recently, mitochondrial transplantation has been advised as an innovative attractive strategy to transfer replace damaged mitochondria. Here we propose, for first time, use rat brain extracted synaptosomes, subcellular fraction isolated synaptic terminal that contains m...

The Sec1 family of proteins is proposed to function in vesicle trafficking by forming complexes with target membrane SNAREs (soluble N-ethylmaleimide-sensitive factor [NSF] attachment protein [SNAP] receptors) of the syntaxin family. Here, we demonstrate, by using in vitro binding assays, nondenaturing gel electrophoresis, and specific neurotoxin treatment, that the interaction of syntaxin1A wi...

Synaptic vesicle fusion is driven by the formation of a four-helical bundle composed of soluble N-ethylmaleimide sensitive factor (NSF) attachment protein receptors (SNAREs). Exactly how the structural interactions that lead to the formation of this complex relate to neurotransmitter release is not well understood. To address this question, we used a strategy to "rescue" synaptic transmission a...

A synaptosomal ATP-dependent Ca uptake system was reconstituted into artificial vesicles by a cholate dialysis procedure using an 80-fold excess of exogenous phospholipid. Under these conditions, most of these vesicles would be expected to have only one or, at most, a few membrane proteins. The vesicles containing an ATP-dependent Ca transport system were purified from the bulk of the preparati...

Presynaptic N-type calcium channels interact with syntaxin and synaptosome-associated protein of 25 kDa (SNAP-25) through a binding site in the intracellular loop connecting domains II and III of the alpha1 subunit. This binding region was loaded into embryonic spinal neurons of Xenopus by early blastomere injection. After culturing, synaptic transmission of peptide-loaded and control cells was...