The Acetylcholinesterase from Drosophila Melanogaster
Acetylcholinesterase, the enzyme which hydrolyses acetylcholine, is a key component of the cholinergic system. In Drosophila melanogaster as in other animals the enzyme is membrane bound.1 The enzyme from the eel Electrophorus electricus has been well studied.2 Various molecular forms of the enzyme are known. All of these have a multisubunit head connected to a fibrous tail. Dudai3 has shown that in Drosophila melanogaster the enzyme exists in three forms which have sedimentation coefficients of 7S, 11S and 16S. The subunit structure of acetylcholinesterase in Drosophila melanogaster has not yet been studied. We have labelled the enzyme in its membrane environment in the particulate fraction of the brain cells with tritiated diisopropylfluorophosphate (DFP) and examined the electrophoretic behavior of the labelled components by SDS-PAGE.In addition, Triton X-100 extracts of the particulate fraction have been fractionated on Sephadex G-200 to determine the smallest unit with which enzyme activity is associated and to confirm the polyacrylamide gel electrophoresis data.
KeywordsParticulate Fraction Complete Reduction Membrane Fragment Sedimentation Coefficient Radioactivity Distribution
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