Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:O95477 (membrane-bound)
 29,236 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities in the neural retina and retinal pigment epithelium (RPE) of adult rats were determined. The tissues were extracted with a saline buffer to release the soluble enzymes (S1) and the pellet re-extracted with Triton X-100 to detach the membrane-bound enzymes (S2). Less than 5% of the cholinesterase activity measured in retina and almost 30% of that assayed in RPE was due to BChE. About 20% and 10% of the AChE in retina and RPE was brought into solution with a saline buffer and the rest with a detergent-containing buffer. Main AChE molecular forms of 10.5S (hydrophilic G4H), 9.5S (amphiphilic G4A) and 3.0S (amphiphilic G1A) were identified in retina by subjecting the supernatant S1 to sedimentation analysis in sucrose gradients made with Brij 96. Amphiphilic G4 and G1 AChE were found in S2. Analysis of the soluble fractions obtained from RPE in the gradients made with Brij 96 revealed 16.0S (asymmetric A12), 10.5-10.0S (globular G4H + G4A), 4.5S (G2A), and 3.0S (G1A) AChE forms in S1, whereas G4A, G2A, and G1A enzyme molecules predominated in S2. Our results show that amphiphilic tetramers and monomers of AChE are abundant in neural retina, and enzyme tetramers, dimers, and monomers in RPE. The AChE in the neural retina might be involved in cholinergic actions. The enzyme function in the retinal pigment epithelium remains to be established.
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PMID:Acetyl- and butyrylcholinesterase activities in the rat retina and retinal pigment epithelium. 756 46

We show that in the central nervous system of the fly, Drosophila melanogaster, choline acetyltransferase (ChAT) activity exists under two molecular forms, a soluble, hydrophilic form and a membrane-bound, amphiphilic form. This is based on the following demonstrations of differential solubilization and interaction with non-denaturing detergents: sequential extraction of Drosophila heads produced low-salt-soluble (83-87%) and detergent-soluble (6-7%) ChAT activity. Sedimentation in sucrose gradients of detergent-soluble ChAT was found to be influenced by the type of detergent present in the gradient (Triton X-100 and Brij 96). This was not the case for low-salt-soluble ChAT. To further confirm these findings, we subjected Drosophila heads to Triton X-114 fractionation. This method, which yielded 12% of amphiphilic ChAT activity, separates hydrophilic from amphiphilic proteins. Compared to central nervous tissue of rat and Torpedo electric lobes, Drosophila head contained the highest proportion of amphiphilic ChAT activity. Synaptosomes isolated from Torpedo electric organ exhibited higher levels of amphiphilic ChAT than did electric lobes. Of the three animal species analyzed here, the Torpedo amphiphilic enzyme was the most hydrophobic and the rat enzyme the least hydrophobic. The proportion of amphiphilic ChAT was analyzed during Drosophila development. The percentage of this activity increased about 7 times from embryo to larva and then remained constant until the adult fly age.
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PMID:The proportion of amphiphilic choline acetyltransferase in Drosophila melanogaster is higher than in rat or Torpedo and is developmentally regulated. 850 6