Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.5.1.52 (PNGase F)
 1,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A monoclonal antibody (mAb), 2E12, against the neural cell adhesion molecule L1 recognized the 200 kDa component of L1. The epitope of L1 reacting with mAb 2E12 was localized in its carbohydrate chain, judging from the results of experiments on glycopeptidase F treatment. The physiological effect of adding mAbL1 (2E12) to cultured mouse dorsal root ganglion neurons was studied using patch-clamp techniques. The binding of mAbL1 (2E12) to the neurons expressing L1 molecule induced an inward current inhibited by calcium channel blockers such as nifedipine and Lanthanum. It was also found that the mAbL1 (2E12) leads to a rise in the intracellular Ca2+ concentration ([Ca2+]i) in cultured neurons. This rise seems to be due to an influx of extracellular Ca2+, since treatment with EGTA abolished those phenomena. L-type calcium channel blockers such as nifedipine and cadmium, as well as inward current, blocked the effect of mAbL1 (2E12). These results suggest that the carbohydrate chain of L1 glycoprotein is directly involved in the induction of calcium current, and that the L1 molecule may play a prominent role in regulation of the Ca2+ channel.
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PMID:Monoclonal antibody that recognizes the carbohydrate portion of cell adhesion molecule L1 influences calcium current in cultured neurons. 138 50

Primary cardiac cell cultures of newborn rats containing approximately 50% (by cell number) spontaneously contracting cardiomyocytes were used to study the role of protein N-glycosylation for the binding of dihydropyridine (DHP) to the voltage-dependent L-type calcium channel. This binding is not influenced by the accompanying non-muscle cells. Exposure of the cells up to 6 micrograms/ml of the N-glycosylation inhibitor tunicamycin for a 44 h period resulted in a decrease of the specific DHP binding sites (Bmax) to 46.0 +/- 17.2% of the untreated control. Similar effects were observed after enzymatic deglycosylation using N-glycosidase F (PNGase F). The results suggest that a posttranslational modification of parts of the cardiac L-type Ca+2 channel by N-glycosylation is an important determinant for the binding of Ca+2 antagonists of the DHP-type to the alpha 1 subunit which itself is not glycosylated. The results suggest a participation of N glycosylation in the assembling of the subunits to the functional channel and/or its turnover. However, a possible effect of tunicamycin on the expression of the Ca channel as an alternative mechanism cannot be excluded.
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PMID:Primary cultures of cardiac muscle cells as models for investigation of protein glycosylation. 890 53