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Regulatory differences among avian ecto-ATPases.

C Caldwell·V Norman·A Urbina·A Jarvis·C Quinonez·M Stemm·A S Dahms
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Abstract

Extracellular ATP is found to produce a variety of important biological responses. Ecto-ATPases are located on numerous cell types in many different species, regulate extracellular ATP levels and can be a key step in generating adenosine. Studies conducted on chicken ecto-ATPases from liver and cardiac and smooth muscle show a variety of differing properties including (1) different apparent Km's, (2) lectin sensitivity, (3) responses to detergents, (4) responses to lipid mediators, and (5) responsiveness to nucleotide-mimetic affinity labels. These results suggest that although each enzyme hydrolyzes extracellular ATP, they should each be viewed as a distinct subtype of the whole ecto-ATPase family due to their differential responses, largely linked to proposed regulatory phenomenon.

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Adenosine TriphosphatasesAdenosine TriphosphateAnimalsChickensConcanavalin ADetergentsDiacylglycerol KinaseErythrosineKineticsLipid MetabolismMicrosomes, LiverMuscle ProteinsMuscle, SmoothMyocardiumOctoxynolSolubilitySphingosineJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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C Caldwell, V Norman, A Urbina, A Jarvis, C Quinonez, M Stemm, A S Dahms. 1997-09-29. Regulatory differences among avian ecto-ATPases.. https://doi.org/10.1006/bbrc.1997.7377

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