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Cyclic 3', 5'-AMP relay dictyostelium discoideum. V. Adaptation of the cAMP signaling response during cAMP stimulation
| Content Provider | Semantic Scholar |
|---|---|
| Author | Dinauer, Mary Steck, T. L. Devreotes, Peter N. |
| Copyright Year | 1980 |
| Abstract | In dictyostelium discoideum, extracellular cAMP activates adenylate cyclase, which leads to an increase in intracellular cAMP and the rate of cAMP secretion. The signaling response to a constant cAMP stimulus is terminated after several minutes by an adaptation mechanism. The time- course of adaptation stimuli of 10(-6) or 10(-7) M cAMP was assessed. We used a perfusion technique to deliver defined cAMP stimuli to [(3)H]adenosine-labeled amoebae and monitored their secretion of [(3)H]cAMP. Amoebae were pretreated with 10(-6) or 10(-7) M cAMP to periods of 0.33-12 minutes, and then immediately given test stimuli of 10(-8) M to 2.5 x 10(-7) M cAMP. The response to a given test stimulus was progressively attenuated and finally extinguished as the duration of the pretreatment stimulus increased. During concentration of the test stimulus. The responses to test stimuli of 10(-8), 5 x 10(-8), 10(-7), or 2.5 x 10(-7) M cAMP were extinguished after approximately 1, 2.25,2.5, and 10 min, respectively. 1.5 min of stimulation with 10(-7) M cAMP was necessary to extinguish the response of a test stimulus of 10(-8) M cAMP. Our data suggest that adaptation begins within 20 s of stimulation, rises rapidly for approximately 2.5 min, and reaches a plateau after approximately 10 min. The absolute rate of rise was faster during pretreatment with 10(-6) than with 10(-7) M cAMP. These results support a working hypothesis in which the occupancy of surface cAMP receptors leads to changes in two opposing cellular processes, excitation and adaptation, that control the activity of D. discoideum adenylate cyclase. |
| Starting Page | 554 |
| Ending Page | 561 |
| Page Count | 8 |
| File Format | PDF HTM / HTML |
| PubMed reference number | 6249827 |
| Volume Number | 86 |
| Journal | The Journal of cell biology |
| Alternate Webpage(s) | http://devreotes.johnshopkins.edu/sites/default/files/publications/019.pdf |
| Language | English |
| Access Restriction | Open |
| Subject Keyword | 8-chloro-cyclic adenosine monophosphate Acclimatization Adenylate Cyclase Dictyostelium discoideum Excitation Gonadotropin-Releasing Hormone Receptor Receptors, Cyclic AMP Relay Device Component Tracer |
| Content Type | Text |
| Resource Type | Article |
