Abstract |
In the human neuroblastoma cell line Lan-1, the mRNA encoding the Ca2+/ calmodulin (CaM) sensitive adenylyl cyclase type-1 (AC-1) was detected by reverse transcription-polymerase chain reaction (RT-PCR) as well as by Northern blotting. However, neither Ca2+/CaM stimulated AC activity was found nor could AC-1 type protein be detected by a specific antibody (anti-1Cl). In contrast, when cells were grown to high cell density, Ca2+/CaM stimulated AC-activity could be indeed found in membranes. The large increase in activity was paralleled by the appearance of a 110 kDa protein detected by the monoclonal AC antibody BBC-2. At the same time a 150 kDa adenylyl cyclase species present in growing cells was absent. The 110 kDa protein co-migrated with bovine AC-1 and was slightly larger than the human AC-1. Unexpectedly, however, the antibody anti-1CI was not able to precipitate the newly induced Lan-1 AC. In addition, no increase in type-1 AC mRNA could be detected either by PCR or by Northern blotting. Treatment of Lan-1 cells with 10 microM retinoic acid for 7 days caused growth arrest and morphological differentiation of the cells, yet the induction of the Ca2+/CaM-stimulated AC activity was much lower than in the dense grown control cultures. It is concluded that the Ca2+/CaM-activated AC of M(r) 110 kDa in Lan-1 cells is not related to the previously known Ca2+/CaM stimulated AC isoforms, and might thus represent a novel AC.
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Authors | F W Kluxen, A Hülster, M Droste, T Pfeuffer |
Journal | Brain research
(Brain Res)
Vol. 740
Issue 1-2
Pg. 169-74
(Nov 18 1996)
ISSN: 0006-8993 [Print] Netherlands |
PMID | 8973811
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Calmodulin
- Colforsin
- Adenylyl Cyclases
- Calcium
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Topics |
- Adenylyl Cyclases
(drug effects, metabolism)
- Animals
- Brain Neoplasms
(metabolism)
- Calcium
(pharmacology)
- Calmodulin
(pharmacology)
- Cattle
- Cell Count
- Colforsin
(pharmacology)
- Humans
- Neuroblastoma
(metabolism)
- Tumor Cells, Cultured
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