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Cloning of human calcineurin A: evidence for two isozymes and identification of a polyproline structural domain.
- Source :
- Proceedings of the National Academy of Sciences of the United States of America; December 1989, Vol. 86 Issue: 23 p9183-9187, 5p
- Publication Year :
- 1989
-
Abstract
- Two types (I and II) of cDNAs encoding the large (A) subunit of calcineurin, a calmodulin-regulated protein phosphatase, were isolated from human basal ganglia and brainstem mRNA. The complete sequences of the two calcineurin clones are identical except for a 54-base-pair insert in the type I clone and different 3' ends including part of the coding sequence for the C termini of the two proteins. These findings suggest that calcineurin A consists of at least two isozymes that may result from alternative splicing events. The two forms of the enzyme differ in the C terminus, which contains an inhibitory domain rapidly severed by limited proteolysis. With the exception of an 18-amino acid insert, the central parts of the molecules, which harbor the catalytic domains, are identical and show extended similarities with the entire catalytic subunits of protein phosphatases 1 and 2A, defining a distinct family of protein phosphatases. The 40-residue N-terminal fragment, specific for calcineurin, contains a sequence of 11 successive prolines that is also found in bovine brain calcineurin by peptide sequencing. A role in the calmodulin activation of calcineurin is proposed for this novel structural element.
Details
- Language :
- English
- ISSN :
- 00278424 and 10916490
- Volume :
- 86
- Issue :
- 23
- Database :
- Supplemental Index
- Journal :
- Proceedings of the National Academy of Sciences of the United States of America
- Publication Type :
- Periodical
- Accession number :
- ejs60419992
- Full Text :
- https://doi.org/10.1073/pnas.86.23.9183