Evidence for a second isoform of the catalytic subunit of calmodulin-dependent protein phosphatase (calcineurin A).
We have used a previously characterized rat cDNA clone for the catalytic (A) subunit of calmodulin-dependent protein phosphatase (calcineurin), which we designated A alpha, to isolate cDNA clones coding for a second isoform of the A subunit, A beta. The A beta cDNA encodes a protein of 525 amino acids that is 81% identical with A alpha. The N-terminal region is dissimilar and contains a characteristic proline-rich sequence. The region homologous to protein phosphatases 1 and 2A (region between residues 87 and 338, 91% identical) and the calmodulin binding domain (region between residues 401 and 424, 96% identical) are highly conserved. The presence of two genes coding for calcineurin A suggests the possibility of important functional differences in the two enzymes.
Kuno
T
T
Department of Pharmacology, Kobe University School of Medicine, Japan.
Takeda
T
T
Hirai
M
M
Ito
A
A
Mukai
H
H
Tanaka
C
C
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D019703:Calcineurin; D002147:Calmodulin / Q000378:metabolism; D002148:Calmodulin-Binding Proteins / Q000235:genetics*; D004247:DNA / Q000235:genetics / Q000302:isolation & purification; D015342:DNA Probes; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D010749:Phosphoprotein Phosphatases / Q000235:genetics*; D051381:Rats; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid
D002147:Calmodulin; D002148:Calmodulin-Binding Proteins; D015342:DNA Probes; D004247:DNA; D019703:Calcineurin; D010749:Phosphoprotein Phosphatases