Detection of a beta-parvalbumin isoform in the mammalian inner ear.
A small, acidic calcium-binding protein (CBP-15) has been detected in the guinea pig organ of Corti, the auditory receptor organ. The apparent molecular weight (15,000) and very low isoelectric point (pI approximately 3.1) suggest that CBP-15 is a beta-parvalbumin isoform. Consistent with this hypothesis, CBP-15 exhibits extreme homology to the mammalian oncofetal parvalbumin called oncomodulin. Sequence data have now been obtained for 30 residues in the N-terminal third of CBP-15. Identity with oncomodulin is observed at all 30 positions. This finding could necessitate revision of the assumption that postnatal mammals utilize a single alpha-parvalbumin isoform in muscle and nonmuscle settings alike.
Thalmann
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I
Department of Otolaryngology, Washington University School of Medicine, St. Louis, MO 63110, USA.
Shibasaki
O
O
Comegys
T H
TH
Henzl
M T
MT
Senarita
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M
Thalmann
R
R
D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D002118:Calcium / Q000378:metabolism; D006168:Guinea Pigs; D007526:Isoelectric Point; D008969:Molecular Sequence Data; D008970:Molecular Weight; D018482:Muscle, Skeletal / Q000378:metabolism; D009925:Organ of Corti / Q000737:chemistry*; D010320:Parvalbumins / Q000032:analysis* / Q000737:chemistry; D017421:Sequence Analysis; D017385:Sequence Homology; D012697:Serine Endopeptidases / Q000378:metabolism
D010320:Parvalbumins; D012697:Serine Endopeptidases; C028344:glutamyl endopeptidase; D002118:Calcium