Purification, characterization, and partial sequence analysis of 32-kDa calcimedin from chicken gizzard.
Calcimedin is a group of proteins which has a binding ability to several hydrophobic matrices or cellular membrane fractions in the presence of Ca2+. Although the molecular properties were partially clarified, the physiological functions of calcimedins have not been clearly defined. In this study, we describe the isolation and characterization of 32-kDa calcimedin from chicken gizzard. Both structural and functional studies establish that 32-kDa calcimedin is a member of the calpactin/lipocortin family. The 32-kDa calcimedin displays phospholipase A2 inhibitory activity, Ca2(+)-dependent F-actin binding activity, and phospholipid binding activity similar to those of calpactins/lipocortins. Antiendonexin II antibody recognized 32-kDa calcimedin. However, antibodies against calpactin I (lipocortin II), calpactin II (lipocortin I), 35-kDa calcimedin, and 67-kDa calcimedin did not cross-react with 32-kDa calcimedin. One-dimensional peptide maps of the 32-kDa calcimedin and the 35-kDa calcimedin are different, confirming that they are distinct proteins. By comparing the sequence of 32-kDa calcimedin with the predicted sequence of endonexin II, we concluded that the primary structure of the 32-kDa protein is highly conserved. In particular, the sequences AMKGMGTDDEXEIXL, GMGTDEEEIL, VLTEILASR, and ILTSR conform to the endonexin consensus sequence, which is characteristic of the calpactin/lipocortin family.
Kobayashi
R
R
Department of Biochemistry, Akita University School of Medicine, Japan.
Hidaka
H
H
Tashima
Y
Y
D000199:Actins / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D017302:Annexins; D000906:Antibodies; D015153:Blotting, Western; D002135:Calcium-Binding Proteins / Q000302:isolation & purification* / Q000378:metabolism; D002645:Chickens; D002848:Chromatography, DEAE-Cellulose; D002850:Chromatography, Gel; D003429:Cross Reactions; D005895:Gizzard, Avian / Q000378:metabolism; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009130:Muscle, Smooth / Q000378:metabolism*; D010741:Phospholipases A / Q000037:antagonists & inhibitors; D054467:Phospholipases A2; D012689:Sequence Homology, Nucleic Acid
D000199:Actins; D017302:Annexins; D000906:Antibodies; D002135:Calcium-Binding Proteins; D010741:Phospholipases A; D054467:Phospholipases A2