Human liver calreticulin: characterization and Zn(2+)-dependent interaction with phenyl-sepharose.
A 60-kDa human calreticulin was isolated from liver homogenates. The protein was identified as calreticulin by its NH2-terminal amino acid sequence, by its mobility in SDS-PAGE, by its immunoreactivity with anti-calreticulin antibodies, by its Ca2+ binding, and by its localization to isolated ER membranes. In this study we show that Ca2+ binding to calreticulin results in Ca(2+)-dependent aggregation and precipitation of the protein. We also show that calreticulin and calsequestrin bind Zn2+ in 65Zn2+ overlay. In addition we have discovered that calreticulin exhibits a Zn(2+)-dependent interaction with hydrophobic matrix of phenyl-Sepharose that can be utilized in the purification of the protein.
Department of Gastroenterology, University of Freiburg, School of Medicine, Germany.
C
C
Heilmann
C
C
Spamer
E
E
Leberer
W
W
Gerok
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M
Michalak
D000818:Animals; D002135:Calcium-Binding Proteins / Q000302:isolation & purification / Q000378:metabolism*; D037282:Calreticulin; D002846:Chromatography, Affinity; D002848:Chromatography, DEAE-Cellulose; D004285:Dogs; D004591:Electrophoresis, Polyacrylamide Gel; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D006801:Humans; D008099:Liver / Q000378:metabolism*; D008970:Molecular Weight; D009132:Muscles / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism; D011485:Protein Binding; D051381:Rats; D012261:Ribonucleoproteins / Q000302:isolation & purification / Q000378:metabolism*; D012519:Sarcoplasmic Reticulum / Q000378:metabolism; D012685:Sepharose / Q000031:analogs & derivatives; D015032:Zinc / Q000378:metabolism* / Q000494:pharmacology
D002135:Calcium-Binding Proteins; D037282:Calreticulin; D012261:Ribonucleoproteins; C020927:phenyl-sepharose; D012685:Sepharose; D015032:Zinc