RGD Reference Report - Stimulatory effect of regucalcin on ATP-dependent Ca(2+) uptake activity in rat liver mitochondria. - Rat Genome Database

Send us a Message



Submit Data |  Help |  Video Tutorials |  News |  Publications |  Download |  REST API |  Citing RGD |  Contact   

Stimulatory effect of regucalcin on ATP-dependent Ca(2+) uptake activity in rat liver mitochondria.

Authors: Takahashi, H  Yamaguchi, M 
Citation: Takahashi H and Yamaguchi M, J Cell Biochem. 2000 Apr;78(1):121-30.
RGD ID: 9590178
Pubmed: (View Article at PubMed) PMID:10797571

The effect of Ca(2+)-binding protein regucalcin on Ca(2+)-ATPase activity in isolated rat liver mitochondria was investigated. The presence of regucalcin (0.1, 0.25, and 0.5 microM) in the enzyme reaction mixture led to a significant increase in Ca(2+)-ATPase activity. Regucalcin significantly stimulated ATP-dependent (45)Ca(2+) uptake by the mitochondria. Ruthenium red (10(-5) M) or lanthanum chloride (10(-4) M), an inhibitor of mitochondrial Ca(2+) uptake, completely inhibited regucalcin (0.25 microM)-increased mitochondrial Ca(2+)-ATPase activity and (45)Ca(2+) uptake. The effect of regucalcin (0.25 microM) in increasing Ca(2+)-ATPase activity was completely inhibited by the presence of digitonin (10(-2)%), a solubilizing reagent of membranous lipids, or vanadate (10(-5) M), an inhibitor of phosphorylation of ATPase. The activatory effect of regucalcin (0.25 microM) on Ca(2+)-ATPase activity was not further enhanced in the presence of dithiothreitol (2.5 mM), a protecting reagent of the sulfhydryl (SH) group of the enzyme, or calmodulin (0.60 microM), a modulator protein of Ca(2+) action that could increase mitochondrial Ca(2+)-ATPase activity. The present study demonstrates that regucalcin can stimulate Ca(2+) pump activity in rat liver mitochondria, and that the protein may act on an active site (SH group)-related to phosphorylation of mitochondrial Ca(2+)-ATPase.

Annotation

Gene Ontology Annotations    

Biological Process

Objects Annotated

Genes (Rattus norvegicus)
Rgn  (regucalcin)


Additional Information