Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of regucalcin, a calcium-binding protein, on neutral proteolytic activity in the cytosol of rat kidney cortex was investigated. Proteolytic activity was significantly increased in the presence of regucalcin (0.01-0.25 microM) in the enzyme reaction mixture. This increase was not significantly altered by the addition of CaCl, (0.01 and 1.0 mM) or EGTA (1.0 mM), indicating that the effect of regucalcin was independent on Ca2+. The effect of regucalcin to increase proteolytic activity was completely prevented in the presence of N-ethylmaleimide (5 mM), a modifying reagent of thiol groups. Proteolytic activity was clearly elevated by dithiothreitol (5 mM). This elevation was further enhanced by regucalcin (0.1 microM). Meanwhile, the stimulatory effect of regucalcin on proteolytic activity was not significantly altered in the presence of diisopropylfluorophosphate (2.5 mM), an inhibitor of serine proteases. Also, the regucalcin effect was not appreciably changed by the addition of EDTA (2.5 mM), a chelator of metal ions, indicating that it is not involved in metal-related proteases. These results demonstrate that regucalcin can increase proteolytic activity in the cytosol of rat kidney cortex. Regucalcin may activate thiol proteases independent on Ca2+.
Mol Cell Biochem 1999 May
PMID:Stimulatory effect of regucalcin on proteolytic activity in rat renal cortex cytosol: involvement of thiol proteases. 1039 72

The effect of anti-regucalcin monoclonal antibody on neutral phoshatase activity in rat liver cytosol was investigated. Phosphotyrosine, phosphoserine, and phosphothreonine were used as the substrate toward phosphatase assay. Liver cytosolic phosphatase activity with three phosphoaminoacids was significantly increased in the presence of anti-regucalcin antibody (100 and 200 ng/ml) in the enzyme reaction mixture with calcium chloride (0.1 mM) or EGTA (1.0 mM). The effect of anti-regucalcin antibody was completely abolished in the presence of exogenous regucalcin (1.0 microM), indicating the involvement of endogenous regucalcin. The anti-regucalcin anti body- increased phosphatase activity was not significantly altered in the presence of trifluoperazine (20 microM), an antagonist of calmodulin, or akadaic acid ( 10 microM), an inhibitor of protein phosphatase, although these inhibitors caused a slight decrease in liver cytosolic phosphatase activity. The effect of endogenous regucalcin might be not related to calmodulin, and it was insensitive to okadaic acid. The present findings suggest that endogenous regucalcin is involved in the regulation of protein phasphatase in rat liver cytoplasm.
Mol Cell Biochem 1999 Jul
PMID:Effect of anti-regucalcin antibody on neutral phosphatase activity in rat liver cytosol: involvement of endogenous regucalcin. 1048 20

Rsp5 is an E3 ubiquitin-protein ligase of Saccharomyces cerevisiae that belongs to the hect domain family of E3 proteins. We have previously shown that Rsp5 binds and ubiquitinates the largest subunit of RNA polymerase II, Rpb1, in vitro. We show here that Rpb1 ubiquitination and degradation are induced in vivo by UV irradiation and by the UV-mimetic compound 4-nitroquinoline-1-oxide (4-NQO) and that a functional RSP5 gene product is required for this effect. The 26S proteasome is also required; a mutation of SEN3/RPN2 (sen3-1), which encodes an essential regulatory subunit of the 26S proteasome, partially blocks 4-NQO-induced degradation of Rpb1. These results suggest that Rsp5-mediated ubiquitination and degradation of Rpb1 are components of the response to DNA damage. A human WW domain-containing hect (WW-hect) E3 protein closely related to Rsp5, Rpf1/hNedd4, also binds and ubiquitinates both yeast and human Rpb1 in vitro, suggesting that Rpf1 and/or another WW-hect E3 protein mediates UV-induced degradation of the large subunit of polymerase II in human cells.
Mol Cell Biol 1999 Oct
PMID:Rsp5 ubiquitin-protein ligase mediates DNA damage-induced degradation of the large subunit of RNA polymerase II in Saccharomyces cerevisiae. 1049 Jun 34

The expression of hepatic Ca2+-binding protein regucalcin in the cloned rat hepatoma cells (H4-II-E) was investigated. The change in regucalcin mRNA levels was analyzed by Northern blotting using rat liver regucalcin complementary DNA (0.9 kb of open reading frame). Regucalcin mRNA was expressed in H4-II-E hepatoma cells. This expression was clearly stimulated in the presence of serum (10% fetal bovine serum). Bay K 8644 (2. 5 x 10(-6) M), a Ca2+ channel agonist, significantly stimulated regucalcin mRNA expression in the absence or presence of 10% serum. Dibutyryl cyclic AMP (10(-3) M) did not have a stimulatory effect on the regucalcin mRNA expression. The presence of phorbol 12-myristate 13-acetate (PMA; 10(-6) M) or estrogen (10(-8) M) caused a significant increase in regucalcin mRNA levels in the hepatoma cells cultured in serum-free medium, while insulin (5 x 10(-9) M) or dexamethasone (10(-6) M) had no effect. Bay K 8644-stimulated regucalcin mRNA expression in the hepatoma cells was completely blocked in the presence of trifluoperazine (10(-5) M), an antagonist of calmodulin, or staurosporine (10(-7) M), an inhibitor of protein kinase C. The stimulatory effect of PMA was clearly inhibited in the presence of stauroporine. The present study demonstrates that regucalcin mRNA is expressed in the transformed H4-II-E hepatoma cells, and that the expression is stimulated through Ca2+-dependent signaling factors.
Mol Cell Biochem 1999 Aug
PMID:Expression of calcium-binding protein regucalcin mRNA in the cloned rat hepatoma cells (H4-II-E) is stimulated through Ca2+ signaling factors: involvement of protein kinase C. 1049 83

Ca2+-binding protein regucalcin is expressed in the kidney cortex of rats, as assayed by Northern blot analysis. The existence of kidney nuclear factor which binds to the 5'-flanking region of the rat regucalcin gene was investigated. When nuclear extracts obtained from the kidney cortex of rats were used in gel mobility-shift assays, two protein-DNA complexes were uniquely formed with the DNA fragment containing the 5'-flanking region of the rat regucalcin gene. Competition gel shift experiments indicated the specific binding region of kidney cortex nuclear proteins in the 5'-flanking region of the rat regucalcin gene. The two nuclear protein-DNA complexes were formed with the same mobility in rat kidney cortex and liver, which possess detectable amounts of regucalcin mRNA in Northern blot analysis. The binding activities of nuclear factors from kidney cortex to the 5'-flanking region of the rat regucalcin gene were inhibited by a single intraperitoneal administration of trifluoperazine, an antagonist of calmodulin, to rats. The present study demonstrates that kidney cortex nuclear proteins specifically bind to the 5'-flanking region of the rat regucalcin gene, and that the binding activity may be partly mediated through the Ca2+/calmodulin-dependent process.
Mol Cell Biochem 1999 Sep
PMID:Binding of kidney nuclear proteins to the 5'-flanking region of the rat gene for Ca2+-binding protein regucalcin: involvement of Ca2+/calmodulin signaling. 1054 49

The expression of calcium-binding protein regucalcin and its effect on the microsomal Ca2+-ATPase activity in rat brain tissues was investigated. The expression of regucalcin mRNA was demonstrated by reverse transcription-polymerase chain reaction (RT-PCR) analysis in brain tissues using rat regucalcin-specific primers. Regucalcin concentration in the brain tissues was about 5 x 10(-9)) M as measured using enzyme-linked immunoadsorbent assay (ELISA), and this level was lowered with increasing age (50 weeks old). The presence of regucalcin (10(-9) to 10(-7) M) in the enzyme reaction mixture caused a significant decrease in Ca2+-ATPase activity in the brain microsomes of young rats (5 weeks old). Meanwhile, the enzyme activity was not significantly altered by the addition of calmodulin (1 or 50 microg/ml), calbindin (1 or 10 microg/ml), and S-100 A protein (5 or 25 microg/ml), which are other Ca2+-binding proteins in rat brain. The effect of regucalcin to inhibit microsomal Ca2+-ATPase activity was weakened in the brain of rats with increasing age (50 weeks old). The present study demonstrates that regucalcin is expressed in the brain, and that it can uniquely inhibit Ca2+-ATPase activity in the brain microsomes of rats. The findings suggest that regucalcin plays a role in the regulation of microsomal Ca2+-ATPase activity in rat brain tissues.
Mol Cell Biochem 1999 Oct
PMID:Expression of calcium-binding protein regucalcin and microsomal Ca2+-ATPase regulation in rat brain: attenuation with increasing age. 1056 82

Regucalcin is a Ca2+-binding protein which plays a regulatory role in liver cell functions related to Ca2+. In this study we have cloned and characterized cDNA for regucalcin from human liver and human hepatoma cell line Hep G2 by screening and rapid amplification of cDNA ends (RACE). The nucleotide sequences of the clones revealed that they were identical in their coding region and differed only in their 5' untranslated regions (UTRs). Northern blot analysis showed that regucalcin mRNA in the Hep G2 was longer than that of the liver. The present study demonstrates the existence of transcript heterogeneity of the human gene for regucalcin.
Int J Mol Med 2000 Mar
PMID:Transcript heterogeneity of the human gene for Ca2+-binding protein regucalcin. 1067 70

The effect of regucalcin (RC) on neutral proteolytic activity in the cytosol of rat kidney cortex was investigated. Proteolytic activity was significantly increased by the presence of RC (0.01-0.10 microM) in the enzyme reaction mixture. This increase was completely abolished by the addition of anti-RC monoclonal antibody (150 ng/ml). When the renal cortex cytosol was incubated without RC addition, the degradation of globin of substrate was demonstrated by sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis. This degradation was clearly inhibited by the addition of anti-RC antibody (150 ng/ml), indicating that protein degradation results partly from the cytosolic endogenous RC. Meanwhile, proteolytic activity was significantly decreased in the renal cortex cytosol of rats with saline ingestion for 2, 7, and 14 days. The effect of RC (0.1 microM) in increasing proteolytic activity was weakened in the kidney cortex cytosol of saline-ingested rats. The present study suggests that endogenous RC plays a role in the activation of proteases in the renal cortex cytosol, and that the RC effect is impaired in saline-ingested rats.
Mol Cell Biochem 2000 Mar
PMID:Stimulatory effect of regucalcin on proteolytic activity is impaired in the kidney cortex cytosol of rats with saline ingestion. 1083 88

Regucalcin is a Ca2+-binding protein, which plays a regulatory role in liver cell functions related to Ca2+. In this study we have cloned cDNA for regucalcin from rabbit, bovine, chicken and toad livers by using rapid amplification of cDNA ends (RACE) method. The nucleotide and amino acid sequences of them are compared with published human, rat and mouse sequences. Comparison analysis revealed that the nucleotide sequences of regucalcin from seven vertebrate species were highly conserved in their coding region. The overall regucalcin proteins in these species consisted of 299 amino acids, and they had 69.9-91.3% identity. Furthermore, phylogenetic analysis showed that regucalcin in seven species appears to form a single cluster. This study demonstrates a great conservation of the regucalcin genes throughout evolution.
Int J Mol Med 2000 Aug
PMID:The gene of Ca2+-binding protein regucalcin is highly conserved in vertebrate species. 1089 65

The effect of regucalcin, which is a regulatory protein in Ca2+ signaling, on protein synthesis in regenerating rat liver was investigated. Protein synthesis was assayed in a reaction mixture containing the 5500 g supernatant fraction in the presence of [3H]leucine. The presence of anti-regucalcin monoclonal antibody (100 and 150 ng/ml) in the reaction mixture caused a significant elevation of in vitro protein synthesis. This elevation was completely prevented by the addition of regucalcin (1.0 microM). Regenerating liver after partial hepatectomy (HPX) induced a significant increase in protein synthesis. This increase was significantly enhanced by the presence of anti-regucalcin monoclonal antibody (100 ng/ ml). This enhancement was remarkable at 24 and 48 h after HPX. [3H]Leucyl-tRNA synthetase activity in the 105000 g supernatant fraction (cytosol) of the liver homogenate from normal rats was significantly raised by the presence of antibody (100 and 150 ng/ml) in the enzyme reaction mixture. Regenerating liver caused a significant elevation of the enzyme activity at 24, 48, and 72 h after HPX. This elevating was significantly enhanced in the presence of antibody (100 ng/ml). The present study suggests that endogenous regucalcin has a suppressive effect on the enhancement of protein synthesis in regenerating rat liver with a proliferative cells.
Int J Mol Med 2000 Sep
PMID:Suppressive effect of endogenous regucalcin on the enhancement of protein synthesis and aminoacyl-tRNA synthetase activity in regenerating rat liver. 1093 92


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