• YAKHAK HOEJI
• /
• v.36 no.5
• /
• pp.460-468
• /
• 1992

Several bichemical parameters related to free radicals were estimated in senile-prone (P) and resistant(R) strains of male senescence-accelerated mice(SAM) at 2, 5 and 11 months of age. The superoxide generation was increased with age in SAM-R/1 and SAM-P/2. Compared to SAM-R/1, more generation of superoxide was significantly noted in the SAM-P/2 liver. The activities of Cu/Zn-superoxide dismutase and catalase were decreased during aging and these activities in SAM-P/2 were significantly lower than in SAM-R/l liver. The activities of glutathione S-transferase were varied with aging, whereas SAM-P/2 showed lower levels compared to SAM-R/l. The gradual decreases of glutathione, protein bound-SH and nonprotein bound-SH contents were noted with increasing age. SAM-P/2 liver contained lesser amounts of glutathione and nonprotein bound-SH compared to SAM-R. In conclusion, superoxide generation was increased whereas the antioxidant enzyme activities were decreased during aging in SAM-R/1. In addition, SAM-P/2 strain showed more superoxide generation and less antioxidant enzyme activities than SAM-R/1 in the liver, thus we assume that these factors might accelerate the senescence of SAM-P/2 strain.

• YAKHAK HOEJI
• /
• v.39 no.5
• /
• pp.528-534
• /
• 1995

This investigation was aimed at the study of the antidiabetic activity and effect on hepatic glutathione metabolism of polysaccharide from Trichosanthes kirilowii in hyperglycemic rats with aboxan (175 mg/Kg, i.p.). As the results, the polysaccharide inhibited the increase of blood glucose, triglyceride level and lactate dehydrogenase activity, but cholesterol not changed. And it increased protein bound-SH, nonprotein bound-SH, glutathione level and inhibited the decrease of glutathione S-transferase.

• BMB Reports
• /
• v.34 no.6
• /
• pp.537-543
• /
• 2001

In the present study, an in vitro ELISA system to assess the interaction between Src homology (SH)2 domains and phosphotyrosine that contain peptides was established using purified GST-conjugated SH2 proteins and synthetic biotinylated phosphotyrosine that contain oligopeptides. The SH2 domains bound the relevant phosphopeptides that were immobilized in the streptavidin-coated microtiter plate in a highly specific and dose-dependent manner. The epidermal growth factor receptor (EGFR)-, T antigen (T Ag)-, and platelet-derived growth factor receptor (PDGFR)-derived phosphopeptides interacted with the growth factor receptor binding protein (Grb)2/SH2, Lck/SH2, and phosphatidyl inositol 3-kinase (PI3K) p85/SH2, respectively. No cross-reactions were observed. Competitive inhibition experiments showed that a short phosphopeptide of only four amino acids was long enough to determine the binding specificity. Optimal concentrations of the GST-SH2 fusion protein and phosphopeptide in this new ELISA system for screening the binding blockers were chosen at 2nM and 500nM, respectively. When two candidate compounds were tested in our ELISA system, they specifically inhibited the Lck/SH2 and/or p85/SH2 binding to the relevant phosphopeptides. Our results indicate that this ELISA system could be used as an easy screening method for the discovery of specific binding blockers of protein-protein interactions via SH2 domains.

• The Korean Journal of Food And Nutrition
• /
• v.7 no.3
• /
• pp.232-238
• /
• 1994

Adriamycin is a major cancer chemotherapeutic agent against a me range of human neoplasms. However, its clinical application is limited since It has a variety of side effects, bone marrow suppression and cardiotoxity, and this toxicity appears by free radical. This study investigated the effect of Ampelopsis radix on the toxicity of adriamycin. The methanol fraction reduced slightly adriamycin induced lipid peroxidation and superoxide production at the dose of 50mg /kg. 1.p., respectively. During the adriamycin administration. Protein bound-SH, nonprotein bound-SH, and glutathione-5-transferase did not change, but methanol fraction treated group were markedly increase. These results indicated that Ampelopsis radix has a major influence on the thiol group and related enzyme activity on the antioxidative effects.

• Korean Journal of Pharmacognosy
• /
• v.25 no.2
• /
• pp.140-143
• /
• 1994

During the serial attempts to identify the chemical and biological characteristics of Ailanthi Cortex Radicis, the root bark of Ailanthus altissima (Simaroubaceae), we find out the serious toxic effect on kidney by chloroform fraction of the methanolic extract of the herb drug. The toxicities were revealed as the increase of urea nitrogen amount in blood and lactate dehydrogenase and ${\gamma}-glutamyltransferase$ activities in urine and the decrease of the concentration of glutathione and both of protein bound and non-protein bound -SH in kidney tissue.

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 1995.04a
• /
• pp.81-81
• /
• 1995

It is well known that Src Homology 2(SH2) domain in many intracellular signal transduction proteins is very important. The domain has about 100 amino acid residues and bind phosphotyrosine-containing peptide with high affinity and specificity. Lck SH2 domain is a Src-like, lymphocyte-specific tyrosine kinase. An 11-residue phosphopeptide derived from the hamster polvoma middle-T antigen, EPQp YEEIPIYL, binds with an 1 nM dissociation constant to Lck SH2 domain. And it is known that the phosphotyrosine and isoleucine residues of the peptide are tightly bound by two well-defined pockets on Lck SH2 domain's surface. To investigate the conformational changes during complexation of SH2 domain with phosphopeptide we have performed the molecular dynamics simulation for Lck SH2 domain with peptide and peptide-free form at look in aqueous solution. More than 3000 water molecules were incorporated to solvate Lck SH2 domain and peptide. Periodic boundary condition has been applied in molecular dynamics simulation. Data analysis with the results of that simulation shows that the phosphopeptide makes primary interaction with the Lck SH2 domain at six central residues, The comparison of the complexed and uncomplexed SH2 domain structures in solution has revealed only relatively small change. But the hydrophilic and hydrophobic pockets in the protein surface show the conformational changes in spite of the small structural difference between the complex and peptide-free forms.

• Journal of Haehwa Medicine
• /
• v.8 no.1
• /
• pp.659-674
• /
• 1999

The experimental studies were carried out in order to prove the effect of BSH water extract on Renal lipid peroxide content and metabolic enzyme system experimental studies about peroxide content, transferase, enzyme activity were carried out. The result were obtained as follows : 1. In the change of lipid peroxide of renal tissue, all group was decreased, more of two weeks was decreased. 2. In the Change of BUN of renal tissue, all group was decreased. 3. In the change of LDH of urine, all group was not significant. 4. In the change of ${\gamma}$-glutamyltransferasde, Xanthine oxidase, Aldehyde oxidase of urine, all group was decreased. 5. In the change of protein-bound SH, nonprotein-bound SH, glutathione, glutathione S-transferase, ${\gamma}$-Glutamylcystein synthetase of renal tissue, all group was increased. From above results, BSH was had significant effects on the senile, so it is expected to clinical application on senility and geratology.

• BMB Reports
• /
• v.37 no.5
• /
• pp.515-521
• /
• 2004

The tricarboxylate (or citrate) carrier was purified from eel liver mitochondria and functionally reconstituted into liposomes. Incubation of the proteoliposomes with various sulfhydryl reagents led to inhibition of the reconstituted citrate transport activity. Preincubation of the proteoliposomes with reversible SH reagents, such as mercurials and methanethiosulfonates, protected the eel liver tricarboxylate carrier against inactivation by the irreversible reagent N-(1-pyrenyl)maleimide (PM). Citrate and L-malate, two substrates of the tricarboxylate carrier, protected the protein against inactivation by sulfhydryl reagents and decreased the fluorescent PM bound to the purified protein. These results suggest that the eel liver tricarboxylate carrier requires a single population of free cysteine(s) in order to manifest catalytic activity. The reactive cysteine(s) is most probably located at or near the substrate binding site of the carrier protein.

• IMMUNE NETWORK
• /
• v.6 no.2
• /
• pp.67-75
• /
• 2006

Background: Cytotoxic function of killer cells is inhibited by specific recognition of class I MHC molecules on target cells by inhibitory killer Ig-like receptors (KIR) expressed on NK cells and some cytotoxic T cells. The inhibitory effect of KIR is accomplished by recruitment of SH2-containing protein tyrosine phosphatase (SHP) to the phosphotyrosine residues in the cytoplasmic tail. Methods: By in vitro coprecipitation experiments and transfection analysis, we investigated the association of KIR with an adaptor protein Shc in Jurkat T cells. Results: The cytoplasmic tail of KIR appeared to associate with an adaptor protein Shc in Jurkat T celilysates. Similar in vitro experiments showed that phosphorylated KIR cytoplasmic tail bound SHP-1 and Shc in Jurkat T cell lysates. The association of KIR with Shc was further confirmed by transfection analysis in 293T cells. Interestingly, however, Shc appeared to be replaced by SHP-2 upon engagement of KIR in 293T cells. Conclusion: Our data indicate that KIR associate with an adaptor protein Shc in Jurkat T cells, and suggest that KIR might have an additional role which is mediated by this adaptor protein.

• Journal of Life Science
• /
• v.27 no.10
• /
• pp.1191-1198
• /
• 2017

Vesicles and organelles are transported along microtubule and delivered to appropriate compartments in cells. The intracellular transport process is mediated by molecular motor proteins, kinesin, and dynein. Kinesin is a plus-end-directed molecular motor protein that moves the various cargoes along microtubule tracks. Kinesin 1 is first isolated from squid axoplasm is a dimer of two heavy chains (KHCs, also called KIF5s), each of which is associated with the light chain (KLC). KIF5s interact with many different binding proteins through their carboxyl (C)-terminal tail region, but their binding proteins have yet to be specified. To identify the interacting proteins for KIF5A, we performed the yeast two-hybrid screening and found a specific interaction with Ras-GTPase-activating protein (GAP) Src homology3 (SH3)-domain-binding protein 2 (G3BP2), which is involved in stress granule formation and mRNA-protein (mRNP) localization. G3BP2 bound to the C-terminal 73 amino acids of KIF5A but did not interact with the KIF5B, nor the KIF5C in the yeast two-hybrid assay. The arginine-glycine-glycine (RGG)/Gly-rich region domain of G3BP2 is a minimal binding domain for interaction with KIF5A. However, G3BP1 did not interact with KIF5A. When co-expressed in HEK-293T cells, G3BP2 co-localized with KIF5A and was co-immunoprecipitated with KIF5A. These results indicate that G3BP2, which was originally identified as a Ras-GAP SH3 domain-binding protein, is a protein that interacts with KIF5A.