• 제목/요약/키워드: Protein complex

검색결과 1,474건 처리시간 0.032초

Regulation of Macrophage Ceruloplasmin Gene Expression: One Paradigm of 3'-UTR-mediated Translational Control

  • Mazumder, Barsanjit;Sampath, Prabha;Fox, Paul L.
    • Molecules and Cells
    • /
    • 제20권2호
    • /
    • pp.167-172
    • /
    • 2005
  • Ceruloplasmin (Cp) is a copper protein with important functions in iron homeostasis and in inflammation. Cp mRNA expression is induced by interferon (IFN)-${\gamma}$ in U937 monocytic cells, but synthesis of Cp protein is halted after about 12 h by transcript-specific translational silencing. The silencing mechanism requires binding of a 4-component cytosolic inhibitor complex, IFN-gamma-activated inhibitor of translation (GAIT), to a defined structural element (GAIT element) in the Cp 3'-UTR. Translational silencing of Cp mRNA requires the essential proteins of mRNA circularization, suggesting that the translational inhibition requires end-to-end mRNA closure. These studies describe a new mechanism of translational control, and may shed light on the role that macrophage-derived Cp plays at the intersection of iron homeostasis and inflammation.

Chlorella 세포의 핵산 인단백질 및 인지질의 생합성에 미치는 마그네슘의 결핍 효과 (Effect of magnesium-deficiency on the biosynthesis of nucleic acid, phosphoprotein, and phospholipid in Chlorella cells)

  • 이영록
    • Journal of Plant Biology
    • /
    • 제11권1호
    • /
    • pp.15-21
    • /
    • 1968
  • Chlorella ellipsoidea were grown in a Mg-free medium. Aliquots of the algal cell were taken out at the beginning and predetermined time intervals during the culture and were analyzed the contents of phosphate in various fractions of the cell constituents. The results obtained were compared with those of the control. When Chlorella cells were grown in a Mg-free medium, the contents of phosphate in the DNA protein, RNA-olyphosphate complex, nucleotidic-lbileP, and PCA-soluble, fractions decreased compared with those of the control, while the content of acid insoluble polyphosphate increased significantly. On the otherhand, RNA-P and lipid-P showed the tendency of decrease at the early stage of the culture, but they were increased more than those in the control as culture proceeds. It is showed that phosphate turnover from acid-insoluble polyphosphate into DNA, protein, and RNA-polyphosphate complex was inhibited by magnesium-deficiency of the cells.

  • PDF

약물의 간내 이행기전과 알부민의 역할 (Albumin-Mediated Hepatic Uptake of Drugs)

  • 한용해;심창구
    • Journal of Pharmaceutical Investigation
    • /
    • 제20권4호
    • /
    • pp.179-191
    • /
    • 1990
  • A central dogma of pharmacology is that only unbound drug is capable of translocation across biological membrane. Thus, hepatic uptake is assumed to be solely determined by the unbound concentration of the diffusible moiety at the surface of the liver cell. However, an increasing number of experimental observations with xenobiotics that are normally very extensively bound to plasma proteins (>99%) appear to be inconsistent with these assumptions. This suggested that in addition to progressive spontaneous dissociation within the liver sinusoids and space of Disse, direct interactions of the albumin-drug complex at the plasma membrane may facilitate dissociation of the complex. To explain this phenomena. called albumin-mediated uptake, 4 mechanisms have been suggested. The validity of such hypotheses needs to be examined by the further study. Because albumin-mediated uptake has also been observed to occur in other plasma proteins, protein-mediated uptake rather than albumin-mediated uptake seems to be acceptable.

  • PDF

Environmentally benign. Background-free protein staining in SDS-polyacrylamide gels using an counter ion-dye complex solution.

  • Jin , Li-Tai;Hwang, Sun-Young;Yoo, Gyurng-Soo;Choi, Jung-Kap
    • 대한약학회:학술대회논문집
    • /
    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
    • /
    • pp.313.2-313.2
    • /
    • 2002
  • Environmentally benign protein staining method in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) using both an acidic dye, zincon (ZC) and a basic dye. ethyl violet (EV) is described. It is based on a counter ion-dye staining technique that employs oppositely charged two dyes to form an ion-pair complex. The selective binding of the free dye molecules to proteins in an acidic solution produces bluish violet colored bands. It is a rapid procedure, involving only fixin and staining steps that are completed in 45 min. (omitted)

  • PDF

α-Kleisin subunit of cohesin preserves the genome integrity of embryonic stem cells

  • Seobin Yoon;Eui-Hwan Choi;Seo Jung Park;Keun Pil Kim
    • BMB Reports
    • /
    • 제56권2호
    • /
    • pp.108-113
    • /
    • 2023
  • Cohesin is a ring-shaped protein complex that comprises the SMC1, SMC3, and α-kleisin proteins, STAG1/2/3 subunits, and auxiliary factors. Cohesin participates in chromatin remodeling, chromosome segregation, DNA replication, and gene expression regulation during the cell cycle. Mitosis-specific α-kleisin factor RAD21 and meiosis-specific α-kleisin factor REC8 are expressed in embryonic stem cells (ESCs) to maintain pluripotency. Here, we demonstrated that RAD21 and REC8 were involved in maintaining genomic stability and modulating chromatin modification in murine ESCs. When the kleisin subunits were depleted, DNA repair genes were downregulated, thereby reducing cell viability and causing replication protein A (RPA) accumulation. This finding suggested that the repair of exposed single-stranded DNA was inefficient. Furthermore, the depletion of kleisin subunits induced DNA hypermethylation by upregulating DNA methylation proteins. Thus, we proposed that the cohesin complex plays two distinct roles in chromatin remodeling and genomic integrity to ensure the maintenance of pluripotency in ESCs.

Evidence of complex formation between FADD and c-FLIP death effector domains for the death inducing signaling complex

  • Hwang, Eun Young;Jeong, Mi Suk;Park, So Young;Jang, Se Bok
    • BMB Reports
    • /
    • 제47권9호
    • /
    • pp.488-493
    • /
    • 2014
  • Adaptor protein FADD forms the death inducing signaling complex (DISC) by recruiting the initiating caspases-8 and -10 through homotypic death effector domain (DED) interactions. Cellular FLICE-inhibitory protein (c-FLIP) is an inhibitor of death ligand-induced apoptosis downstream of death receptors, and FADD competes with procaspase-8/10 for recruitment for DISC. However, the mechanism of action of FADD and c-FLIP proteins remain poorly understood at the molecular level. In this study, we provide evidence indicating that the death effector domain (DED) of FADD interacts directly with the death effector domain of human c-FLIP. In addition, we use homology modeling to develop a molecular docking model of FADD and c-FLIP proteins. We also find that four structure-based mutants (E80A, L84A, K169A and Y171A) of c-FLIP DEDs disturb the interaction with FADD DED, and that these mutations lower the stability of the c-FLIP DED.

백굴채ㆍ목과ㆍ위영선 혼합 약침액이 관절염 백선의 염증과 간에 미치는 영향 (Effects of Herba ChelidoniiㆍClematis Florida ThunbㆍChaenomelis Fructus Complex Herbal Acupuncture on Anti-Inflamation and Liver in Rats with Arthritis induced Freund's Complete Adjuvant)

  • 장승욱;김연섭
    • 동의생리병리학회지
    • /
    • 제18권2호
    • /
    • pp.484-489
    • /
    • 2004
  • Objective : In order to study the effects of Herba ChelidoniiㆍClematis Florida ThunbㆍChaenomelis Fructus complex herbal acupuncture on anti-inflammation and liver in rats with arthritis induced Freund's complete adjuvant. Method : We performed several experimental items : that is edema value, numbers of WBC. total protein, total bilirrubin, SGOT, SGPT. Result: The change in the right plantar edema shows that Control group was reduced by 0% but, ST group ,Sample A group and Sample B group were reduced by 287.2%, 343.0%, 272.5% respectively. In the WBC count, ST group, Sample A group, Sample B group showed a decrease with statistical significance as compared with control group. In the total protein, Sample B group showed a decrease with statistical significance as compared with control group. In the total bilirrubin, SGOT, SGPT, None showed noxious variation with statistical significance as compared with control group. Conclusion : As a result of this experiment, it is concluded that Herba ChelidoniiㆍClematis Florida ThunbㆍChaenomelis Fructus complex herbal acupuncture showed that therapeutic effect of anti-inflammation in adjuvant arthritis and non-toxic effect of liver.

Bacterial Overexpression and Denaturing Purification of VPS34-Binding Domain of Beclin 1

  • Baek, Jong-Hyuk;Jung, Juneyoung;Seo, Jeongbin;Kim, Jeong Hee;Kim, Joungmok
    • Journal of Microbiology and Biotechnology
    • /
    • 제26권10호
    • /
    • pp.1808-1816
    • /
    • 2016
  • As a scaffolding subunit of the PIK3C3/VPS34 complex, Beclin 1 recruits a variety of proteins to class III phosphatidylinositol-3-kinase (VPS34), resulting in the formation of a distinct PIK3C3/VPS34 complex with a specific function. Therefore, the investigation of a number of Beclin 1 domains required for the protein-protein interactions will provide important clues to understand the PIK3C3/VPS34 complex, of which Beclin1-VPS34 interaction is the core unit. In the present study, we have designed a bacterial overexpression system for the Beclin 1 domain corresponding to VPS34 binding (Vps34-BD) and set up the denaturing purification protocol due to the massive aggregation of Vps34-BD in Escherichia coli. The expression and purification conditions determined in this study successfully provided soluble and functional Vps34-BD.

산약(山藥) 점액성분(粘液成分)의 정제(精製)와 함량분석(含量分析)에 관한 연구(硏究) (Purification of Mucilages from Dioscorea batatas and D.japonica and their Content Analysis)

  • 한용남;한승혜;이인란
    • 생약학회지
    • /
    • 제21권4호
    • /
    • pp.274-283
    • /
    • 1990
  • This study was conducted to further characterize mucilages from Dioscoreae Rhizoma, which have been known to be proteoglycans. We chose the two types of yams, Dioscorea batatas Dec. (club-like) and D. japonica Thunb. (cane-like). Repeated gel filtration of a dialyzed water extract of each fresh yam on Bio-gel P-100 and then Sephadex G-150 columns completely separated the mucilage from protein. Furthermore, gel filtration of a water extract from each yam processed by steaming and drying on the Bio-gel P-100 column gave only one polysaccharide peak without protein. These results revealed that the mucilages of yams were only composed of polysaccharide. Then we assessed some properties of the mucilages under three kinds of criteria: a complex-forming capacity between mucilage and alcian blue, mannose content in the mucilage, and viscosity. The complex-forming capacities of two types of fresh yams were closely similar with each other, but the processing of two types of the fresh yams greatly lowered the complex-forming capacity and viscosity.

  • PDF

Protein-protein interaction between caveolin-1 and SHP-2 is dependent on the N-SH2 domain of SHP-2

  • Park, Hyunju;Ahn, Keun Jae;Kang, Jihee Lee;Choi, Youn-Hee
    • BMB Reports
    • /
    • 제48권3호
    • /
    • pp.184-189
    • /
    • 2015
  • Src homology 2-containing protein tyrosine phosphatase 2 (SHP-2) is known to protect neurons from neurodegeneration during ischemia/reperfusion injury. We recently reported that ROS-mediated oxidative stress promotes phosphorylation of endogenous SHP-2 in astrocytes and complex formation between caveolin-1 and SHP-2 in response to oxidative stress. To examine the region of SHP-2 participating in complex formation with caveolin-1, we generated three deletion mutant constructs and six point mutation constructs of SHP-2. Compared with wild-type SHP-2, binding of the N-SH2 domain deletion mutant of SHP-2 to p-caveolin-1 was reduced greatly, using flow cytometric competitive binding assays and surface plasmon resonance (SPR). Moreover, deletion of the N-SH2 domain of SHP-2 affected $H_2O_2$-mediated ERK phosphorylation and Src phosphorylation at Tyr 419 in primary astrocytes, suggesting that N-SH2 domain of SHP-2 is responsible for the binding of caveolin-1 and contributes to the regulation of Src phosphorylation and activation following ROS-induced oxidative stress in brain astrocytes.