• 제목/요약/키워드: Cellular proteins

검색결과 1,342건 처리시간 0.028초

ADP-Ribosylation: Activation, Recognition, and Removal

  • Li, Nan;Chen, Junjie
    • Molecules and Cells
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    • 제37권1호
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    • pp.9-16
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    • 2014
  • ADP-ribosylation is a type of posttranslational modification catalyzed by members of the poly(ADP-ribose) (PAR) polymerase superfamily. ADP-ribosylation is initiated by PARPs, recognized by PAR binding proteins, and removed by PARG and other ADP-ribose hydrolases. These three groups of proteins work together to regulate the cellular and molecular response of PAR signaling, which is critical for a wide range of cellular and physiological functions.

다양한 환경변이원의 분자독성학적 메커니즘 연구에 있어서 항종양 인자 p53의 중요성 고찰 (The Overview of the Importances of Tumor Suppressor p53 for Investigating Molecular Toxicological Mechanisms of Various Environmental Mutagens)

  • 정화진;류재천;서영록
    • Environmental Analysis Health and Toxicology
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    • 제19권3호
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    • pp.321-326
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    • 2004
  • The study of p53 tumor suppressor protein is one of most important subjects in an environmental toxicology as well as in cancer biology. Generally, p53 has been known to involve the cell cycle regulation and apoptosis by the activation of its target genes such as p21 and bax in a number of cellular stress responses. In addition, associations of p53 with cellular proteins presumably reflect the involvement of p53 in critical cellular processes such as DNA repair. The complex formation of p53 and exogenous proteins such as viral or cellular proteins has been shown in many cases to play important roles in carcinogenic processes against environmental mutagen. Recently, the disruption of p53 protein by oxidative stress has been also reported to have relevance to carcinogenesis. These findings suggested that the maintaining of stability and functional activity of p53 protein was also important aspect to play as a tumor suppressor protein. Therefore, the detection of functional status of p53 proteins might be an effective biomarker for the cancer and human diseases under the environmental toxicologic carcinogen.

Proteomic Analysis of Differentially Expressed Proteins in Human Lung Cells Following Formaldehyde Treatment

  • Jeon, Yu-Mi;Ryu, Jae-Chun;Lee, Mi-Young
    • Molecular & Cellular Toxicology
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    • 제3권4호
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    • pp.238-245
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    • 2007
  • Chronic formaldehyde inhalation studies have suggested its relativity to teratogenicity, cancer incidence, neurodegenerative and vascular disorders. Many toxicological data on the formaldehyde toxicity are available, but proteomic results showing complete protein profiles are limited. Therefore, alterations of protein expression patterns upon formaldehyde treatment were investigated in the human lung epithelial cell line. Differentially expressed proteins following formaldehyde treatment were analyzed on 2-dimensional gels, and further analyzed by MALDI-TOF to identify the proteins. Among the identified proteins, 24 proteins were notably up-regulated and 6 proteins were down-regulated. In particular, cytoskeleton related protein named vinculin and Rho GDP dissociation inhibitor which plays a key role in apoptosis increased remarkably.

Regulatory Viral and Cellular Elements Required for Potato Virus X Replication

  • Kim, Kook-Hyung
    • The Plant Pathology Journal
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    • 제17권3호
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    • pp.115-122
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    • 2001
  • Potato virus X (PVX) is a flexuous rod-shaped virus containing a single plus-strand RNA. Viral RNA synthesis is precisely regulated by regulatory viral sequences and by viral and/or host proteins. RNA sequence element as well as stable RNA stem-loop structure in the 5' end of the genome affect accumulation of genomic RNA and subgenomic RNA (sgRNA). The putative sgRNA promoter regions upstream of the PVX triple gene block (TB) and coat protein (CP) gene were critical for both TB and CP sgRNA accumulation. Mutations that disrupted complementarity between a region at the 5' end of the genomic RNA and the sequences located upstream of each sgRNA initiation site is important for PVX RNA accumulation. Compensatory mutations that restore complementarity restored sgRNA accumulation levels. However, the extent of reductions in RNA levels did not directly correlate with the degree of complementarity, suggesting that the sequences of these elements are also important. Gel-retardation assays showed that the 5' end of the positive-strand RNA formed an RNA-protein complex with cellular proteins, suggesting possible involvement of cellular proteins for PVX replication. Future studies on cellular protein binding to the PVX RNA and their role in virus replication will bring a fresh understanding of PVX RNA replication.

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Cell Behavior of Human Papillomavirus-immortalized and Tumorigenic Human Oral Keratinocytes Does Not Depend on the Integrin Expression

  • Park, Kyung-Hee;Min, Byung-Moo
    • International Journal of Oral Biology
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    • 제32권3호
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    • pp.93-101
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    • 2007
  • Cell behavior of the transformed cells is known to affect by interaction with extracellular matrix (ECM) proteins and integrin. To investigate the alterations of both integrin expression and cell-matrix interaction during neoplastic conversion of human oral kerationcytes, we studied expression levels of integrin subunits by flow cytometry and cellular responses to the ECM proteins in normal human oral keratinocytes (NHOKs), HPV-immortalized HOK-16B line, and three oral cancer cell lines established from HOK-16B line, CTHOK-16B-BaP, CTHOK-16B-DMBA, and CTHOK-16B-Dexa lines. The expression levels of ${\alpha}\;and\;{\beta}$ integrin subunits were shown decreased tendency in human oral keratinocytes undergoing immortalization and tumorigenic transformation except CTHOK-16B-DMBA line tested. Although ${\alpha}v{\beta}6$ integrin is known to be highly expressed in squamous cell carcinomas, and the altered integrin expression is suspected to be associated with cellular carcinogenesis, ${\alpha}v$ integrin subunit and ${\alpha}v{\beta}6$ integrin did not express in oral cancer cell lines tested. Cell behavior to the ECM proteins in HOK-16B line was generally similar to that of exponentially proliferating NHOKs. The adhesion activity profiles of type I collagen were very similar to that of its laminin counterparts, but fibronectin showed minimal adhesion activity under our conditions compared to the BSA control. The ability of the CTHOK-16B-BaP line to spread upon type I collagen and laminin markedly decreased, but migration was notably increased on type I collagen. In contrast, CTHOK-16B-DMBA and CTHOK-16B-Dexa lines spread less but migrated more upon type I collagen than immortalized HOK-16B line. These data indicate that downregulation of integrin subunits causes the changes of cellular responses to the ECM proteins during neoplastic conversion of human oral keratinocytes, and that cellular responses to the ECM proteins in oral cancer cell lines established by exposing different carcinogens are variable according to chemical carcinogens treatment.

Network-Based Protein Biomarker Discovery Platforms

  • Kim, Minhyung;Hwang, Daehee
    • Genomics & Informatics
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    • 제14권1호
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    • pp.2-11
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    • 2016
  • The advances in mass spectrometry-based proteomics technologies have enabled the generation of global proteome data from tissue or body fluid samples collected from a broad spectrum of human diseases. Comparative proteomic analysis of global proteome data identifies and prioritizes the proteins showing altered abundances, called differentially expressed proteins (DEPs), in disease samples, compared to control samples. Protein biomarker candidates that can serve as indicators of disease states are then selected as key molecules among these proteins. Recently, it has been addressed that cellular pathways can provide better indications of disease states than individual molecules and also network analysis of the DEPs enables effective identification of cellular pathways altered in disease conditions and key molecules representing the altered cellular pathways. Accordingly, a number of network-based approaches to identify disease-related pathways and representative molecules of such pathways have been developed. In this review, we summarize analytical platforms for network-based protein biomarker discovery and key components in the platforms.

Alterations of Protein Expression in Macrophages in Response to Candida albicans Infection

  • Shin, Yu-Kyong;Kim, Ki-Young;Paik, Young-Ki
    • Molecules and Cells
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    • 제20권2호
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    • pp.271-279
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    • 2005
  • Although macrophages are an important first line of cellular defense, they are unable to effectively kill phagocytosed C. albicans. To determine the physiological basis of this inability, we investigated the alterations of macrophage proteins caused by C. albicans infection. Since the formation of C. albicans hyphae caused cell death, proteins were prepared 3 h after infection and examined by two-dimensional gel electrophoresis (2-DE). The most prominent changes were in glycolytic enzymes, which could have caused energy depletion of the infected cells. Also changed were proteins involved in maintenance of cellular integrity and NO production. Treatment of the macrophages with either cytochalasin D or taxol did not alter their inability to kill C. albicans. Our results indicate that multiple factors contribute to cell death as the pathogenic form of C. albicans becomes fully active inside macrophage cells.

Enhanced delivery of protein fused to cell penetrating peptides to mammalian cells

  • Moon, Jung-Il;Han, Min-Joon;Yu, Shin-Hye;Lee, Eun-Hye;Kim, Sang-Mi;Han, Kyuboem;Park, Chang-Hwan;Kim, Chun-Hyung
    • BMB Reports
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    • 제52권5호
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    • pp.324-329
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    • 2019
  • Recent progress in cellular reprogramming technology and lineage-specific cell differentiation has provided great opportunities for translational research. Because virus-based gene delivery is not a practical reprogramming protocol, protein-based reprogramming has been receiving attention as a safe way to generate reprogrammed cells. However, the poor efficiency of the cellular uptake of reprogramming proteins is still a major obstacle. Here, we reported key factors which improve the cellular uptake of these proteins. Purified red fluorescent proteins fused with 9xLysine (dsRED-9K) as a cell penetrating peptide were efficiently delivered into the diverse primary cells. Protein delivery was improved by the addition of amodiaquine. Furthermore, purified dsRED-9K was able to penetrate all cell lineages derived from mouse embryonic stem cells efficiently. Our data may provide important insights into the design of protein-based reprogramming or differentiation protocols.

Depletion of the Pre-RC Proteins Induces Chk1/Chk2 Independent Checkpoint Responses and Apoptotic Cell Death in HeLa Cells

  • Im, Jun-Sub;Lee, Joon-Kyu
    • Animal cells and systems
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    • 제11권2호
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    • pp.129-134
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    • 2007
  • The initiation of eukaryotic DNA replication requires assembly of the pre-replicative complex (Pre-RC) through the concerted action of Orc, Cdc6, Cdt1 and Mcm2-7 complex during G1 phase. The pre-RC assembly licenses individual replication origins for the initiation of DNA replication and sufficient number of the pre-RC is essential for proper progression of S phase. However, it is not well known how cells recognize the completion of the pre-RC assembly before G1-S transition. In order to understand the cellular responses to the defects in pre-RC assembly, we depleted the known components of pre-RC proteins using the small interference RNAs in HeLa cells. Although the defects of pre-RC assembly by the depletion of the pre-RC proteins such as Orc2, Cdt1, Mcm2 & Mcm10 did not elicit the activation of Chk1- or Chk2-dependent checkpoint pathways, these cells still showed significant decrease in the cellular level of Cdc25A proteins. These results suggests that a novel checkpoint pathway exist in HeLa cells, which is not dependent upon Chk1 or Chk2 proteins and play essential roles in the cellular responses to the defects in the pre-RC assembly. Also, among those four proteins tested in this study, the depletion of Mcm10 and Cdt1 proteins significantly increased the apoptotic cell death in HeLa cells, suggesting that these proteins not only play roles in the pre-RC assembly, but also are involved in the checkpoint responses to the defects in the pre-RC assembly.

Proteomic Analysis of the Increased Proteins in Peroxiredoxin II Deficient RBCs

  • Yang, Hee-Young;Lee, Tae-Hoon
    • Reproductive and Developmental Biology
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    • 제36권1호
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    • pp.55-64
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    • 2012
  • Peroxiredoxin II (Prdx II; a typical 2-Cys Prdx) has been originally isolated from erythrocytes, and its structure and peroxidase activity have been adequately studied. Prdx II has been reported to protect a wide range of cellular environments as antioxidant enzyme, and its dysfunctions may be implicated in a variety of disease states associated with oxidative stress, including cancer and aging-associated pathologies. But, the precise mechanism is still obscure in various aspects of aging containing ovarian aging. Identification and relative quantification of the increased proteins affected by Prdx II deficiency may help identify novel signaling mechanisms that are important for oxidative stress-related diseases. To identify the increased proteins in Prdx $II^{-/-}$ mice, we performed RBC comparative proteome analysis in membrane fraction and cytosolic fractions by nano-UPLC-$MS^E$ shotgun proteomics. We found the increased 86 proteins in membrane (32 proteins) and cytosolic (54 proteins) fractions, and analyzed comparative expression pattern in healthy RBCs of Prdx $II^{+/+}$ mice, healthy RBCs of Prdx $II^{-/-}$ mice, and abnormal RBCs of Prdx $II^{-/-}$ mice. These proteins belonged to cellular functions related with RBC lifespan maintain, such as cellular morphology and assembly, cell-cell interaction, metabolism, and stress-induced signaling. Moreover, protein networks among the increased proteins were analyzed to associate with various diseases. Taken together, RBC proteome may provide clues to understand the clue about redox-imbalanced diseases.