943 Results for: "AbFrontier"

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The mammalian thioredoxin reductases (TrxRs) are a family of selenocysteine-containing pyridine nucleotide-disulfide oxidoreductases. All the mammalian TrxRs are homologous to glutathione reductase with respect to primary structure including the conserved redox catalytic site (-Cys-Val-Asn-Val-Gly-Cys-) but distinctively with a C-terminal extension containing a catalytically active penultimate selenocysteine (SeCys) residue in the conserved sequence(-Gly-Cys-SeCys-Gly). TrxR is homodimeric protein in which each monomer includes an FAD prosthetic group, a NADPH binding site and a redox catalytic site. Electrons are transferred from NADPH via FAD and the active-site disulfide to C-terminal SeCys-containing redox center, which then reduces the substrate like thioredoxin. The members of TrxR family are 55 - 58 kilodalton in molecular size and composed of three isoforms including cytosolic TrxR1, mitochondrial TrxR2, and TrxR3, known as Trx and GSSG reductase (TGR). TrxR plays a key role in protection of cells against oxidative stress and redox-regulatory mechanism of transcription factors and various biological phenomena (1).

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Lactoferrin(Lf), one of transferrin family, is found in external fluids, including milk and mucosal secretions, and prominent components of the secondary granules of neutrophils. Lf consists of a single polypeptide chain (approximately 80 kDa) folded into two structurally homologous lobes, each of which can reversibly bind one ferric ion (Fe3+). Lf plays a central role in iron metabolism and host defense system against microbial infection.

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14-3-3, a family of acidic and soluble proteins, highly conserved in amino acid sequences from yeast to mammals, is expressed in all eukaryotic cells. Seven isoforms(beta, gamma, epsilon, eta, zeta, sigma and tau/phi) encoded by seven distinct genes are identified in mammals and forms homo- and hetero- dimeric cup-shaped structures. As 14-3-3 is interacted with more than 100 binding partners, it regulates key proteins involved in various biological processes such as signal trans-duction, cell cycle, transcriptional control, cell proliferation, apoptosis, and ion channel physiology. Most  14-3-3 requires phosphorylation of serine or threonine residues in the target sequence. This protein is abundantly expressed in the brain and has been detected in the cerebrospinal fluid of patients with different neurological disorders.

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Tumor necrosis factor (TNF)-α is an important cytokine in the innate immune response produced by macrophages, neutrophils, fibroblasts, keratinocytes, NK cells, T and B cells, and tumour cells. TNF-α mediates host responses in acute and chronic inflammatory conditions, and is a mediator of protection from infection and malignancy. TNF-α causes apoptotic cell death, cellular proliferation, differentiation, inflammation, tumorigenesis, and viral replication.
TNF-α is initially produced as a biologically active 26 kDa transmembrane protein, which is subsequently cleaved, principally by TNF-α-converting enzyme (TACE), to release the 17kDa free protein. These proteins are arranged in biologically active homotrimers that act on the ubiquitously expressed TNF-α receptors 1 and 2 (TNFR1 and TNFR2). These 17 kDa TNF protomers are composed of two antiparallel β-pleated sheets with antiparallel β-strands, forming a 'jelly roll' β-structure, typical for the TNF family.
TNF-R1 is constitutively expressed in most tissues, and can be fully activated by both the membrane-bound and soluble trimeric forms of TNF, while TNF-R2 is only found in cells of the immune system and respond to the membrane-bound form of the TNF homotrimer. Although their extracellular domains share structural and functional homology, their intracellular domains are distinct.
Tumor necrosis factor promotes the inflammatory response, which in turn causes many of the clinical problems associated with autoimmune disorders such as rheumatoid arthritis, ankylosing spondylitis, Crohn's disease, psoriasis and refractory asthma. These disorders are sometimes treated by using TNF inhibitors such as infliximab (Remicade) or adalimumab (Humira).

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Shc is a prototype adapter protein that is expressed from the earliest stages of T-cell development. Shc becomes rapidly tyrosine phosphorylated after T-cell receptor (TCR) engagement.
Three shc genes have been identified in mammals and their gene products have been referred to as ShcA, ShcB and ShcC. ShcA is ubiquitously expressed, while shcB and ShcC expression appear limited to neuronal cells. ShcA is expressed as three isoforms of about 46, 52 and 66 kDa.
Shc is composed of an N-terminal PTB, a central collagen-homology (CH) domain and a C-terminal SH2 domain. The 66 kDa isoform of ShcA is expressed in most cells except in the hematopoietic lineage and contains an additional amino-terminal CH-like region.
The tyrosine phosphorylation of Shc has been noticed upon engagement of numerous cell surface receptors such as growth factor receptors, antigen receptors, cytokine receptors, G-protein coupled receptors and hormone receptors. The involvement of ShcA in the Ras signaling pathway is initiated by the tyrosine-phosphorylation of the receptor protein tyrosine kinases (RPTKs) and subsequent interaction with Grb2 and Ras guanine nucleotide exchange factor, Sos. The Shc : Grb2 : Sos complex gets localized to the membrane through the interaction of Shc with the phosphorylated receptor. Membrane-bound Sos then activates Ras by catalysing GDP/GTD exchange. GTP-bound Ras then triggers downstream events, which include Raf, the mitogen-activated protein kinases (MAPKs) and MAPK kinase (MEK).

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Myoglobin is a cytoplasmic hemoprotein, expressed solely in cardiac myocytes and oxidative skeletal muscle fibers, that reversibly binds O₂ byits heme (iron-containing porphyrin) prosthetic group in the center aroundwhich the remaining apoprotein folds. Myoglobin is a single-chain globular protein of 153 amino acids and an early indicator of cardiac ischemia that achieves maximal sensitivity 3 to 4 hours after symptom onset.

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Hematopoietic progenitor kinase 1 (HPK1) is a 97 kDa serine/threonine protein kinase expressed only in hematopoietic cells and tissues. HPK1 is comprosed of a STE20-like kinase domain in its N-terminus, four proline-rich motifs (-P-x-x-P-), a caspase cleavage site, and a distal C-terminal Citron homology domain. The proline-rich motifs are capable of binding proteins that contain SH3 domains.
HPK1 is involved in many cellular signaling cascades that include MAPK signaling, antigen receptor signaling, apoptosis, growth factor signaling, and cytokine signaling. HPK1 binds many adaptor proteins including members of the Grb2 family, Nck family, Crk family, SLP-76 family, and actin-binding adaptors. HPK1 contains 13 potential tyrosine phosphorylation residues, some of which may be phosphorylated by ZAP-70, which provide potential docking sites for SH2 domains containing proteins.
HPK1 is activated by both EGF and PDGF stimulation where adaptor proteins are involved in mediating the localization of effector molecules to cell surface receptors.
Activation-induced cell death (AICD)-resistant T cells contain full-length HPK1, while AICD-sensitive T cells have HPK1-C (cleaved form). HPK1 might be a possible molecular switch used to discriminate between the extrinsic pathway involving death receptors and the intrinsic pathway determined by the ratio between anti- and pro-apoptotic Bcl-2 family members.

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TRBP (transactivation response RNA binding protein) is a protein that increases HIV-1 expression and replication by inhibition of the interferon-induced protein kinase PKR. TRBP overexpression is associated with reduced abundance of phosphorylated PKR and stimulation of protein translation.
TRBP has a physiological role in spermatogenesis and growth control during development. It is oncogenic upon overexpression, likely because of its association with PKR, with the PKR activator PACT, and with the tumor suppressor Merlin. TRBP was identified as a merlin interacting protein by Gal4-based yeast two-hybrid screening of a human adult brain cDNA library. Merlin can inhibit tumorigenesis mediated by TRBP and can regulate the protein translation pathways controlled by TRBP.
Dicer is a key enzyme involved in RNA interference (RNAi) and microRNA (miRNA) pathways. Ago-2, a member of the Argonaute family, Dicer and TRBP comprise the catalytic core of the RNA induced silencing complex (RISC).

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The mammalian thioredoxin reductases (TrxRs) are a family of selenocysteine-containing pyridine nucleotide-disulfide oxido-reductases. All the mammalian TrxRs are homologous to glutathione reductase with respect to primary structure including the conserved redox catalytic site (-Cys-Val-Asn-Val-Gly-Cys-) but distinctively with a C-terminal extension containing a catalytically active penultimate selenocysteine (SeCys) residue in the conserved sequence(-Gly-Cys-SeCys-Gly). TrxR is homodimeric protein in which each monomer includes an FAD prosthetic group, a NADPH binding site and a redox catalytic site. Electrons are transferred from NADPH via FAD and the active-site disulfide to C-terminal SeCys-containing redox center, which then reduces the substrate like thioredoxin. The members of TrxR family are 55 – 58 kilodalton in molecular size and composed of three isoforms including cytosolic TrxR1, mitochondrial TrxR2, and TrxR3, known as Trx and GSSG reductase (TGR). TrxR plays a key role in protection of cells against oxidative stress and redox-regulatory mechanism of transcription factors and various biological phenomena (1).

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Sequential activation of protein kinases within the MAPK (mitogen-activated protein kinases) cascades is a common mechanism of signal transduction in many cellular processes. The ERK signaling cascade is a central MAPK pathway that plays a role in the regulation of various cellular processes such as proliferation, differentiation, development, learning, and survival. Mitogen-activated protein kinase kinases (MAPKK) phosphorylate MAPK. MEK (MAP kinase or ERK kinase) is the immediate upstream activator kinase of ERK.
MEK6 encodes a 334-amino acid protein with 82% identity to MKK3. MEK6 is highly expressed in skeletal muscle like many other members of this family, but in contrast to MKK3 its expression in leukocytes is very low. The human MEKs (MEK1, MEK2, MEK3) show remarkably different activity toward ERKl and ERK2. MEK2 is the most active ERK activator. MEK3 is inactive toward ERKl or ERK2. MEK3, MEK4, and MEK6 phosphorylate and activate p38 MAP kinase. The p38 mitogen-activated protein (MAP) kinase signal transduction pathway is activated by proinflammatory cytokines and environmental stress. Transcription factors such as ATF2 and Elk-1 are targets of the p38 MAP kinase signal transduction pathway.

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NF-κB (Nuclear Factor kappa B) is a nuclear transcription factor found in all cell types and is involved in cellular responses to stimuli such as stress, cytokines, free radicals, ultraviolet irradiation, and bacterial or viral antigens. NF-κB plays a key role in regulating the immune response to infection. Consistent with this role, incorrect regulation of NF-κB has been linked to cancer, inflammatory and autoimmune diseases, septic shock, viral infection and improper immune development. There are five members in the NF-κB family: NF-κB1, NF-κB2, RelA (also named p65), RelB, and c-Rel. RelA(p65) subunit of NF-κB is a crucial regulator of apoptosis. RelA subunit mediates resistance to programmed cell death induced by many stimuli, including TNF, chemotherapy agents and ionizing radiation, through inducing the expression of a wide variety of anti-apoptotic genes.

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SHP2 is a tyrosine phosphatase containing two tandem SH2 (src homology 2) domains. Protein tyrosine phosphatases (PTPs) are a group of enzymes that remove phosphate groups from phosphorylated tyrosine residues on proteins. Together with tyrosine kinases, PTPs regulate the phosphorylation state of many important signaling molecules.
SHP1 and SHP2 represent a subfamily of non-transmembrane PTPs that contain two SH2 domains followed by a PTP domain. Tyrosine phosphorylation of SHP2 is required for normal ERK activation in response to some growth factors. In the inactive state, the N-terminal SH2 domain binds the PTP domain and blocks access of potential substrates to the active site. This auto-inhibition is relieved by the binding of phosphopeptides to SH2 domain, resulting in activation of phostphatase activity.
Noonan syndrome characterized by an abnormal face, short stature and cardiac abnormalities is due to the mutations of N-terminal SH2 domain or PTP domain. SHP2 mutations might also cause some leukemia, and could be important in pathogenesis by Helicobacter pylori, the major cause of gastric ulcer and carcinoma.

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The Notch signaling pathway is important for cell-cell communication, which involve gene regulation mechanisms that control multiple cell differentiation processes during embryonic and adult life. It critically influences cell proliferation, differentiation, and apoptosis in metazoans. The hairy and enhancer of split (HES) family is a basic helix-loop-helix (bHLH) type trancriptional repressor and acts as Notch effectors by negatively regulating expression of downstream target genes such as tissue-specific transcription factors. HES-1 is an upstream negative regulator of REST expression. Silencing of the transcriptional repressor REST is required for terminal differentiation of neuronal and β-cells.
Recent integrative genomic analyses on HES/HEY family suggest that HES1 and HES3 are target genes of the embryonic stem cell-specific network of transcription factors, and that HES1, HES5, HEY1, HEY2 and HEYL are target genes of Notch signaling pathway.

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The casein kinase I (CKI) family of serine/threonine protein kinases is highly conserved from yeast to humans. The CKI family is involved in many diverse and important cellular functions, such as regulation of membrane transport, cell division, DNA repair, circadian rhythms, and nuclear localization.
The name of the enzyme family was originated from the convenience of casein as a substrate since the earliest days of research on protein phosphorylation.
Casein kinase 2 (CK2) is a ubiquitous, highly conserved, essential serine/threonine kinase which has been implicated in cell cycle control, DNA repair, regulation of the circadian rhythm and other cellular processes.
CK2 is a tetramer of two α subunits and two β subunits. The α subunits have the catalytic kinase domain. Loss of the α‘ catalytic subunit produces male infertility, and loss of the single β regulatory subunit is
early embryonic lethal.
CK2 appears to be upregulated in most cancers and the promotion of tumorigenesis by the overexpression of CK2 has been reported in transgenic mice.

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Creatine kinase (CK), also known as phosphocreatine kinase or creatine phosphokinase (CPK) is an enzyme expressed by various tissue types. It catalyzes the reversible transfer of the N-phosphoryl group from phosphocreatine (PCr) to ADP to regenerate ATP. Creatine kinase plays a key role in the energy homeostasis of cells with intermittently high, fluctuating energy requirements, such as skeletal and cardiac muscle cells, neurons, photoreceptors, spermatozoa and electrocytes.
Creatine kinase consists of two subunits, which can be either B (brain type) or M (muscle type). Therefore, three different cytosolic isoenzymes exist: CK-MM, CK-BB and CK-MB. Cytosolic CK isoenzymes are always co-expressed in a tissue-specific fashion together with a mitochondrial isoform. Skeletal muscle expresses CK-MM (98%) and low levels of CK-MB (1%). The heart muscle expresses CK-MM at 70% and CK-MB at 25-30%. CK-BB is expressed in all tissues at low levels.
Cytosolic CKs, in close conjunction with Ca2+-pumps, play a crucial role for the energetics of Ca2+-homeostasis. Octameric mitochondrial Mi-CK binds and crosslinks mitochondrial membranes. The CK system is
regulated by AMP-activated protein kinase via PCr/Cr and ATP/AMP ratios.
The cardiac-specific isoenzyme of creatine kinase, CK-MB, is a biomarker for myocardial infarction along with other markers such as cardiac Troponin I and myoglobin. The introduction of immunologic mass determination of CK-MB was a major breakthrough that replaced the traditional enzymatic assay.

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ROCK, Rho-associated coiled-coil forming kinases, is a protein serine/threonine kinase that is activated when bound to the GTP-bound form of Rho. The small GTPase Rho regulates formation of focal adhesions and stress fibers of fibroblasts, as well as adhesion and aggregation of platelets and lymphocytes by shuttling between the inactive GDP-bound form and the active GTP-bound form. Rho is also essential in cytokinesis and plays a role in transcriptional activation by serum response factor. ROCK, as a downstream effector of Rho, phosphorylates and activates LIM kinase, which in turn, phosphorylates cofilin, inhibiting its actin-depolymerizing activity. ROCK2 regulates cytokinesis, smooth muscle contraction, the formation of actin stress fibers and focal adhesions, and the activation of the c-fos serum response element.

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Histone H2A is one of the 5 main histone proteins involved in the structure of chromatin in eukaryotic cells. The nucleosome in which an 147 base-pairs of DNA are wrapped 1.7 times around a central core of eight histone protein molecules forms the basic building block of chromatin. Histone octamer consists of two copies each of H2A, H2B, H3, and H4 histones.
Histone H2A variant H2AX, a component of the nucleosome core structure that comprises 10%–15% of total cellular H2A, has a special role in DNA repair, cell cycle checkpoints, regulated gene recombination events, and tumor suppression.
H2AX can be phosphorylated on Ser 1, acetylated on Lys 5 and ubiquitinated on Lys 119. But what makes H2AX unique is a highly conserved serine 139 residue which is rapidly phosphorylated upon the exposure of cells to DNA damage. H2AX is phosphorylated by ATR in response to DNA replication stress, and primarily by ATM in response to low levels of ionizing radiation. Phosphorylation of H2AX increases the likelihood of assembling a functional repair complex by increasing the local concentration of repair factors near the lesion.

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The inhibitor of caspase-3-activated DNase (ICAD) is a caspase-3 substrate that controls nuclear apoptosis. ICAD has two isoforms: a functional isoform of M.W. 45kDa, ICAD-L/DNA fragmentation factor (DFF) 45; and a M.W.35kDa isoform, ICAD-S/DFF35. Although both ICAD-L and ICAD-S can bind and inhibit CAD, only ICAD-L was reported to be functional. ICAD is cleaved to be inactivated and allow caspase-activated DNase (CAD) to execute nuclear internucleosomal apoptotic DNA fragmentation. In non-apoptotic cells, CAD is complexed with its inhibitor, ICAD. The activation of the CAD/ICAD complex occurs through the caspase 3-mediated cleavage of ICAD at residues 117 and 224, which results in three ICAD fragments that are then released from CAD. In addition to its DNase inhibitory activity, ICAD acts as a CAD-specific folding chaperone. There are recent reports that ICAD is a potential target for restoring a normal apoptotic signal transduction pathway in colon and brain cancer cells.

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Thioredoxins (Trx) are small, multi-functional proteins with oxidoreductase activity and are ubiquitous in essentially all living cells. Trx contains a redox-active disulfide/dithiol group within the conserved Cys-Gly-Pro-Cys active site. The two cystein residues in the conserved active centers can be oxidized to form intramolecular disulfide bonds (1). Reduction of the active site disulfide in oxidized Trx is catalyzed by Trx reductase with NADPH as the electron donor. The reduced Trx is a hydrogen donor for ribonucleotide reductase, the essential enzyme for DNA synthesis, and a potent general protein disulfide reductase with numerous functions in growth and redox regulations (2). Specific protein disulfide targets for reduction by Trx include protein disulfide –isomerase (PDI) (3) and a number of transcription factors such as p53 (4), NF-kB (5) and AP-1 (T1-151). Trx is also capable of removing H2O2, particularly when it is coupled with either methionine sulfoxide reductase or several isoforms of peroxiredoxins (6-7).

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ROCK, Rho-associated coiled-coil forming kinases, is a protein serine/threonine kinase that is activated when bound to the GTP-bound form of Rho. The small GTPase Rho regulates formation of focal adhesions and stress fibers of fibroblasts, as well as adhesion and aggregation of platelets and lymphocytes by shuttling between the inactive GDP-bound form and the active GTP-bound form. Rho is also essential in cytokinesis and plays a role in transcriptional activation by serum response factor. ROCK, as a downstream effector of Rho, phosphorylates and activates LIM kinase, which in turn, phosphorylates cofilin, inhibiting its actin-depolymerizing activity. ROCK1 is involved in diverse cellular functions, including smooth muscle contraction, actin cytoskeleton organization, cell adhesion and motility, and gene expression.

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Protein phosphatase-1(PP1) is one of the major Ser/Thr protein phosphatases and is ubiquitous in eukaryotic cells. PP1 is localized to its site of action by interacting with targeting or regulatory proteins, a majority of which contains a primary docking site referred to as the RVXF/W motif. The catalytic subunit of PP1 exists as three isoforms, PP1a, PP1b, and PP1r. The PP1 catalytic subunits are small proteins of 37kDa, which are highly conserved, with their main differences falling in the C-term. The PP1 catalytic subunit exists in the cell in complex with a large number of targeting/regulatory subunits, thereby generating different enzyme forms that allow it to perform a diverse number of cellular functions.

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Moesin (for membrane-organizing extension spike protein) is a member of the EMR protein family which includes ezrin and radixin. ERM proteins appear to function as cross-linkers between plasma membranes and actin-based cytoskeletons.

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Human carboxypeptidase N (CPN) [(EC) 3.4.17.3], a member of the CPN/E subfamily of “regulatory” metallo-carboxypeptidases, is a zinc metalloprotease, which cleaves basic amino acids, lysine and arginine, from the carboxy-terminus of biologically active peptides and proteins.
CPN is an extracellular glycoprotein synthesized in the liver and secreted into the blood, where it controls the activity of vasoactive peptide hormones, growth factors and cytokines by specifically removing C-terminal basic residues. Human CPN was discovered as an enzyme that inactivates bradykinin by cleaving its carboxy-terminal arginine and was also referred to as kininase I.
CPN is a major inactivator of anaphylatoxins C3a, C4a and C5a and also cleaves off C-terminal Lys residues from larger protein substrates, such as the M and B subunits of creatine kinase, released from the heart after myocardial infarction.
CPN is a tetramer (280 kDa) comprised of two heterodimers each
consisting of a catalytic CPN1(48 – 55 kDa) and non-catalytic CPN2 (83kDa) subunit.The CPN2 subunit keeps the smaller catalytic subunit in the circulation and protects it against inactivation at 37 °C. The CPN2 subunit may also promote the cleavage of higher molecular mass plasma protein substrates by the catalytic CPN1 subunit.
The most conserved region of the carboxypeptidase proteins is the active site. All mammalian carboxypeptidases contain a zinc binding site, a substrate binding site, an amino acid involved in peptide specificity, and an amino acid involved in catalytic activity of the protein.
Patients with reduced CPN level present chronic recurrent angioedema, which is unrelated to diet or environment.

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Bcl-2 (B-cell lymphoma 2) family govern mitochondrial outer membrane permeabilization (MOMP) and can be either pro-apoptotic (Bax, BAD, Bak, Bid and Bok) or anti-apoptotic (Bcl-2, Bcl-xL, and Bcl-w). The mitochondrial release of cytochrome c through anion channel is regulated by Bcl-2 and Bcl-xL. The Bcl-2 family of proteins are key regulators of many signals leading to caspase, which when activated cause cellular destruction by cleaving a range of vital cellular substrates.
The members of the Bcl-2 family share one or more of the four characteristic domains of homology entitled the Bcl-2 homology (BH) domains (named BH1, BH2, BH3 and BH4).
The Bcl-2 gene has been implicated in a number of cancers, including melanoma, breast, prostate, and lung carcinomas, as well as schizophrenia and autoimmunity. It is also thought to be involved in resistance to conventional cancer treatment.
Apoptosis is an important component of the sequence of events during which anticancer drugs induce an antitumor response. The molecular mechanism for drug-induced apoptosis is associated with a mitochondrial dysfunction that is characterized by an increase in MOMP and a release of cytochrome c from mitochondria, indicating that Bcl-2 plays a critical role in anticancer drug-induced apoptosis.

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The complement system is a part of the larger immune system and three biochemical pathways are present: the classical complement pathway, the alternative pathway, and the mannose-binding lectin pathway.
Complement component C4 is an essential component of humoral immune response. In its activated form, C4b becomes a subunit of the C3 convertase, which is an enzymatic complex that activates C3 of the classical and lectin complement activation pathways. The classical pathway is initiated by the activation of the C1-complex (C1q, C1r and C1s) by C1q's binding to antibody-antigen. The C1-complex now binds to and splits C2 and C4 producing C2a and C4b. C4b and C2a bind to form C3-convertase. Production of C3-convertase leads to cleavage of C3 into C3a and C3b and C3b joins with the C3 convertase to make C5 convertase. Human C4 is the most polymorphic protein of the complement system. Complement C4 exists as two isotypes, C4A (acidic) and C4B (basic). Although the sequence identity is very high, they have different hemolytic activities, covalent affinities to antigens and immune complexes, and serological reactivities. Each C4 contains β chain, α chain, C4a anaphyltoxin, C4b, and γ chain.
C4-deficient mice shows incomplete clearance of microbial attack and C4-deficiency in human shows increased autoimmune diseases.

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Anti-NF2 Mouse Monoclonal Antibody [clone: AF1G4]

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Vitronectin is an 75 kDa glycoprotein consisting of 459 amino acid residues. It is abundant in blood plasma and the extracellular matrix. Vitronectin contains three glycosylation sites that contribute approximately 30% of its molecular mass. It circulates as a single-chain (75 kDa) and two-chain (10 and 65 kDa) forms under reducing conditions. Under non-reducing conditions, the N-terminal 65 kDa and C-terminal 10 kDa fragments are linked by a single disulfide bond .
Vitronectin has been implicated as a regulator of many diverse physiological processes including coagulation, fibrinolysis, pericellular proteolysis, complement dependent immune response, cell attachment and spreading. Cell adhesion and migration are directly involved in cancer metastasis and tumor malignancy.
The Somatomedin B domain of Vitronectin binds to Plasminogen activator inhibitor-1 (PAI-1), and stabilizes it. Thus vitronectin serves to regulate proteolysis initiated by plasminogen activation. Additionally vitronectin is a component of platelets and is thus involved in hemostasis via heparin binding which neutralizing antithrombin III inhibition of thrombin and factor Xa. Vitronectin contains an RGD (45-47) sequence which is a binding site for membrane bound integrins, which serve to anchor cells to the extracellular matrix.

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The Rb protein (pRb, 110kDa) is a tumor suppressor, which plays a pivotal role in the negative control of the cell cycle and in tumor progression. pRb is responsible for a major G1 checkpoint, blocking S-phase entry and cell growth. pRb prevents the cell from replicating damaged DNA by preventing its progression through the cell cycle into its S phase or progressing through G1 phase. pRb can actively inhibit cell cycle progression when it is dephosphorylated while this function is inactivated when pRb is phosphorylated. pRb is activated near the end of mitosis (M phase) when a phosphatase dephosphorylates it, allowing it to bind E2F. The pRb protein represses gene transcription, required for transition from G1 to S phase, by directly binding to the transactivation domain of E2F and by binding to the promoter of these genes as a complex with E2F.

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Transthyretin (TTR, 55 kDa homotetramer) is a thyroid hormone-binding protein that transports thyroxine (T4) from the bloodstream to the brain. TTR was originally called prealbumin because it ran faster than albumin on electrophoresis gels. . TTR is produced in the liver and circulates in the bloodstream, where it binds retinol and thyroxine. TTR is suggested that plays an essential role in brain function. The protein consists of around 130 amino acids, which assemble as a homotetramer that contains an internal channel in which T4 is bound. Within this complex, T4 appears to be transported across the blood-brain barrier, where, in the choroid plexus, the hormone stimulates further synthesis of transthyretin. The protein then diffuses back into the bloodstream, where it binds T4 for transport back to the brain. TTR is known to be associated with the amyloid diseases senile systemic amyloidosis (SSA), familial amyloid polyneuropathy (FAP), and familial amyloid cardiomyopathy (FAC).

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α-1-Acid glycoprotein (AGP) is a protein with a molecular weight of 41~43 kDa and is heavily glycosylated (45%). Due to the presence of sialic acids, it is negatively charged (pI=2.7-3.2). AGP is one of the major acute phase proteins in humans. As most acute phase proteins, its serum concentration increases in response to systemic tissue injury, inflammation or infection, and these changes in serum protein concentrations have been correlated with increases in hepatic synthesis. Also, its glycosylation pattern can change depending on the type of inflammation. The biological function of AGP remains unknown; however, AGP is believed to regulate the interaction between blood cells and endothelial cells, and regulates the extravasation of the cells during infection and inflammation.