943 Ergebnisse für: "AbFrontier"

Supplier: AbFrontier

Apolipoprotien A-I (Apo A-I) is one of the major protein components in high density lipoprotein(HDL). The molecular weight is reported to be 28.3 kDa. Apo A-I acts as a cofactor for lecithin cholesterol acyl transferase(LCAT), which is important in removing excess cholesterol from tissues and incorporating it into HDL for reverse transport to the liver. Some of the apolipoproteins act as ligands to tissue receptors, while others activate or inhibit enzymes involved in metabolic steps in the circulation or tissues. Apo A-I plays important roles in atherosclerosis, tangier disease, coronary heart disease.

Supplier: AbFrontier

α-fetoprotein (AFP) is a glycoprotein of 590 amino acids containing 3.4% carbohydrate content with a molecular weight of 61,000 – 75,000 Da. AFP is normally produced in the developing embryo and fetus by the fetal yolk sac, the fetal gastrointestinal tract, and eventually by the fetal liver. In humans, AFP levels decrease gradually after birth, reaching adult levels by 8 to 12 months. Normal adult AFP levels are low and AFP has no known function in normal adults.
The biologic role of AFP has not been defined yet. Because of its biochemical similarity to albumin, it has been postulated that AFP could be a carrier protein. It may have an immunoregulatory function during pregnancy.
Increased serum levels are found in some tumors, such as hepatocellular carcinoma (HCC), hepatoblastoma, and germ cell tumors. Although total AFP is a useful serological marker for diagnosis of HCC, the false-negative or positive rate with AFP level is very high. AFP-L3, an isoform of AFP which binds Lens culinaris agglutinin, can be particularly useful in early identification of aggressive tumors associated with HCC. AFP mRNA, the circulating genetic markers, also has been used in monitoring distal metastasis or postoperative recurrence of HCC.

Supplier: AbFrontier

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 cysteine 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).

Supplier: AbFrontier

PTEN acts as a phosphatase to dephosphorylate phosphatidylinositol (3,4,5)-trisphosphate (PtdIns (3,4,5)P3). The product of this enzymatic reaction is PtdIns(4,5)P2. This dephosphorylation is important because it results in inhibition of the AKT signaling pathway.
PTEN is a 403 amino acid protein, and a member of the large PTP (protein tyrosine phosphatase) family. PTEN crystal structure revealed that the N-terminal phosphatase domain is followed by a tightly associated C-terminal C2 domain. These two domains together form a minimal catalytic unit. The phosphatase domain contains the active site which carries out the enzymatic function of the protein, whilst the C2 domain allows PTEN to bind to the phospholipid membrane.
PTEN is one of the most commonly lost tumour suppressors in human cancer, and its deregulation is also implicated in several other diseases. Hereditary mutation of PTEN causes tumor-susceptibility diseases such as Cowden disease.

Supplier: AbFrontier

Anti-DISC1 (FRAG2) Rabbit Polyclonal Antibody

Supplier: AbFrontier

Transferrin (Tf) is a blood plasma protein for iron delivery. Transferrin functions to deliver iron to cells via a receptor-mediated endocytotic process as well as to remove toxic free iron from the blood and to provide an antibacterial, low-iron environment.
Tf protein contains 679 amino acid residues and has a molecular weight of ~79 kD, having 2 specific high affinity Fe(III) binding sites. The molecule is stabilized by 19 intra-chain disulfide bonds and is protected by three carbohydrate side chains. Although iron bound to transferrin is less than 0.1% (4 mg) of the total body iron, it is the most important iron pool, with the highest rate of turnover (25 mg/24 h).
When a Tf protein loaded with iron encounters a transferrin receptor (TfR) on the surface of a cell it binds to it and is consequently transported into the cell by endosomes. ATP-dependent proton pumps then force H+ ions into the endosomes reducing the pH to 5.5, thus promoting iron release and conformational change of the receptor enabling apo-transferrin to remain bound. The binding characteristics of the apo-Tf–TfR complex are such that the apo-Tf is released only once the complex reaches the cell surface.
Cells expressing large amounts of TfR are correspondingly competent in securing iron from Tf. Rapidly proliferating cells, as in malignancy, generally express TfR1 abundantly.
Several studies have shown a link between Tf polymorphism and susceptibility to disease. These include the rare autosomal recessive disorder atransferrinemia, cardiovascular disease (CVD) and Alzheimer’s disease.

Supplier: AbFrontier

Calcium binding proteins (CBPs) regulate intracellular levels of calcium Ca2+) ions. CBPs are involved in numerous functions, such as cell signaling, calcium uptake and transport, and cell motility. Calretinin (CR), calbindin D-28k (CB) and parvalbumin (PV) belong to the large family of Efhand calcium-binding proteins. The EF-hand is an amino acid sequence with a haracteristic threedimensional helix-loop-helix structure with high affinity for Ca2+. Calbindin D28k (calbindin) is a hexa EF-hand protein of 261 residues with 59% sequence identity to calretinin. It is a single-domain protein and the six EF hands interact extensively with one another so that they form one large globular domain. Calbindin is found in the brain and central nervous system with a distinct distribution over certain neuronal subtypes. Neuroprotective effects of calbindin has been reported in ischemic and glutamate toxicity models, primarily due to its ability to chelate calcium. Mice lacking calbindin have been shown to suffer from impaired motor coordination due to altered neuronal Ca2+-homeostasis. Notably, calbindin is found in high concentration in the kidney and in pancreatic b-cells, where it has been shown to protect against apoptosis. In osteoblasts, anti-apoptic activity of calbindin through the binding to caspase-3 has also been reported. Calbindin protects against apoptotic and necrotic cell death, suggesting its ability to buffer calcium.
Calbindin has been reported to binds Zn2+, revealing negative allosteric effect between the Zn2+- and Ca2+-binding events.

Supplier: AbFrontier

Peroxiredoxin (Prx) is a growing peroxidase family, whose mammalian members have been known to connect with cell proliferation, differentiation, and apoptosis. Many isoforms (about 50 proteins), collected in accordance to the amino acid sequence homology, particularly amino-terminal region containing active site cysteine residue, and the thiol-specific antioxidant activity, distribute throughout all the kingdoms. Among them, mammalian Prx consists of 6 different members grouped into typical 2-Cys, atypical 2-Cys Prx, and 1-Cys Prx. Except Prx 6 belonging to 1-Cys Prx subgroup, the other five 2-Cys Prx isotypes have the thioredoxin-dependent peroxidase (TPx) activity utilizing thioredoxin, thioredoxin reductase, and NADPH as a reducing system. Mammalian Prxs are 20 - 30 kilodalton in molecular size and vary in subcellular localization: Prx 1, 2, and 6 in cytosol, Prx 3 in mitochondria, Prx 4 in ER and secretion, Prx 5 showing complicated distribution including peroxisome, mitochondria and cytosol (1).

Supplier: AbFrontier

p21, also known as cyclin-dependent kinase inhibitor 1A or CDKN1A, directly inhibits the activity of cyclin-cdk2 and cyclin-cdk4 complexes. It mainly inhibits the activity of cyclin/cdk2 complexes and negatively modulates cell cycle progression. p21 also plays other fundamental roles including transcriptional regulation and the modulation of apoptosis.
p21 forms part of a family of structurally related proteins comprising p21, p27 and p57 that all share the ability to inhibit a wide range of cyclin -dependent kinase holoenzymes.
Besides its cdk inhibitor function, p21 is recognized to play a wide variety of physiological roles, many of which rely on its nuclear localization. p21 can bind to proliferating cell nuclear antigen (PCNA) thereby blocking DNA synthesis. p21 functions as a regulator of cell cycle progression at S phase. The expression of p21 is controlled by the tumor suppressor protein p53. Each of these functions of p21 is achieved through direct p21/protein interactions and the subcellular localization of p21 plays an important part in dictating the binding partners to which p21 is exposed.

Supplier: AbFrontier

Cathepsin D(CatD) is a ubiquitously expressed lysosomal aspartyl
protease involved in the normal degradation of proteins apoptosis and
autophagy. Human CatD is synthesized on the endoplasmic reticulum as
a pre-pro-enzyme. Preprocathepsin D(412aa) is cleaved and glycosylated
to form an inactive procathepsin D (392aa) and then further cleaved to
generate an active intermediate (348aa) single-chain molecule. The active
intermediate is further processed into mature two chain form of cathepsin
D, this processing step is carried out by cathepsin B or L. The two-chain
form consists of an amino terminal light chain (14 kDa) and a
carboxyl-terminal heavy chain (34 kDa). Additionally, several more amino
acids are removed from the carboxyl terminus of the 34 kDa heavy chain.
Procathepsin D (pCD), secreted from cancer cells, acts as a mitogen on
both cancer and stromal cells and stimulates their proinvasive and
pro-metastatic properties.

Supplier: AbFrontier

Integrin-linked kinase (ILK) is an adaptor and signaling protein that couples integrins to the actin cytoskeleton and coordinates signal transduction from extracellular matrix and growth factors.
By interacting with the focal adhesion proteins PINCH, paxillin, and parvin, ILK regulates integrin- mediated cell adhesion and cytoskeletal dynamics within focal adhesions to regulate cell adhesion, spreading, and migration.
ILK is involved in the suppression of apoptosis and promotion of cell survival through the phosphorylation of AKT(Ser473), GSK-3(Ser9), myosin light chain(Ser18/19), and affixin.
ILK activity is stimulated by PI3 kinase and negatively regulated by the tumor suppressor PTEN.

Supplier: AbFrontier

GPI-PLD (glycosylphosphati- dylinositol-specific phospholipase D), a 815-amino acid protein, is expressed in numerous tissues and cells and specifically cleaves GPI-anchored proteins. Liver has the highest level of GPI-PLD expression and is the primary organ contributing to GPI-PLD in the serum. GPI-PLD is abundant in serum in which it associates with apolipoproteins AI and AIV. Increased serum GPI-PLD is associated with insulin resistance and elevated serum triglycerides. Many surface proteins are attached to eukaryotic cell membranes via glycosylphosphatidylinositol (GPI) anchors that are covalently bound to the C-terminus of the protein and cleavage of the GPI moiety by GPI-PLD, only enzyme known that cleavage GPI anchor, may represent a means of regulating attachment of these proteins to the cell surface, or alternatively, their release into the extracellular environment.

Supplier: AbFrontier

Anti-PTPRR Mouse Monoclonal Antibody [clone: T10-AF4H11]

Supplier: AbFrontier

SHP1 and SHP2 represent a subfamily of non-transmembrane protein-tyrosine phosphatases (PTPs) that contain two tandem SH2 (src homology 2) domains. SHPs have two N-terminal SH2 domains (N-SH2 and C-SH2), a classic PTP domain and a C-terminal tail harboring two tyrosyl phosphorylation sites which are phosphorylated differentially by receptor and non-receptor protein-tyrosine kinases (PTKs).
Whereas SHP2 is expressed ubiquitously, SHP1 is primarily expressed in hematopoietic cells and behaves as a key regulator controlling intracellular phosphotyrosine levels in lymphocytes.
SH2 domains (particularly the N-SH2) also regulate PTP activity. Basal SHP activity is low, but addition of a phosphotyrosyl peptide that binds the N-SH2 (Tyr–P peptide ligand) markedly stimulates catalysis.
SHP1 is implicated in signaling from receptor tyrosine kinases (RTKs), cytokine receptors, chemokine receptors and integrins. SHP1-deficient bone marrow macrophages are hyper-adherent to β1- and β2-integrin ligands.
Decreased SHP1 level causes abnormal T-lymphocyte proliferation and induces various types of leukemias. Introduction of the SHP1 gene back into a leukemia cell line and a prostate cancer cell line demonstrated the tumor suppressor function of SHP1.

Supplier: AbFrontier

Peroxiredoxin (Prx) is a growing peroxidase family, whose mammalian members have been known to connect with cell proliferation, differentiation, and apoptosis. Many isoforms (about 50 proteins), collected in accordance to the amino acid sequence homology, particularly amino-terminal region containing active site cysteine residue, and the thiol-specific antioxidant activity, distribute throughout all the kingdoms. Among them, mammalian Prx consists of 6 different members grouped into typical 2-Cys, atypical 2-Cys Prx, and 1-Cys Prx. Except Prx VI belonging to 1-Cys Prx subgroup, the other five 2-Cys Prx isotypes have the thioredoxin-dependent peroxidase (TPx) activity utilizing thioredoxin, thioredoxin reductase, and NADPH as a reducing system. Mammalian Prxs are 20 - 30 kilodalton in molecular size and vary in subcellular localization: Prx I, II, and VI in cytosol, Prx III in mitochondria, Prx IV in ER and secretion, Prx V showing complicated distribution including peroxisome, mitochondria and cytosol.

Supplier: AbFrontier

Coilin is a component of the nuclear Cajar(coiled) bodies (CBs) which are involved in the function or assembly/disassembly of nucleoplasmic snRNPs.
Human coilin is a 576-amino acid protein found enriched in CBs, but is also found in large amounts in the nucleoplasm.
Coilin is a constitutive phosphoprotein that is hyperphosphorylated during mitosis and it is thought that hyperphosphorylation triggers CB disassembly during cell replication. Self-interaction and localization have been shown to depend on the phosphorylation state of coilin

Supplier: AbFrontier

The p90 ribosomal S6 kinases (RSKs) comprise a family of serine/threonine kinases that lie at the terminus of the ERK pathway. In humans, the RSK family consists of four isoforms (RSK1 to -4). RSK family members are unusual among serine/threonine kinases in that they contain two distinct kinase domains, both of which are catalytically functional. Theses kinase dimains are activated in a sequential manner by a series of phosphorylations. RSK regulates gene expression via association and phosphorylation of transcriptional regulators including c-Fos, estrogen receptor, NFkappaB/IkappaB α, cAMP-response element-binding protein (CREB).
ERK activates the C-terminal kinase of RSK, leading to activation of the N-terminal kinase. Members of the RSK family are present in the cytoplasm as well as the nucleus. Addition of growth factor to the cells results in the activation of both cytosolic and nuclear RSK and the translocation of the cytosolic RSK into the nucleus upon activation. The activation and nuclear translocation of RSK result in phosphorylation and activation of transcription factors.

Supplier: AbFrontier

Glutathione peroxidases (Gpxs) are ubiquitously expressed proteins which catalyze the reduction of hydrogen peroxides and organic hydroperoxides by glutathione. There are several isoforms which differ in their primary structure and localization. The classical cytosolic/ mitochondrial GPx1 (cGPx) is a selenium-dependent enzyme, first of the GPx family to be discovered. GPx2, also known as gastrointestinal GPx (GI-GPx), is an intracellular enzyme expressed only at the epithelium of the gastrointestinal tract. Extracellular plasma GPx (pGPx or GPx3) is mainly expressed by the kidney from where it is released into the blood circulation. Phospholipid hydroperoxide GPx4 (PH-GPx) expressed in most tissues, can reduce many hydroperoxides including hydroperoxides integrated in membranes, hydroperoxy lipids in low density lipoprotein or thymine. All mammalian GPx family members, except for the recently described Cys containing GPx3 and epididymis-specific secretory GPx (eGPx or GPx5) isoforms, possess selenocysteine at the active site.

Supplier: AbFrontier

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.
The most common form of NF-κB is the p50/RelA heterodimer, although other forms of NF-κB dimers, such as p50/p50, p52/p52, p52/RelA, p50/c-Rel, c-Rel/c-Rel, p52/RelB, and p50/RelB, have also been identified in some types of cells.
The primary role of NF-κB is to maintain normal cellular functions that range from cell-to-cell communication to cell motility, cell cycle progression, and cell lineage development. The activity of NF-κB is tightly regulated by interaction with inhibitory IκB proteins.

Supplier: AbFrontier

β-Catenin was a cytosolic protein originally identified through its association with the cadherin class of cell-adhesion proteins. β-Catenin has two key cellular functions; one plays direct role in cell adhesion/migration, bridging between cadherins and tactin cytoskeleton. The other plays as a transcription cofactor with T cell factor/lymphoid enhancer factor (TCF/LEF) in the Wnt pathway. Wnt are powerful regulators of cell proliferation and differentiation, and their signaling pathway involves proteins that directly participate in both gene transcription and cell adhesion. Activation of Wnt signaling leads to inhibition of Glycogen synthase-3β (GSK-3β) activity, resulting in accumulation of cytoplasmic (signaling) β-Catenin, which becomes available to bind the TCF/LEF family of transcription factors and to induce target gene expression. In the absence of Wnt signaling, A complex of axin and casein kinase-I(CK-I) induces β-Catenin phospho- rylation at a single site: serine 45(Ser45). This likely serves as a priming site for subsequent phosphorylation by GSK3b. And then β-Catenin is phosphorylated by GSK-3β at Ser33/37 and Thr41. These serine/threonine phosphylation is required for the phosph rylation-dependant degradation of β catenin via ubiquitin-proteosome pathway. Mutation of these phosphorylation sites in β-Catenin has been found in many tumor cell lines.

Supplier: AbFrontier

Anti-Alpha/ Beta-Synuclein Rabbit Polyclonal Antibody

Supplier: AbFrontier

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.

Supplier: AbFrontier

Check point kinase 1 (Chk1) is a serine / threonine protein kinase and a key mediator in the DNA damage-induced checkpoint network. Chk1 is an evolutionarily conserved protein kinase that functions to ensure genomic integrity upon genotoxic stress. When the G2 or S checkpoint is abrogated
by the inhibition of Chk1, p53-deficient cancer cells undergo mitotic catastrophe and eventually apoptosis, whereas normal cells are still arrested in the G1 phase. Thus, Chk1 inhibitors can preferentially
potentiate the efficacy of DNA damaging agents in cancer cells, and Chk1 is an attractive therapeutic target for cancer treatment, especially since approximately 50% of all human cancers are p53-deficient.

Supplier: AbFrontier

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.

Supplier: AbFrontier

Lactate dehydrogenase (LDH) is the enzyme in the glycolytic pathway that converts pyruvate to lactate with concomitant interconversion of NADH and NAD+. In mammals, the enzyme is encoded by three genes: LDHA (M or muscle form), LDHB (H or heart form), and LDHC (X or testis form). The three human LDHs have 84–89% sequence similarities and 69–75% amino acid identities. There are five different LDH isoenzymes based on the proportion of M and H chains existing in the LDH tetrameric structure.
The LDHA is hypoxia inducible and its expression is directly controlled by the transcriptional activity of the hypoxia inducible factor 1a (HIF1a). LDHB is also known to be upregulated in many cancers.

Supplier: AbFrontier

Well known as detoxification enzymes, the glutathione transferases(GST) also function in prostaglandin and steroid hormone synthesis. The enzymes are dimmers of 25kDa subunits. There are three major groups of GSTs: canonical(or cytosolic) GSTs(cGSTs), mitochondrial GSTs, and microsomal GSTs. GSTs play a role in the metabolism of drugs, pesticides and other xenobiotics.
GST is also a widely used fusion partner, since it offers both an easily detectable tag and a simple purification process that has a minimal with little effect on the biological function of the protein of interest. Recombinant hybrids containing a polypeptide fusion partner (termed “affinity tag”) to facilitate the purification of the target polypeptides are widely used. Epitope tags are useful for the labeling and detection of proteins using immunoblotting, IP and immunostaining techniques. Due to their small size, they are unlikely to affect the tagged protein’s biochemical properities. Numerous vectors containing GST-tags have been developed for both prokaryotic and eukaryotic systems over the past decade.

Supplier: AbFrontier

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, such as the MAP kinase family. Recently, increasing attention has been focused on the growing family of PTPs. Like PTKs, PTPs have been implicated in cell signaling, cell growth and proliferation, and oncogenic transformation. Moreover, some PTPs can be involved in cell cycle regulation and embryogenesis.
Dual specificity phosphatases (DSPs) are an emerging subclass of the protein tyrosine phosphatase (PTP) gene superfamily, which appears to be selective for dephosphorylating the critical phosphothreonine and phosphotyrosine residues. The prototypical DSP is the VH1 gene in vaccinia virus expressed in late-stage viral infection.
A shallow active site pocket in VHR allows for the hydrolysis of phosphorylated serine, threonine, or tyrosine protein residues, whereas the deeper active site of protein tyrosine phosphatases (PTPs) restricts substrate specificity to only phosphotyrosine.

Supplier: AbFrontier

Enolase (2-phosphogly-cerate hydrolyase or phosphopyruvate hydrates) is a glycolytic enzyme that catalyzes the dehydration and conversion of 2-phosphoglycerate to phosphoenolpyruvate. It comprises three distinct subunits, α, β and γ. The γγ and αγ dimeric forms of enolase, referred to as neuron-specific enolase(NSE), are localized mainly in neurons and neuroectodermal tissue. NSE has a high stability in biological fluids and can easily diffuse to the extracellular medium and cerebrospinal fluid(CSF) when neuronal membranes are injured. NSE is used clinically as a sensitive and useful marker of neuronal damage in several neurological disorders including stroke, hypoxic brain damage, status epilepticus, Creutzfeldt-Jakob disease, and herpetic encephalitis.

Supplier: AbFrontier

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).

Supplier: AbFrontier

Serum amyloid P component (SAP) is a normal plasma protein and a universal non-fibrillar constituent of amyloid deposits. SAP is a member of the pentraxin protein family which includes C-reactive protein. Human SAP is secreted and catabolized only by hepatocytes, and consists of five identical non-covalently associated subunits, each with a molecular mass of 25 kDa, which are non-covalently associated in a pentameric disc-like ring. SAP is a calcium-dependent ligand binding protein, which binds to DNA and chromatin, and to all known types of amyloid fibrils accounting for its specific accumulation in amyloid deposits. Serum amyloid P component scintigraphy is a non-invasive and quantitative method for imaging amyloid deposits, which produces diagnostic images in most patients with systemic amyloidosis, and can be used repeatedly to monitor the course of the disease.