943 Results for: "AbFrontier"
Anti-GPX3 Mouse Monoclonal Antibody [clone: 55A]
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 (1). Extracellular plasma GPx (pGPx or GPx3) is mainly expressed by the kidney from where it is released into the blood circulation (2). 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 (3). 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 (4-5).
Expand 1 Items
Anti-Ubiquitin +1 Rabbit Polyclonal Antibody
Supplier: AbFrontier
Ubiquitin+1(Ub+1) is a novel mutant form of ubiquitin that can be produced through a process known as molecular frame shift. Ub+1 can be polyubiquitinated to produce aberrant polyubiquitin chains that inhibit the 26S proteasome. Especially ub+1 is accumulated in aggregates containing amyloid-β and phosphorylated-tau. Elevated expression of Ub+1 mRNA and protein has been observed in the brains of patients with Alzheimer's disease. Also Ub+1 acts as an aggravating factor in polyglutamine-induced neurodegeneration.
Expand 1 Items
Anti-HSPA13 Mouse Monoclonal Antibody [clone: 16A12]
Supplier: AbFrontier
The Heat shock protein 70(HSP70) family was found in many intracellular compartments. Members of this protein occur in chloroplasts, endoplasmic reticulum, mitochondria, and cytosol. These proteins are induced by a variety of biological stresses, including heat stress, in every organism. HSP70 serves a variety of roles: 1) It acts as molecular chaperones facilitating the assembly of multi-protein complexes, 2) It participates in the translocation of polypeptides across cell membranes and to the nucleus 3) It aids in the proper folding of nascent polypeptide chains. HSP70 is mitochondrial import machinery and plays key roles in the cytosolic endoplasmic reticulum. Recently, extracellular localized HSP have been found to play key roles in the induction of a cellular immune response.
Expand 1 Items
Anti-A2M Mouse Monoclonal Antibody [clone: 3D1]
Supplier: AbFrontier
α2-Macroglobulin (α2M), is a 720-kDa homotetrameric glycoprotein composed of four identical 180 kDa subunit. α2M shares with other α-macroglobulins, like the complement components C3 and C4 and the pregnancy zone protein PZP, an extraordinary binding capacity for a variety of ligands. This allows the α-macroglobulins to serve as humoral defense barriers against foreign peptides in the plasma. α2M interacts and captures virtually any proteinase, often referred to as a panprotease inhibitor. In the brain of Alzheimer's disease (AD) patients, α2M also has been localized to diffuse amyloid plaques, supporting an important role for α2M in AD etiopathology.
Expand 1 Items
Anti-GJA1 Rabbit Polyclonal Antibody
Supplier: AbFrontier
Connexin 43(Cx43) is a widely expressed gap junction protein that
mediates communication between many cell types. Gap junctions are
implicated in tissue homeostasis and control of cell proliferation and
differentiation. Connexin 43 is predominantly localized at the sarcolemma,
where six connexins assemble into a so-called connexon or hemichannel.
Clusters of these channels assemble to make gap junctions. Cx43 is a
target protein of several kinases, among them PKA, PKC, PKG, MAPK,
and casein kinase, but also for protein phosphatases. The
phosphorylation of Cx43 at Ser368 by PKC induces a closure of
Hemichannels. Src can phosphorylate Cx43 to alter gap junction
communication.
Expand 1 Items
Anti-PPP2R1A/B Mouse Monoclonal Antibody [clone: 20G6]
Supplier: AbFrontier
Protein Phosphatase 2A (PP2A) is a ubiquitous and conserved Serine/Threonine phosphatase and accounts for a large fraction of phosphatase activity in eukaryotic cells. PP2A plays an important role in cell cycle regulation, cell growth control, development, regulation of various signal transduction pathways, and cell mobility.
PP2A comprises A and B subunits which are regulatory and a catalytic C subunit. When the PP2A catalytic C subunit (36 kDa) associates with the regulatory A (65 kDa, PR65) and B subunits (PR55, PR56, PR72, PR93 etc), wide variety of heterotrimeric holoenzymes are produced with distinct functions and characteristics. The different association of the subunits give PP2A large regulatory flexibility and differential substrate specificity. The A subunit exists as two isoforms ( α and β ) as does the C subunit, whereas the B subunits fall into three families designated B, B' (also called B56), and B''. The A subunit is the scaffold required for the formation of the heterotrimeric complex and the binding of A subunit alters the enzymatic activity of the catalytic subunit, even if the B subunit is absent.
Expand 1 Items
Anti-GLUL Rabbit Polyclonal Antibody
Supplier: AbFrontier
Glutamine Synthetase(GS) catalyzes the conversion of ammonia and glutamate to glutamine. This reaction consumes a molecule of ATP:
Glutamate + NH4+ + ATP
Glutamine + ADP + Pi
GS is found in astrocytes as an octamer of identical 45kDa subunits. Most well known function of GS is the detoxification of brain ammonia. It also has an important role in controlling metabolic regulations of neurotransmitter glutamate. Because of the multiple functions and importance of GS in cellular metabolism, both catalytic activities and synthesis are highly regulated. The activity of GS is controlled by adenylylation. Its activity is decreased in the cerebral cortex of brains affected by Alzheimer’s disease, particularly in the vicinity of senile plaques. It is also decreased under conditions of glucose deprivation. On the other hands, the level of expression of GS is increased during ischemia in vivo or hypoxia in culture.
Expand 1 Items
Anti-Serum Albumin Mouse Monoclonal Antibody [clone: 1G2]
Supplier: AbFrontier
Human serum albumin (HSA) is the most abundant protein in mammalian plasma and is generally considered to be a multifunctional transport protein. HSA is a signle-chain protein synthesized in and secreted from liver cells. HSA has significant antioxidant activity and may represent the major and predominant circulating antioxidant in plasma, which is known to be exposed to continuous oxidative stress. HSA protects human low density lipoproteins against copper-mediated oxidation and blood against hemolysis by free radicals. HSA which are exposed to glucose and have a relatively slow turnover rate are particularly susceptible to nonenzymatic glycosylation. Structural changes in glycosylated albumin lead to a reduction in affinity for fatty acid.
Expand 1 Items
Anti-CDK5 Rabbit Polyclonal Antibody
Supplier: AbFrontier
Cyclin-dependent kinase-5(CDK5) is a member of the cyclin-dependent kinase family of serine/threonine kinases. Its mRNA and protein are expressed in the kidneys, testes, and ovaries. And Its activity has been detected almost exclusively in brain extracts.
Similar to other Cdks, monomeric Cdk5 displays no enzymatic activity; however, Cdk5 is not activated by cyclins. Instead, Cdk5 activity requires association with one of two brain-specific regulatory subunits, called p35 and p39. These two activators regulate the spatial and temporal expression of active Cdk5, restricting its activity primarily to post-mitotic neurons.
Expand 1 Items
Anti-EGFR/ERBB2 Rabbit Polyclonal Antibody
Supplier: AbFrontier
The epidermal growth factor receptor (EGFR) is a transmembrane receptor tyrosine kinase of the ErbB (also known as HER) family in which four members have been identified: EGFR (ErbB1), HER2/Neu (ErbB2), HER3 (ErbB3), and HER4 (ErbB4). All four erbB receptors are composed of an extracellular ligand-binding region consisting of glycosylated domains, a transmembrane domain containing a single hydrophobic anchor sequence, an intracellular region containing the catalytic tyrosine kinase domain, and a carboxyl-terminal region containing several tyrosine residues that become phosphorylated after receptor activation.
The epidermal growth factor receptor (EGFR) signaling pathway is one of the most important pathways that regulate growth, survival, proliferation, and differentiation in mammalian cells. EGFR and other members of the erbB family form either homodimers or heterodimers upon ligand binding, resulting in conformational changes that allow activation of protein kinases and transphosphorylation of key tyrosine residues within the carboxyl-terminal domain. After the induction of tyrosine phosphorylation, some signaling pathways appear to start with the recognition of the C-terminal phosphotyrosines by appropriate adaptor or signaling molecules. The aberrant activation of the EGFR leads to enhanced proliferation and other tumor-promoting activities. Several mechanisms lead to aberrant receptor activation, including receptor overexpression, gene amplification, activating mutations, overexpression of receptor ligands, and/or loss of their negative regulatory mechanisms.
The epidermal growth factor receptor (EGFR) has been extensively investigated as a target for anti-neoplastic therapy. Anti-EGFR antibodies that interfere with ligand-dependent receptor activation have shown clinical activity in a variety of solid tumors.
Expand 1 Items
Anti-VIM Mouse Monoclonal Antibody [clone: 33C7]
Supplier: AbFrontier
Vimentin is a member of the intermediate filament family of proteins found in various non-epithelial cells, especially mesenchymal cells. Vimentin is responsible for maintaining cell shape, integrity of the cytoplasm, and stabilizing cytoskeletal interactions. Vimentin plays a significant role in supporting and anchoring the position of the organelles in the cytosol. Although most intermediate filaments are stable structures, vimentin also has a dynamic nature which is important when offering flexibility to the cell.
Two monomers which have central α-helical domains, capped on each end by non-helical domains twist around each other to form a coiled-coil dimer. Two dimers then form a tetramer, which, in turn, form a sheet by interacting with other tetramers.
There are some reports related to the biochemical function of intermediate filament network. The intracellular movement of LDL-derived cholesterol from the lysosome to the site of esterification is a vimentin-dependent process. A role for vimentin in mechanotransduction of shear stress has also been suggested. The mechanical stress of fluid shear on endothelial cells seems to trigger MAPK signaling pathways and stimulates proliferation.
Expand 1 Items
Anti-STAT2 Rabbit Polyclonal Antibody
Supplier: AbFrontier
STAT2 (Signal transducer and activator of transcription 2), 113kDa, is a member of the STAT family of cytoplasmic transcription factors. STAT members generally mediate cytokine, growth factor and hormone receptor signal transduction. STAT2 is a transcription factor critical to the signal transduction pathway of type I interferons (e.g. IFNα). STAT2 resides primarily in the cytoplasm and is tyrosine-phosphorylated after IFNα binds to cell surface receptors. In response to tyrosine phosphorylation STAT2 rapidly localizes to the nucleus and acquires the ability to bind specific DNA targets in association with two other proteins, STAT1 and IFN regulatory factor-9 (IRF-9). STAT2 is phosphorylated at Y689 by receptor-associated Janus kinasses (JAKs) leading to STAT2 dimerization and subsequent translocation to the nucleus to activate gene transcription.
Expand 1 Items
Anti-RIPK2 Mouse Monoclonal Antibody [clone: AF28D3]
Supplier: AbFrontier
The RIP(receptor-interacting protein) family of serine/Threonine kinases(RIP-1,2,3,4,5,6,7) are crucial regulators of cell survival and cell death that can trigger pro-survival, inflammatory and immune responses via the activation of transcription factors(NF-kB and AP-1) and death-inducing programs.
RIP2(also known as RICK, CARDIAK, CCK and Ripk2) transduces signals from receptors of both immune responses. RIP2 carries a CARD at its C-terminal, which is essential for NF-kB activation. RIP2 is a critical downstream mediator of Nod1 and Nod2 signaling. Overexpression of RIP2 results in the activation of, in addition to NF-kB, the MAPKs JNK and ERK2, requiring its kinase activity to activate ERK2, but not JNK.
Expand 1 Items
Anti-HSPB1 Rabbit Polyclonal Antibody
Supplier: AbFrontier
Heat shock proteins are ubiquitous proteins and have been characterized as cytoprotective molecular chaperones. The typical function of a chaperone is to assist a protein to attain its functional conformation to prevent non-functional aggregation of misfolded proteins. The principal HSP families are HSP90, HSP70, HSP60 and the small HSPs including HSP27, ubiquitin, α-crystallin, Hsp20 and others. The common functions of small Hsps are chaperone activity, thermotolerance, inhibition of apoptosis, regulation of cell development, and cell differentiation.
Hsp27 has a molecular weight of approximately 27 kDa, although it has been shown to form large aggregates of up to 800 kDa in the cytosol. Hsp27 is found in several types of human cells, including tumour cells. Hsp27 interferes with apoptosis through its ability to interact with and inhibit key components of the apoptotic signaling pathway, including the caspase activation complex. Overexpression of heat shock proteins can increase the tumorigenic potential of tumour cells. HSP27 also has been reported to be involved in development and progression of hormone-refractory prostate cancer.
Expand 1 Items
Anti-PTPRN Mouse Monoclonal Antibody [clone: AFT38]
Supplier: AbFrontier
IA-2 (insulinoma-associated protein 2, ICA512, PTPRN) is a member of the transmembrane protein tyrosine phosphatase (PTP) family located in secretory granules of neuroendocrine cells. The IA-2 protein is 979 amino acids in length and consists of a luminal domain, transmembrane domain, and cytoplasmic domain. Although a member of the PTP family, IA-2 lacks phosphatase activity with known substrates due to amino acid substitutions at critical sites in its PTP domain. Two paralog RPTPs, IA-2 and IA-2β were identified as major autoantigens in type-1 diabetes mellitus. On granule exocytosis, the IA-2 cytoplasmic domain is cleaved and the resulting cytosolic fragment moves into the nucleus where it enhances the levels of phosphorylated STAT5 and STAT3, thereby inducing insulin gene transcription and granule biogenesis. IA-2 signaling enhances pancreatic β–cell proliferation by regulating cyclins D through STATs.
Expand 1 Items
Anti-PTK2 Rabbit Polyclonal Antibody
Supplier: AbFrontier
Focal adhesion kinase subfamily consists of the non-receptor proline-rich protein tyrosine kinases (PTKs). Two members of the family are focal adhesion kinase (FAK) and proline-rich tyrosine kinase 2 (PYK2). These two kinases have molecular mass between 110-125 kDa and are closely related in their structure. The presence of two proline-rich motifs within the C-terminal domains is conserved.
FAK is a nonreceptor and nonmembrane associated PTK which does not contain Src homology 2 (SH2) or SH3 protein interaction domains. The centrally located kinase domain of FAK is flanked by large N- and C-terminal noncatalytic domains.
FAK links integrin receptors to intracellular signaling pathways that are important for cell growth, survival, and migration. Integrin receptor engagement with ligands such as fibronectin can stimulate FAK autophosphorylation which enables FAK to function within a network of integrin-stimulated signaling pathways leading to the activation of targets such as the ERK and JNK/mitogen-activated protein kinase pathways. Recent study reveals that FAK is essential for angiogenesis in the embryo, functions in heart development and modulates the response of cardiomyocytes to pressure overload in adult mice.
Expand 1 Items
Anti-RPS6KA4 Rabbit Polyclonal Antibody
Supplier: AbFrontier
Mitogen- and stress-activated protein kinases (MSK2) is nuclear kinase that act downstream of mitogen-activated protein/extracellular signal-regulated kinase pathways. It contains two kinase domains in the N-terminal and C-terminal region, respectively. MSK2 is activated in response to mitogenic stimuli via Erk1/2MAPK pathway and also by stress stimuli via p38MAPK pathway. Signals from mitogens and cellular stresses are involved in many functions including cell proliferation, differentiation, and survival through the phosphorylation of cyclic AMP response element-binding protein (CREB) at Ser133 which is catalyzed by MSK2. Recently, MSK2 has been shown to be required for stress-induced phosphorylation of histone H3-Ser and transcriptional activation of several immediate early genes.
Expand 1 Items
Anti-ACTB Rabbit Polyclonal Antibody
Supplier: AbFrontier
Anti-ACTB Rabbit Polyclonal Antibody
Expand 2 Items
Anti-CDK5 Mouse Monoclonal Antibody [clone: 8A1]
Supplier: AbFrontier
Cyclin-dependent kinase-5 (CDK5) is a member of the cyclin-dependent kinase family of serine/threonine kinases. Its mRNA and protein are expressed in kidney, testes, and ovary. And Its activity is detected almost exclusively in brain extracts.
Similar to other Cdks, monomeric Cdk5 displays no enzymatic activity, but Cdk5 is not activated by cyclins. Instead, Cdk5 activity requires association with one of two brain-specific regulatory subunits called p35 and p39. The two activators regulate the spatial and temporal expression of active Cdk5 to restrict its activity primarily to post-mitotic neurons.
Expand 1 Items
Anti-CSPS Rabbit Polyclonal Antibody
Supplier: AbFrontier
The human Catecholamine-Sulfating Phenol Sulfotransferase (CSPS) is the only sulfotransferase that catalyses the sulfation of catecholamins, in particular the neurotransmitter dopamine, with high activity. CSPS is required for stimulation by Mn2+ of the sulfating activity and expressed in the human intestine, brain, platelet and other tissues. In the brain it may play a role in regulating the levels of dopamine. It also serves as a detoxifying function in the intestine, where it may detoxify potentially lethal dietary monoamines.
Expand 1 Items
Anti-C6 Mouse Monoclonal Antibody [clone: 13H5]
Supplier: AbFrontier
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.
Human complement factor C6 is one of five components (C5b, C6, C7, C8, and C9) that interact to form the cytolytic membrane attack complex (MAC) which is the cytolytic end product of the complement cascade. MAC is typically formed on the surface of intruding pathogenic bacterial as a result of the activation of the complement system, and it is one of the ultimate weapons of the immune system.
The sixth component of complement, C6, is a 913 amino acid single polypeptide chain serum glycoprotein. Homology study suggests that C6 could contain two domains, an amino-terminal region that is related to complement C8 and C9, and a carboxyl-terminal region that has partial homology to the complement regulatory proteins factor H and factor I.
Genetic deficiencies of terminal complement components lead to markedly increased susceptibility to only one particular Gram-negative genus, the Neisseria. The susceptibility is attributable to the major role played by complement-mediated killing in host defense against the pathogen.
Expand 1 Items
Anti-AFP Mouse Monoclonal Antibody [clone: 8H2]
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.
Expand 1 Items
Anti-14-3-3 beta Mouse Monoclonal Antibody [clone: 60C10]
Supplier: AbFrontier
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(β, γ, ε, η, ζ, σ and τ/θ) 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.
Expand 1 Items
Anti-ATRN Mouse Monoclonal Antibody [clone: 9H8]
Supplier: AbFrontier
Attractin is a serum glycoprotein of 175 kDa and found in both membrane-bound and secreted forms as a result of alternative splicing. Both the secreted and membrane-bound forms of attractin may be involved in the development and maintenance of the central nervous system. Membrane-bound attractin is a co-receptor for Agouti, antagonist of melanocortin-1 receptor. Secreted attractin, expressed by activated T lymphocytes and modulates interactions between T cells and monocytes/macrophages, was examined as a potential marker of immune activity. Attractin may be a component of a pathway for regulated protein turnover that also involves mahogunin, a wide-expressed E3 ubiquitin ligase found at particularly high levels in the brain. Attractin was considered as an extracellular target amenable for the development of obesity-regulating drugs, also.
Expand 1 Items
Anti-IRS4 Rabbit Polyclonal Antibody
Supplier: AbFrontier
Insulin receptor substrate (IRS) proteins play a central role in maintaining basic cellular functions such as growth and metabolism through insulin/insulin like growth factor (IGF) signaling. Four members (IRS-1, IRS-2, IRS-3, IRS-4) of this family have been identified which differ in their subcellular distribution and interaction with SH2 domain proteins. After phosphorylation by activated receptors, these intracellular signaling molecules recruit various downstream effector pathways including phosphatidylinositol 3-kinase, tyrosine protein phosphatase SHPTP-2, and several smaller adapter molecules such as the growth factor receptor-binding protein Grb-2.
IRS-1, the best characterized IRS protein, has eighteen potential tyrosine phosphorylation sites which directly bind to SH2 domains in downstrem proteins. IRS-1 consists of amino terminal containing pleckstrin homology (PH) domain followed by a phosphotyrosine-binding (PTB) domain which binds to IR and IGFR, and carboxy terminal containing multiple tyrosine and serine residues which become docking sites for proteins that have PTB domain such as SH2 domain.
IRS-4 is the last identified member of the IRS family. Cloning of human IRS-4 revealed a predicted protein of similar length to both IRS-1 and IRS-2and showed only 27% and 29% identity with IRS-1 and IRS-2, respectively. In contrast, IRS-4 exhibits higher degree of homology in the PH domain (43 to 50 %) and the PTB domain (43 to 66%) with the corresponding domains in IRS-1, IRS-2 and IRS-3.
IRSs are also thought to be able to induce malignant transformation. IRS-1 has been shown to be constitutively active in breast cancer.
Expand 1 Items
Anti-MTOR Mouse Monoclonal Antibody [clone: 53E11]
Supplier: AbFrontier
Mammalian target of rapamycin (mTOR), a serine/threonine kinase involved in diverse cellular processes, including protein translation, mRNA turnover, and protein stability, mediates, at least in part, some of the biological actions of Akt. As a Kinase subunit of both mTORC1(complex1) and mTORC2(complex2), mTOR regulates cell growth and survival in response to nutrient and hormonal signals. mTORC1 is activated in response to growth factors or amino-acids. Activated mTORC1 up-regulates protein synthesis by phosphorylating key regulators of mRNA translation and ribosome synthesis. mTORC1 phosphorylates EIF4EBP1 and releases it from inhibiting the elongation initiation factor 4E (eiF4E). mTORC2 seems to function upstream of Rho GTPases to regulate the actin cytoskeleton, probably by activating one or more Rho-type guanine nucleotide exchange factors. mTORC2 promotes the serum-induced formation of stress-fibers or F-actin. mTORC2 plays a critical role in AKT1 'Ser-473' phosphorylation.
Expand 1 Items
Anti-C4B Mouse Monoclonal Antibody [clone: 35A12]
Supplier: AbFrontier
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.
Expand 1 Items
Anti-PDGFRB Rabbit Polyclonal Antibody
Supplier: AbFrontier
Platelet-derived growth factors (PDGFs) have been implicated in the control of cell proliferation, survival and migration. The PDGF family of growth factors consists of five different disulphide-linked dimers built up of four different polypeptide chains encoded by four different genes. Theses isoforms, PDGF-AA, PDGF-AB, PDGF-BB, PDGF-CC and PDGF-DD, act via two receptor tyrosine kinases, PDGF receptors α and β. Thus far, gene-targeting experiments have been attempted to create knockout mice deficient for PDGFR-α or PDGFR-β. Those mice, however, died either at the embryonic stage or several days after birth. Platelet-derived growth factor receptors, PDGFR-α and PDGFR-β, have five extracellular immunoglobulin-like domains and an intracellular tyrosine kinase domain. Upon binding a PDGF, the receptors form homo- and heterodimers. Dimerization of the receptors juxtaposes the intracellular part of the receptors, which allow phosphorylation in trans between the two receptors in the complex. These autophosphorylation provide docking sites for downstream signal transduction molecules. More than 10 different SH2–domain-containing molecules have been shown to bind to different autophosphorylation sites in the PDGF α- and β-receptors. There are signal transduction molecules with enzymatic activity, such as PI3-kinase, PLC-γ, Src, SHP-2, GAP, as well as adaptor molecules such as Grb2, Shc, Nck, Grb7 and Crk, and Stats. Each of the different partners recruited by the activated receptor initiates different signaling pathways, making possible a great variety of cellular response.
Expand 1 Items
Anti-PLCG Mouse Monoclonal Antibody [clone: 2B1]
Supplier: AbFrontier
The mammalian Phospholipase C(PLC) family has two closely related proteins, PLC1 and PLC2. The PLC isozymes have the core structure domains and a unique array of domains containing an additional PH domain, two SH2 domains and one SH3 domain. In response to extracellular stimuli, such as hormones and growth factors, receptor tyrosine kinases (RTKs) phosphorylate and activate PLC. Activated PLC catalyzes hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP2) to produce the metabolic second messenger molecules inositol 1,4,5-triphosphate (IP3) and diacylglycerol (DAG).
Expand 1 Items
Anti-MSRA Mouse Monoclonal Antibody [clone: 5B5]
Supplier: AbFrontier
Methionine sulfoxide reductase (MsrA) reduces methionine sulfoxide (MetO) residues in proteins and free MetO to Methionine (Met). The catalytic activity of MsrA is dependent of bound metal and cofactors but it requires reducing equivalents from either DTT or a thioredoxin-regenerating system. MsrA plays an essential role in protecting cells against oxidative damage. The substrates of MsrA include calmodulin, HIV protease and 1-proteinase-inhibitor (1-3). Recent studies indicate that there is a connection between MsrA and Alzheimer’s disease in mammals (4).