| Description | Inquire | Protein Purity≥85% by SDS PAGEExtinction CoeffA280 nm = 0.631 at 1.0 mg/ml for pure C1qMolecular Weight400,000 Da (18 chains)General DescriptionRat C1q is purified from pooled normal rat serum. C1q is part of the C1 complex, which is the first complement component in the classical pathway of Protein Purity≥85% by SDS PAGEExtinction CoeffA280 nm = 0.631 at 1.0 mg/ml for pure C1qMolecular Weight400,000 Da (18 chains)General DescriptionRat C1q is purified from pooled normal rat serum. C1q is part of the C1 complex, which is the first complement component in the classical pathway of complement. The C1 complex is a non-covalent assembly of three different proteins (C1q, C1r, and C1s) bound together in a calcium-dependent complex. C1q has six extended arms with domains at the end of each arm that bind to the Fc domains of immunoglobulins such as IgG or IgM. When antibodies bind toantigens, forming immune complexes, they cluster allowing two or more of the six C1q arms to bind to the Fc domains of antibodies. Rat IgG2 is very efficient when compared to IgG1 in activating complement (Medgyesi, G.A et., al., 1981). This is in contrast to the human system in which IgG1 activates complement but not IgG2 (Redpath, S. et. al., 1998). The binding of multiple arms of C1q to immune complexes causes the two C1r proteins in the complex (protease zymogens) to auto-activate. The activated C1r proteases cleave and activate the two C1s protease zymogens in the complex. The activated C1s cleaves complement component C4 releasing C4a and initiating covalent attachment of C4b to the activating surface. Activated C1s also cleaves C2 and the larger fragment of C2 binds to the surface-attached C4b forming C4b,C2a, the C3/C5 convertase of the classical pathway.Rat IgG1 cannot activate complement whereas rat IgG2 does.Physical Characteristics & StructureThe apparent molecular weight of rat C1q as determined by gel filtration has been reported to be 400,000 by Veerhuis, R. et al., (1985) and is calculated to be 420,000 based on its amino acid sequence. Rat C1q is a high molecular weight complex of 18 polypeptide chains. Each of the six arms of rat C1q contains three chains, an A chain (~30,000 daltons), a B chain (~28,000 daltons) and a C chain (~26,000 daltons) as determined by SDS/polyacrylamide gel electrophoresis (Wing, M.G. et al., (1993)).FunctionThe biological functions of C1q are described above in the General Description and Physical Characteristics sections.ApplicationsRat C1q can be used to coat ELISA plates to capture and quantitate immune complexes in samples from rat models used for studying immune complex related diseases and conditions.GeneticsNCBI Gene ID numbers for rat C1q are: C1q A chain (298566), C1q B chain (29687), and C1q C chain (362634). The genes for C1q chains A, B and C are all located on chromosome 5. The UniprotKB primary accession numbers for rat C1q are: C1q A chain (P31720), C1q B chain (P31721), and C1q C chain (P31722).Precautions/Toxicity/HazardsThis protein is purified from animal plasma/serum and therefore precautions appropriate for handling any animal blood-derived product must be used.ReferencesMedgyesi, G.A et., Miklos, K., Kulics, J., Fust, G., and Gergely, J. Bazin, H. (1981). Classes and subclasses of rat antibodies: reaction with the antigen and interaction of the complex with the complement system. Immunology 43, 171-176.Redpath, S., Michaelsen, T., Sandlie, I. and Clark, M. R. (1998). Activation of complement by human IgG1 and human IgG3 antibodies against the human leucocyte antigen CD52. Immunology 93, 595–600.Veerhuis, R., Van Es, L.A. and Daha, M.R. (1985). In vivo degradation of rat C1q induced by intravenous injection of soluble IgG aggregates. Immunology 54, 801-810.Wing, M.G., Seilly, D. J., Bridgman, D.J. and Harrison, R.A. (1993). Rapid isolation and biochemical characterization of rat C1 and C1q. Molecular Immunology 30, 433-440... Read More | Purity:>95%, by SDS-PAGE visualized with Coomassie® Blue Staining.Description：Histones are a complex family of highly conserved basic proteins responsible for packaging chromosomal DNA into nucleosomes. Histone proteins exhibit two levels of diversity: 1. evolutionary diversity Purity:>95%, by SDS-PAGE visualized with Coomassie® Blue Staining.Description：Histones are a complex family of highly conserved basic proteins responsible for packaging chromosomal DNA into nucleosomes. Histone proteins exhibit two levels of diversity: 1. evolutionary diversity between species and 2. subtype diversity in a class(H1, H2A, H2B, H3 or H4) within a species. It has become more and more evident that histone modifications are key players in the regulation of chromatin states and dynamics as well as in gene expression. Therefore, histone modifications and the enzymatic machinery that set them are crucial regulators that can control cellular proliferation, differentiation, plasticity, and malignancy processes. However, extracellular histones are a double-edged sword because they also damage host tissue and may cause death. Histones bound to platelets, induced calcium influx, and recruited plasma adhesion proteins such as fibrinogen to induce platelet aggregation. Histone H2B proteins have been studied in a variety of species and are easily detected in most species. The reversible ubiquitylation of histone H2B has long been implicated in transcriptional activation and gene silencing. Phosphorylation of H2B serine 32 occurs in normal cycling and mitogen-stimulated cells. Notably, this phosphorylation is elevated in skin cancer cell lines and tissues compared with normal counterparts. HIST2H2BE is a member of the histone H2B family and generates two transcripts through the use of the conserved stem-loop termination motif, and the polyA addition motif... Read More | Purity> 97 % by SDS-PAGE and HPLC analyses.Additional sequence informationMature protein.FunctionPromotes neurite outgrowth and especially branching of neuritic processes in primary hippocampal and cortical cells | Purity:>95%, by SDS-PAGE visualized with Coomassie® Blue Staining. Description： 100B, previously called S100 beta, belongs to the S100 family within the EF-hand superfamily of Ca2+ binding proteins. S100 proteins contain two EF-hand motifs that differ in affinity, separated by a hingePurity:>95%, by SDS-PAGE visualized with Coomassie® Blue Staining. Description： 100B, previously called S100 beta, belongs to the S100 family within the EF-hand superfamily of Ca2+ binding proteins. S100 proteins contain two EF-hand motifs that differ in affinity, separated by a hinge region with a hydrophobic cleft that is exposed upon Ca2+ binding. S100B is a 91 amino acid (aa) protein, after removal of the initial methionine, and is found as homodimers of 10.4 kDa monomers. Human S100B shares 99%, 98%, 100%, 99% and 97% aa sequence identity with mouse, rat, rabbit, equine and bovine S100B, respectively. Within the S100 family, human S100B shows the highest aa identity (59%) with S100A1. S100B is expressed primarily by astrocytes and oligodendrocytes in the central nervous system, and by Schwann cells in the peripheral nervous system. Ca2+-bound S100B interacts in vitro with at least 20 cytoplasmic proteins, including several structural molecules such as tubulin and GFAP. It can inhibit the phosphorylation of these kinase substrates and others such as tau and neuromodulin. Astrocytes can secrete S100B, which then acts in a cytokine-like manner. Nanomolar concentrations of S100B are secreted constitutively, promote proliferation, and are neurotrophic and anti-apoptotic. Blood levels of S100B reflect extracellular concentrations within the nervous system, and are elevated in Down’s syndrome, Alzheimer’s disease and Tourette’s syndrome, metabolic stress, acute brain injury and brain tumors. Micromolar concentrations of S100B can be destructive and pro-apoptotic; they induce the expression of iNOS, COX-2, IL-1, IL‑6 and TNF-alpha by microglia, astrocytes or neurons. Most extracellular actions of S100B can be mediated by RAGE (receptor for advanced glycation end products), which is also a receptor for other S100 proteins... Read More |