| Description | IRE1α kinase-IN-1 is a highly selective IRE1α (ERN1) inhibitor, with an IC 50 of 77 nM. IRE1α kinase-IN-1 displays 100-fold selectivity for IRE1α over the IRE1β isoform. IRE1α kinase-IN-1 inhibits ER stress-induced IRE1α oligomerization and autophosphorylation, andIRE1α kinase-IN-1 is a highly selective IRE1α (ERN1) inhibitor, with an IC 50 of 77 nM. IRE1α kinase-IN-1 displays 100-fold selectivity for IRE1α over the IRE1β isoform. IRE1α kinase-IN-1 inhibits ER stress-induced IRE1α oligomerization and autophosphorylation, and also inhibits IRE1α RNase activity (IC 50 =80 nM).In VitroIRE1α kinase-IN-1 (compound 31) prevents endoplasmic reticulum stress-induced IRE1α oligomerization and phosphorylation, and inhibits endoribonuclease activity in human cells. IRE1α kinase-IN-1 and is very high selectivity with >70% inhibition of only 4/455 kinases. IRE1α kinase-IN-1 inhibits recombinant G547 IRE1α KEN domain pS274 autophosphorylation with an IC 50 of 160 nM. IRE1α kinase-IN-1 inhibits tunicamycin-induced GFP-IRE1α foci in HEK293 cells with an IC 50 of 0.74 µM. IRE1α kinase-IN-1 Inhibits ATP-site LanthaScreen tracer binding to recombinant dephosphorylated G547 IRE1α KEN with an IC 50 of 0.27 µM. IRE1α kinase-IN-1 inhibits both tunicamycin- and thapsigargin-induced IRE1α-dependent splicing of XBP1 luciferase fusion mRNA in HEK293 cells with IC 50 s ranging 0.68-1.63 µM. IRE1α kinase-IN-1 (0-20 µM) inhibits IRE1α-dependent XBP1s mRNA expression in H929 cells.IRE1α kinase-IN-1 (0-20 µM) dose-dependently inhibits tunicamycin-induced expression of XBP1s in NCI-H929 cells. MCE has not independently confirmed the accuracy of these methods. They are for reference only... Read More | C1q separated from C1r and C1s and from other stabilizing proteins tends to aggregate easily. Because it was isolated and studied in numerous research laboratories, many buffers have been used to stabilize concentrated C1q and prevent aggregation. About half of the scientists prefer high salt and C1q separated from C1r and C1s and from other stabilizing proteins tends to aggregate easily. Because it was isolated and studied in numerous research laboratories, many buffers have been used to stabilize concentrated C1q and prevent aggregation. About half of the scientists prefer high salt and the other prefer 40% glycerol in the storage buffer.C1q is purified from pooled normal human plasma. C1q is part of the C1 complex and this complex is the first complement component in the cascade referred to as the classical pathway of complement. C1 is actually 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. When antibodies bind to antigens forming immune complexes they cluster allowing two or more of its six arms of C1q to bind to the Fc domains of antibodies such as IgG or IgM. The binding of multiple arms to immune complexes causes the two C1r proteins in the complex (protease zymogens) to auto-activate producing two C1r proteases that cleave and activate the two C1s protease zymogens in the complex. 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 which is the C3/C5 convertase of the classical pathway.Extinction Coeff.A₂₈₀ nm = 0.68 at 1.0 mg/ml for pure C1q Molecular weight:410,000 Da (18 chains)Preservative:None, 0.22 µm filtered.Source:Normal human serum (shown by certified tests to be negative for HBsAg, HTLV-I/II, STS, and for antibodies to HCV, HIV-1 and HIV-II).Physical Characteristics & StructureC1q is a high molecular weight complex of 18 polypeptide chains. Each of the six arms of C1q contains three chains, an A chain (26,000 daltons), a B chain (25,000 daltons) and a C chain (24,000 daltons). The three chains are coiled into a collagen-like triple helix over approximately half their length. Half of this collagen region forms a central core where all 18 chains come together. The chains are joined in this core by disulfides in the pattern A-B and C-C. There is a bend in the center of the collagen region allowing the arms to extend away from each other. Globular heads at the far ends of the collagen arms possess binding sites for Fc domains of immunoglobulins. C1 complex is composed of one C1q molecule (410,000 daltons), two C1r molecules (92,000 daltons) and two C1s molecules (86,000 daltons). The complex is stable in the presence of calcium, but easily dissociates if calcium is removed. When C1 is activated the C1r and C1s subunits are each cleaved into two chain molecules due to proteolytic activation. Thus, the SDS gel pattern of C1 is very complex. Function The biological functions of C1q are described above in the General Description and Physical Characteristics sections. C1q functional activity may be assayed using C1q-depleted serum and EA cells. These assays are extremely sensitive to C1q typically yielding 50% lysis with less than 2 ng C1q in assays measuring the lysis of EA cells. AssaysThe unit of classical pathway activity is the CH50. A similar unit, the C1qH50, is used to quantitate the activity of C1q. A C1qH50 unit is the amount of functional C1q needed to lyse 50% of 3×10^7 EA cells (antibody-sensitized sheep erythrocytes) when that amount of C1q is incubated with 5-20 µL of C1q-Dpl in GVB++ in a total volume of 500 µL for 30 min at 37℃. This amount of C1q indicates the sensitivity of the assay for C1q which is typically about 1 ng C1q with 10 µL C1q-Dpl. See the Certificate of Analysis for lot specific values.ApplicationsC1q is used to coat ELISA plates to capture and quantitate immune complexes in clinical samples. A number of commercial companies sell diagnostic kits for immune complex detection and quantitation. These kits are based on the ability of C1q to bind well to immune complexes, but to not bind significantly to monomeric immunoglobulins. GeneticsThe EMBL/Genbank cDNA accession numbers are: C1q A chain (P02745), C1q B chain (P02746), and C1q C chain (P02747). The genes for C1q chains A, B and C are all located on chromosome 1p in the order A-C-B. DeficienciesDeficiencies of each of the three components of C1 have been found. Patients lacking C1q generally have immune-complex-mediated renal disease and skin lesions. Like all patients lacking early classical pathway components C1q deficient individuals are prone to systemic lupus erythrematosis (SLE) and recurrent pyogenic infections. They lack classical pathway function and may or may not exhibit C1q antigen in blood.DiseasesSee section titled Deficiencies above. Precautions/Toxicity/HazardsThis protein is purified from human serum and therefore precautions appropriate for handling any blood-derived product must be used even though the source was shown by certified tests to be negative for HBsAg, HTLV-I/II, STS, and for antibodies to HCV, HIV-1 and HIV-II... Read More | Inquire | Purity:>95%, by SDS-PAGE visualized with Coomassie® Blue Staining.Description：CD4, also known as L3T4, T4, and W3/25, is an approximately 55 kDa type I transmembrane glycoprotein that is expressed predominantly on thymocytes and a subset of mature T lymphocytes. It is a standard Purity:>95%, by SDS-PAGE visualized with Coomassie® Blue Staining.Description：CD4, also known as L3T4, T4, and W3/25, is an approximately 55 kDa type I transmembrane glycoprotein that is expressed predominantly on thymocytes and a subset of mature T lymphocytes. It is a standard phenotype marker for the identification of T cell populations. Mature feline CD4 consists of a 388 amino acid (aa) extracellular region containing four immunoglobulin-like domains, a 22 aa transmembrane segment, and a 40 aa cytoplasmic domain. Within the ECD, feline CD4 shares 70%, 58%, 50%, and 48% aa sequence identity with canine, human, mouse and rat CD4, respectively. CD4 is expressed along with CD8 on double positive T cells during their development in the thymus. Either CD4 or CD8 expression is then lost, giving rise to single positive (SP) CD4+ or CD8+ mature T cells. CD4+ SP cells, also known as T helper cells, further differentiate into multiple subsets of CD4+ cells including Th1, Th2, Th17, Tfh, and Treg cells which regulate humoral and cellular immunity. CD4 is reexpressed on circulating CD8+ T cells upon activation and contributes to their cytotoxic effector activity. In human, CD4 is additionally expressed on macrophages, neutrophils, monocytes, NK cells, and neurons and glial cells in the brain. Similar CD4 distribution between species cannot be assumed as demonstrated by its presence on macrophages in human and rat but not in mouse. CD4 binds directly to MHC class II molecules on antigen presenting cells. This interaction contributes to the formation of the immunological synapse which is focused around the TCR-MHC class II-antigenic peptide interaction. Palmitoylation of two cysteine residues in the cytoplasmic tail of CD4 promotes the localization of CD4 in lipid rafts and its ability to augment TCR signaling via activation of the tyrosine kinase Lck. CD4 also functions as a chemotactic receptor for IL-16 and, in human, as a coreceptor for the gp120 surface glycoprotein of HIV-1... Read More | Purity:>90%, by SDS-PAGE visualized with Coomassie® Blue Staining.Description：p53 is well known for its key role as a tumor suppressor protein. It is 393 amino acids (aa) in length with a predicted molecular weight of 44 kDa. It belongs to the p53 family that also includes p63 and p73Purity:>90%, by SDS-PAGE visualized with Coomassie® Blue Staining.Description：p53 is well known for its key role as a tumor suppressor protein. It is 393 amino acids (aa) in length with a predicted molecular weight of 44 kDa. It belongs to the p53 family that also includes p63 and p73. Structurally, p53 is characterized by an N-terminal transactivation domain, central DNA-binding and oligomerization domains, and a C-terminal regulatory domain. It is thought to exist as a homotetramer, and it exhibits approximately 72% and 76% aa identity with its mouse and rat orthologs, respectively. Mutations in the p53 gene are one of the most frequent genomic events accompanying oncogenic transformation. p53 responds to signals such as DNA damage or cell stress primarily through its actions as a transcription factor. Among its gene targets are a range factors that promote DNA repair mechanisms or apoptosis, including cell cycle regulatory proteins and members the Bcl-2 family. Because of its critical role in genomic homeostasis, p53 activities are tightly regulated by a network of protein-protein interactions, microRNAs, and a range of post-translational modifications, including phosphorylation, acetylation, methylation, and ubiquitination. A widely studied regulator is Murine Double Minute 2 (MDM2). MDM2 is known to suppress p53 activity through direct binding or through its actions as a Ubiquitin ligase (E3) that catalyzes p53 ubiquitination and proteasome-mediated degradation... Read More |