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Members of the Interferon regulatory factor (IRF) family regulate gene expression critical to immune response, hemopoiesis, and proliferation. IRF-3 is a member of the IRF family, and is distinct from other family members. Its transcriptional activity is regulated solely by posttranslational modifications. It plays a crucial role in activation of innate immunity and inflammation in response to viral infection. IRF-3 mediates interferon-stimulated response element (isre) promoter activation. Functions as a molecular switch for antiviral activity. Dsrna generated during the course of an viral infection leads to IRF3 phosphorylation on the c-terminal serine/threonine cluster. This induces a conformational change, leading to its dimerization, nuclear localization and association with creb binding protein (crebbp) to form dsrna-activated factor 1 (draf1), a complex which activates the transcription of genes under the control of isre. The complex binds to the ie and prdiii regions on the ifn

Transferrin is the iron-transport protein of vertebrate serum and donates iron to cells through interaction with a specific membrane receptor, CD71. Transferrin appears to be indispensable for most cells growing in tissue culture.
It is referred to frequently as a growth factor because, in analogy to other growth factor-receptor interactions, proliferating cells express high numbers of transferrin receptors, and the binding of transferrin to their receptors is needed for cells to initiate and maintain their DNA synthesis. Apart from its role as an iron transport protein transferrin acts as a cytokine and has functions that may not be related to its iron-carrying capacity.
Bovine Transferrin is a crucial component for the cultivation of mammalian cells in- vitro. Bovine Transferrin is Critical for long-term cells growth in-vitro. Bovine Transferrin is used as detoxificant in media by binding contaminating metal ions. Bovine Transferrin is often used as a nutrient in fermentation media for recombinant protein and biopharmaceutical production. Additional common uses of Bovine Transferrin are Molecular weight, Affinity purification of anti-human transferrin antibodies and also as receptor mediated transfection of molecules such as DNA, into cells.

Glia Maturation Factor-Beta (GMF-Beta) is a 17 kDa protein nerve gorwth factor identified as a growth and differentiation factor in the vertebrate brain.

Glia Maturation Factor-Beta stimulates differentiation of normal neurons as well as glial cells. GMFB inhibits the proliferation of the N-18 neuroblastoma line and the C6 glioma line while promoting their phenotypic expression.
GMF-beta inhances the phenotypic expression of glia & neurons thus inhibits the proliferation of their respective tumors when added to cell culture. Although astrocytes produce GMF-b and stores it inside the cells, they don’t secrete the GMF-B into the cultured medium. Cell- surface GMFb acts on the target cells at close range when cells are in direct contact. GMF-Beta is produced by thymic epithelial cells and plays an important role in T cell development in favor of CD4+ T cells.
GMF-Beta is a brain-specific protein which belongs to the actin-binding proteins (ADF) family. GMF-beta appears to play a role in the differentiation, maintenance, and regeneration of the nervous system. It also supports the progression of certain auto-immune diseases, possibly through its ability to induce the production and secretion of various pro-inflammatory cytokines.

Alpha 1-microglobulin (A1M) is a lipocalin superfamily member (kernal lipocalins). A1M is a low molecular weight protein component of plasma. A1M is distributed in plasma and extravascular compartments of all organs. Alpha-1 Microglobulin is found in mammals, birds, amphibians and fish. The primary sites of A1M synthesis are the liver and the kidney. Around the opening of the lipocalin pocket three lysyl residues are situated; those residues carry yellow-brown modification derived from the binding and degradation of heme and kynurenin (a tryptophan metabolite). A1-Microglobulin’s reductase and dehydrogenase have broad biological substrate specificity properties due to its’ free cysteine side-chain which is located in a flexible loop. Alpha-1-microglobulin is glycosylated by three separate carbohydrate chains: two complex carbohydrates which are N-linked to asparagines at residues 17 and 96, and the other simple carbohydrate which is O-linked to threonine at position 5. The carbohydrates comprise 22% of the total molecular mass of the protein. The glycosylation varies between species.
A1M exists in two forms- a free form and complexed to other macromolecules: in humans- complexed to immunoglobulin A (IgA), in rat- complexed to alpha-1-inhibitor-3. Free A1M is exceptionally heterogeneous in charge (therefore also known as protein HC), and is found tightly linked to a chromophore. The free Alpha-1-microglobulin is a monomeric protein composed of one 188 residue polypeptide and contains three cysteines, two of which (residues 75 and 173) form a conserved intra-molecular disulphide link. The chromophoric group is covalently bound to the free cysteine residue at position 34. A1M binds retinol as a major ligand, but this is probably distinct from its covalent chromophore.
Half of all human plasma A1M (approximately 0.03mg/ml) forms a 1:1 complex with about 5% of plasma immunoglobulin A. The resulting macromolecular complexes’ molecular weight is 200000, and a plasma concentration of 0.3mg/ml. The complex can exhibit both antibody activity and affect many of the biological actions of free Alpha-1-microglobulin.
Alpha-1-microglobulin was first discovered in pathological human urine.
It was suggested that A1M might be involved in tissue defense against reactive oxygen species, oxidation by heme and kynurenin. Evidence also suggests that A1M functions in the regulation of the immune system. Other functions include inhibition of stimulation of cultured lymphocytes by protein antigens; induction of cell division of lymphocytes, a mitogenic effect that can either be enhanced or inhibited by the action of other plasma components; inhibition of neutrophil granulocyte migration in vitro; and inhibition of chemotaxis.

Plasma protease C1 inhibitor (SERPING1) is a part of the serpin superfamily of serine protease inhibitors. SERPING1 takes part in regulating activation of both the complement and contact systems. That isdue to the fact that SERPING1 regulates the activation of complement factor C1 in addition to the activity of activated C1 by coupling with the active catalytic site at the light chains of C1r and C1s. Lack of SERPING1 results in hereditary angioedema, which is characterized by recurrent episodes of localized angioedema of the skin, gastrointestinal mucosa or upper respiratory mucosa.

The epidermal growth factor receptor (EGF R) subfamily of receptor tyrosine kinases comprises four members: EGF R (also known as HER1, ErbB1 or ErbB), ErbB2 (Neu, HER-2), ErbB3 (HER-3), and ErbB4 (HER-4). All family members are type I transmembrane glycoprotein that has an extracellular domain which contains two cysteine-rich domains separated by a spacer region that is involved in ligand-binding, and a cytoplasmic domain which has a membrane-proximal tyrosine kinase domain and a C-terminal tail with multiple tyrosine autophosphorylation sites. The human EGF R gene encodes a 1210 amino acid (aa) residue precursor with a 24 aa putative signal peptide, a 621 aa extracellular domain, a 23 aa transmembrane domain, and a 542 aa cytoplasmic domain. EGF R has been shown to bind a subset of the EGF family ligands, including EGF, amphiregulin, TGF-a , betacellulin, epiregulin, heparin-binding EGF and neuregulin-2 in the absence of a co-receptor. Ligand binding induces EGF R homodimerization as well as heterdimerization with ErbB2, resulting in kinase activation, tyrosine phosphorylation and cell signaling. EGF R can also be recruited to form heterodimers with the ligand-activated ErbB3 or ErbB4. EGF R signaling has been shown to regulate multiple biological functions including cell proliferation, differentiation, motility and apoptosis. In addition, EGF R signaling has also been shown to play a role in carcinogenesis.

AGXT is expressed only in the liver and its protein is localized mostly in the peroxisomes, where it is involved in glyoxylate detoxification. Mutations in the AGXT gene, some of which alter subcellular targetting, have been linked to type I primary hyperoxaluria.

ASF1 Anti-Silencing Function 1 Homolog B (ASF1B) belongs to the H3/H4 family of histone chaperone proteins and is similar to the anti-silencing function-1 protein in yeast. ASF1B is the substrate of the tousled-like kinase family of cell cycle-regulated kinases, and may have a crucial role in modulating the nucleosome structure of chromatin by guaranteeing a regular supply of histones at sites of nucleosome assembly. ASF1B cooperates with CAF-1 (chromatin assembly factor 1) to stimulate replication-dependent chromatin assembly. ASF1B is highly expressed in the testis and at lower levels in colon, small intestine and thymus. ASF1B is necessary for spermatogenesis.

Transforming growth factor betas (TGFBetas) mediate many cell-cell interactions that occur during embryonic development. Three TGFBetas have been identified in mammals. TGFBeta1, TGFBeta2 and TGFBeta3 are each synthesized as precursor proteins that are very similar in that each is cleaved to yield a 112 amino acid polypeptide that remains associated with the latent portion of the molecule. This antibody reacts with the precursor and mature form of TGFBeta2 and to a lesser extent TGFBeta3, but does not cross react with TGFBeta1.

The Trefoil Factor peptides (TFF1, TFF2 and TFF3) are stable secretory proteins expressed in the gastrointestinal tract (gastric mucosa), and are involved in intestinal mucosal defense and repair. TFF1 is an essential protein for normal differentiation of the antral and pyloric gastric mucosa and functions as a gastric-specific tumor suppressor gene. TFF1 is a stabilizer of the mucous gel overlying the gastrointestinal mucosa that provides a physical barrier against various noxious agents. TFF1 protects the mucosa from isults, stabilizes the mucus layer, & affects healing of the epithelium. TFF1 is commonly expressed in tumors. TFF1 is related with the cell membrane of MCF-7 cells. High levels of TFF1 and TFF2 are found in serum from inflammatory bowel disease.

RNH1 belongs to the proteinaceous cytoplasmic RNase inhibitors family which occur in many tissues and binds to both intracellular and extracellular RNases. In addition to control of intracellular RNases, the inhibitor may have a part in the regulation of angiogenin. The 50kDa RNH1 binds to ribonucleases and holds them in a latent form. Since neutral and alkaline ribonucleases possibly play a critical role in the turnover of RNA in eukaryotic cells, RNH1 may be vital for control of mRNA turnover; the interaction of eukaryotic cells with ribonuclease may be reversible in vivo.

Platelet factor-4 is a 70-amino acid protein that is released from the alpha-granules of activated platelets. Its major physiologic role appears to be neutralization of molecules on the endothelial surface of blood vessels, thereby inhibiting local antithrombin III activity and promoting coagulation. As a strong chemoattractant for neutrophils and fibroblasts, PF4 probably has a role in inflammation and wound repair. Oncostatin-A is a member of the CXC chemokine family. Furthermore it is used as an inhibitor in the angiogenesis during tumor therapy.

Epidermal growth factor receptor or EGFR or Erb-1 is a membranal protein that acts as a receptor for the extracellular EGF proteins family. This protein is a part of a family of receptors called ErbB family which are all tyrosine kinases receptors. Mutations in the gene of this receptors can cause cancer.

Serine/threonine-protein kinase 16 (STK16) is a membrane-associated protein kinase which phosphorylates on serine and threonine residues. STK16 is involved in secretory vesicle trafficking or intracellular signaling. Furthermore, the STK16 protein may have a role in regulating stromal-epithelial interactions which occur during ductal morphogenesis in the mammary gland. STK16 can autophosphorylate on Tyr residue; it is however unclear whether STK16 has tyrosine-protein kinase toward other proteins. STK16 may also be involved in TGF-beta signaling.

Proprotein Convertase Subtilisin/Kexin Type 1 Inhibitor (PCSK1N) takes part in the control of the neuroendocrine secretory pathway. PCSK1N inhibits prohormone convertase 1, which regulates the proteolytic cleavage of neuroendocrine peptide precursors. PCSK1Nslows down convertase-mediated processing of proopiomelanocortin and proenkephalin and also monitors the intracellular timing of PCSK1.

The 26S proteasome is a multicatalytic proteinase complex with a well ordered structure composed of two complexes- a 20S core and a 19S regulator. PSMD11 is a non-ATPase subunit of the 19S regulator. The 20S core is composed of four rings of 28 non-identical subunits; two rings are composed of 7 alpha subunits and two rings are composed of 7 beta subunits. The 19S regulator is composed of a base that contains six ATPase subunits and two non-ATPase subunits, and a lid that contains up to ten non-ATPase subunits. Proteasomes are spread throughout eukaryotic cells at a high concentration and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway. An indispensable function of a modified proteasome, the immunoproteasome, is the processing of class I MHC peptides.

BDNF promotes the survival of neuronal populations that are all located either in the central nervous system or directly connected to it. BDNF is a major regulator of synaptic transmission and plasticity at adult synapses in many regions of the cns. The versatility of BDNF is emphasized by its contribution to a range of adaptive neuronal responses including long-term potentiation (ltp), long-term depression (ltd), certain forms of short-term synaptic plasticity, as well as homeostatic regulation of intrinsic neuronal excitability.

NFATC1 is a component of the nuclear factor of activated T cells DNA-binding transcription complex. This complex consists of at least 2 components: a preexisting cytosolic component that translocates to the nucleus upon T cell receptor (TCR) stimulation, and an inducible nuclear component. Proteins belonging to this family of transcription factors play an essential role in inducible gene transcription during immune response. NFATC1 is an inducible nuclear component. NFATC1 functions as a major molecular target for the immunosuppressive drugs such as cyclosporin A. Different isoforms of NFATC1 may regulate inducible expression of different cytokine genes.

Connective Tissue Growth Factor belongs to the CCN family of proteins. The CCN family presently consists of six members in human also known as: Cyr61 (Cystein rich 61), CTGF (Connective Tissue Growth Factor), Nov (Nephroblastoma Overexpressed gene), WISP-1, 2 and 3 (Wnt-1 Induced Secreted Proteins). The CCN genes encode secreted proteins associated with the Extracellular Matrix (ECM) and cell membrane.
CCN proteins are matricellular proteins which are involved in the regulation of various cellular functions including: proliferation, differentiation, survival, adhesion and migration. They are expressed in derivatives of the three embryonic sheets and are implicated in the development of kidney, nervous system, muscle, bone marrow, cartilage and bone. During adulthood, they are implicated in wound healing, bone fracture repair, and pathologies such as: fibrosis, vascular ailments and tumorigenesis.
Full length secreted CCN proteins can show an antiproliferative activity, whereas truncated isoforms are likely to stimulate proliferation and behave as oncogenes.
The full length protein consists of four modulesModule I shares partial identity with the N-terminal part of the IGFBPs.
Module II includes a stretch of 70amino acid residues – which shares sequence identity with the Von Willebrand Factor Type C repeat (VWC).
Module III contains sequences sharing identity with the Thrombospondin type 1 repeat (TSP1) (WSXCSXXCG), which is thought to be implicated in the binding of sulfated glycoconjugates and to be important for cell adhesion.
Module IV, also designated CT, is encoded by exon5. It is the leasts conserved one of the four domains at the level of nucleotide sequence, but it appears to be critical for several of the biological functions attributed to the CCN proteins. Module IV resembles the CT domain of several extracellular protein including, Von Willebrand's factor and mucins. Sequence similarities to binding motifs are also found within this domain.
Proteolysis of the secreted full-length CCN proteins that has been reported in the case of CCN2 and CCN3 might result in the production of CCN-derived peptides with high affinity for ligands that full-length CNN proteins bind only poorly. Amino-truncated CCN2 isoforms were biologically active whereas no specific biological activity has been attributed to the truncated CCN3. Although the molecular processes underlying the production of these secreted isoforms is presently unknown, it is important to note that proteolysis occur at the same amino acid residues in both CCN2 and CCN3. An elevated expression of CCN2 has also been detected by Northern blotting in human invasive mammary ductal carcinomas, dermatofibromas, pyogenic granuloma, endothelial cells of angiolipomas and angioleiomyomas, and in pancreatic tumors. A study performed with chondrosarcomas representative of various histological grades established that CCN2 expression was closely correlated with increasing levels of malignancy.
In agreement with CCN2 playing a role in brain tumor angiogenesis, immunocytochemistry studies indicated that both glioblastoma tumor cells and proliferating endothelial cells stained positive for CCN2. In astrocytomas, CCN2 expression was particularly elevated in high grade tumors, with a marked effect of CCN2 on cell proliferation. Downregulation of CCN2 expression in these cells was associated with a growth arrest at the G1/S transition while over-expression of CCN2 induced a two-fold increase of the number of cells in the G1 phase. Gene profiling analysis allowed to identify a set of about 50 genes whose expression might account for the proliferative activity of CCN2 in these cells.
CCN2 was seen in a higher proportion of mononuclear cells of patients with acute lymphoblastic leukemia.

TNF-related apoptosis-inducing ligand (TRAIL) is a ligand molecule which induces apoptosis. It is a type II transmembrane protein with homology to other members of the tumor necrosis factor family.
In humans, the gene that encodes for TRAIL is located at chromosome 3q26. TRAIL binds to the death receptors, DR4 and DR5. The process of apoptosis is caspase-8-dependent. This protein preferentially induces apoptosis in transformed and tumor cells, but does not appear to kill normal cells although it is expressed at a significant level in most normal tissues.

TRAIL Receptor-4 Human Recombinant or TNFRSF10D, is part of the TNF-receptor superfamily. TNFRSF10D has atruncated cytoplasmic death domai , an extracellular TRAIL-binding domain and a transmembrane domain. The protein can prevent from TRAIL-mediated apoptosis on cells with TRAIL R1 and/or TRAIL R2.

Platelet factor-4 is a 70-amino acid protein that is released from the alpha-granules of activated platelets and binds with high affinity to heparin. Its major physiologic role appears to be neutralization of heparin-like molecules on the endothelial surface of blood vessels, thereby inhibiting local antithrombin III activity and promoting coagulation. As a strong chemoattractant for neutrophils and fibroblasts, PF4 probably has a role in inflammation and wound repair. Oncostatin-A is a member of the CXC chemokine family. Human PF4 is used for the proof of heparin-induced thrombocytopenia. Furthermore it is used as an inhibitor in the angiogenesis during tumor therapy.