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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.

Entry of HSV into the host cell involves interactions of several viral glycoproteins with cell surface receptors. The virus particle is covered by an envelope which, when bound to specific receptors on the cell surface, will fuse with the cell membrane and create an opening, or pore, through which the virus enters the host cell. The sequential stages of HSV entry are analagous to those of other viruses. At first, complementary receptors on the virus and cell surface bring the two membranes into proximity. In an intermediate state, the two membranes begin to merge, forming a hemifusion state. Finally, a stable entry pore is formed through which the viral envelope contents are introduced to the host cell.

A fusion tag called FLAG consists of eight amino acids (AspTyrLysAspAspAspAspLys) including an enterokinase-cleavage site. FLAG is specifically designed for immunoaffinity chromatography. It allows elution under non-denaturing conditions. Several antibodies against this peptide have been developed. One antibody. denoted as M1. binds the peptide in the presence of bivalent metal cations. preferably Ca(+). Elution is effected by chelating agents. Another strategy is competitive elution with excess of free Flag Peptide.
The FLAG peptide purifies and detects recombinant fusion proteins. FLAG peptide is useful in Western blotting, immunocytochemistry, immunoprecipitation, flow cytometry, protein purification, and in the study of protein-protein interactions, cell ultrastructure, and protein localization. Flag peptide is a hydrophilic tag which significantly improves the detection and purification of recombinant fusion proteins.

E-Selectin belongs to a family of divalent cation-dependent carbohydrate-binding glycoproteins or adhesion molecules. CD62E is expressed on the surface of endothelial cells and mediates the interaction of leukocytes and platelets with endothelial cells during an inflammatory response. CD62E is found in cytokine-stimulated endothelial cells and is accountable for the accumulation of blood leukocytes at sites of inflammation by mediating the adhesion of cells to the vascular lining. It demonstrates structural features such as the existence of lectin- and EGF-like domains followed by short consensus repeat (SCR) domains that contain 6 conserved cysteine residues. E-Selectin participates in the interaction between leukocytes and the endothelium and appears to be involved in the pathogenesis of atherosclerosis.

rGFP, also known as Green Fluorescent Protein, is a protein produced by the jellyfish (Aequorea Victoria) that produces bioluminescence in the green zone of the noticeable spectrum. Green Fluorescent Protein is a useful and ubiquitous instrument for producing chimeric proteins, where it functions as a fluorescent protein tag. rGFP is expressed in most known cell types and is used as a noninvasive fluorescent marker in living cells and organisms. Green Fluorescent Protein permits a broad range of applications where it has functioned as a cell lineage tracer, reporter of gene expression, or as a measure of protein-protein interactions.

The somatomedins, or insulin-like growth factors (IGFs), comprise a family of peptides that play important roles in mammalian growth and development. IGF1 mediates many of the growth-promoting effects of growth hormone (GH; MIM 139250). Early studies showed that growth hormone did not directly stimulate the incorporation of sulfate into cartilage, but rather acted through a serum factor, termed 'sulfation factor,' which later became known as 'somatomedin' (Daughaday et al., 1972). Three main somatomedins have been characterized: somatomedin C (IGF1), somatomedin A (IGF2; MIM 147470), and somatomedin B (MIM 193190) (Rotwein, 1986; Rosenfeld, 2003).

PGAM1 is part of the phosphoglycerate mutase family. PGAM1 is an essential component of glucose and 2,3-BPGA (2,3-bisphosphoglycerate) metabolism and catalyzes the reversible reaction of 3-phosphoglycerate (3-PGA) to 2-phosphoglycerate (2-PGA) in the glycolytic pathway. PGAM1 is a dimeric enzyme containing, in different tissues, different proportions of a slow-migrating muscle (MM) isozyme, a fast-migrating brain (BB) isozyme, and a hybrid form (MB). PGAM1 mutations lead to muscle phosphoglycerate mutase deficiency, a.k.a. glycogen storage disease X.

The signal sequence receptor (SSR) is a glycosylated endoplasmic reticulum membrane receptor related with protein translocation across the ER membrane. The SSR consists of 2 subunits, a 34-kD glycoprotein (alpha-SSR or SSR1) and a 22-kD glycoprotein (beta-SSR or SSR2). The human beta-signal sequence receptor gene (SSR2) maps to chromosome bands 1q21-q23. Diseases correlated with SSR2 include calcaneonavicular coalition, and osteosarcoma, and among its related super-pathways are Viral mRNA Translation and Generic Transcription Pathway.

STEAP1 is principally expressed in prostate tissue, and is found to be upregulated in multiple cancer cell lines. The STEAP1 is predicted a six-transmembrane protein, and was shown to be a cell surface antigen significantly expressed at cell-cell junctions.

OSTF1 is an intracellular protein produced by osteoclasts that induces bone resorption, via signaling cascade which results in the secretion of factors enhancing osteoclast formation and activity.

MCM7 is a highly conserved mini-chromosome maintenance protein (MCM) vital for eukaryotic genome replication initiation. The MCM proteins form a hexameric protein complex which is a key component of the pre-replication complex (pre_RC) which takes part in replication forks formation and in DNA replication related proteins recruitment. The MCM complex is comprised of MCM2, 4, 6 and 7 proteins and possesses DNA helicase activity, such as DNA unwinding.

PPARGC1A is transcriptional coactivator for steroid receptors and nuclear receptors which increases the transcriptional activity of PPARG and thyroid hormone receptor on the uncoupling protein promoter. PPARGC1A regulates main mitochondrial genes that contribute to the program of adaptive thermogenesis and plays an important role in metabolic reprogramming in response to dietary availability through coordination of the expression of many genes participate in glucose and fatty acid metabolism. PPARGC1A induces the expression of PERM1 in the skeletal muscle and takes part in the integration of the circadian rhythms and energy metabolism.

GCSF is a cytokine that controls the production, differentiation, and function of granulocytes. The active protein is found extracellularly. Three transcript variants encoding three different isoforms have been found for this gene. Granulocyte/macrophage colony-stimulating factors are cytokines that act in hematopoiesis by controlling the production, differentiation, and function of 2 related white cell populations of the blood, the granulocytes and the monocytes-macrophages. This csf induces granulocytes.

NCS1 is part of the neuronal calcium sensor gene family, which encode calcium-binding proteins expressed primarily in neurons. NCS1 regulates G protein-coupled receptor phosphorylation in a calcium-dependent manner and can substitute for calmodulin. NCS1 is related with secretory granules and modulates synaptic transmission and synaptic plasticity. NCS1 regulates GRK1 and substitutes for calmodulin. NCS1 stimulates PI4KB kinase activity and participates in long-term synaptic plasticity through its interaction with PICK1. NCS1 takes part in neuron differentiation through inhibition of the activity of N-type voltage-gated calcium channel.

Type 1 cystatins are also called stefins which function as intracellular thiol protease inhibitors. Cystatin-B protein is able to form a dimer stabilized by noncovalent forces, inhibiting papain and cathepsins l, h and b. CSTB protein protects proteases leakage from lysosomes. Mutations in Stefin-B gene cause primary defects in patients with progressive myoclonic epilepsy (EPM1), a degenerative disease of the central nervous system. CSTB is overexpressed & elevated in the serum of HCC patients. Cystatin-B in vivo has a polymeric structure which is sensitive to the redox environment. Cystatin-B inhibits bone resorption by down-regulating intracellular cathepsin K activity despite increased osteoclast survival. Protein and mRNA levels of stefin B are significantly lower in atypical benign meningiomas. Stefins-A & Stefin-B which belong to the type-1 Cystatins, are up-regulated in lung tumours and thus able to counteract harmful tumour-associated proteolytic activity. Human stefin-A & Stef

CISD1 protein holds a CDGSH iron-sulfur domain and is known to bind a redox-active [2Fe-2S] cluster. CISD1 is restricted to the outer membrane of mitochondria and takes part in oxidation regulation.

CD14 (also known lipopolysaccharide (LPS) receptor) is expressed strongly on monocytes and macrophage and weakly on the surface of neutrophils. CD14 is anchored to cells by linkage to glycosylphosphatidylinositol (GPI) and functions as a high affinity receptor for complexes of LPS and LPS binding protein (LBP). Soluble CD14, also binding to LPS, acts at physiological concentration as an LPS agonist and has, at higher concentrations, an LPS antagonizing effect in cell activation. CD14 has been shown to bind apoptotic cells.

Acyl-CoA Thioesterase 7 (ACOT7) belongs to the acyl coenzyme family. ACOT7 hydrolyzes the CoA thioester of palmitoyl-CoA and other long-chain fatty acids. Decreased expression of the ACOT7 protein may be linked to mesial temporal lobe epilepsy.

Il-6 is a cytokine with a wide variety of biological functions: it plays an essential role in the final differentiation of b-cells into ig-secreting cells, it induces myeloma and plasmacytoma growth, it induces nerve cells differentiation, in hepatocytes it induces acute phase reactants.

Caseine Kinase 1 alpha belongs is a member of the protein kinase superfamily, CK1 Ser/Thr protein kinase family, Casein kinase I subfamily. The CK1 isoforms - alpha, beta, gamma, delta, epsilon and their splice variants are involved in diverse cellular processes including membrane trafficking, circadian rhythm, cell cycle progression, chromosome segregation, apoptosis and cellular differentiation. Possibly CSNK1A1 can phosphorylate a large number of proteins and is involved in Wnt signaling where it phosphorylates CTNNB1 on Ser45. CSNK1A1 also interacts with the Axin complex.

CD8 is a cell surface glycoprotein found on most cytotoxic T lymphocytes that mediates efficient cell-cell interactions within the immune system. CD8 acts as a co-receptor, and the T-cell receptor on the T lymphocyte recognize antigen displayed by an antigen presenting cell (APC) in the context of class I MHC molecules. The functional CD8 is either a homodimer composed of two alpha chains, or a heterodimer composed of one alpha and one beta chain. Both alpha and beta chains share significant homology to immunoglobulin variable light chains.
CD8 identifies cytotoxic/suppressor t-cells that interact with MHC class I bearing targets. CD8 is thought to play a role in the process of t-cell mediated killing. CD8 alpha chains binds to class-I MHC molecules alpha-3 domains.

Neisseria gonorrhoeae, also known as Gonococci is a Gram-negativebacteriahighly fastidiouscocci, requiring nutrient supplementation to survive. The cocci are facultatively intracellular and typically appear in pairs (diplococci).
Neisserial LPS is distinguished from enteric LPS by its highly-branched basal oligosaccharide structure and the absence of repeating O-antigen subunits. For these reasons, neisserial LPS is referred to as lipooligosaccharide (LOS). The bacterium characteristically releases outer membrane fragments called "blebs" during growth. These blebs contain LOS and probably have a role in pathogenesis if they are disseminated during the course of an infection.
Neisseria gonorrhoeae is a relatively fragile organism, susceptible to temperature changes, drying, uv light, and other environmental conditions. Strains of N. gonorrhoeae are variable in their cultural requirements so that media containing hemoglobin, NAD, yeast extract and other supplements are needed for isolation and growth of the organism.