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HSP70 is a human heat shock protein. HSP-70 is an important part of the cell''s machinery for protein folding, and help to protect cells from stress. In most species, there are many proteins that belong to the HSP70 family. Some of these are only expressed under stress conditions, while some are present in cells under normal growth conditions and are not heat-inducible. They can be found in different cellular compartments (nuclear, cytosolic, mitochondrial, endoplasmic reticulum, etc...).

The Fas receptor (CD95) mediates apoptotic signaling by Fas-ligand expressed on the surface of other cells. The Fas-FasL interaction plays an important role in the immune system and lack of this system leads to autoimmunity, indicating that Fas-mediated apoptosis removes self-reactive lymphocytes. Fas signaling is also involved in immune surveillance to remove transformed cells and virus infected cells. Binding of FAS to oligimerized FasL on another cell activates apoptotic signaling through a cytoplasmic domain termed the death domain that interacts with signaling adaptors including FAF, FADD and DAX to activate the caspase proteolytic cascade. Caspase-8 and caspase-10 are first activated, to then cleave and activate downstream caspases, and a variety of cellular substrates that lead to cell death. Caspases cleave nuclear lamins, causing the nucleus to break down and lose its normal structure and another caspase substrate is DFF, inducing cleavage and degradation of the genome. Other caspase substrates are involved in cytoskeletal structure, cell cycle regulation and signaling pathways. Activation of JNK kinase, activation of Jun, and production of ceramide may also play roles in Fas-mediated apoptosis. Activation of fas-mediated apoptosis is opposed by I-FLICE and FAP. Viruses and tumors may escape immune surveillance in part through suppression of fas-mediated apoptosis using similar mechanisms.

The Casein kinase 2 (EC 2.7.11.1) is a serine/threonine-selective protein kinase that is a tetramer of two alpha subunits and two beta subunits. The alpha subunits have the catalytic kinase domain. Casein kinase 2 has been implicated in cell cycle control, DNA repair, regulation of the circadian rhythm and other cellular processes. Casein kinase 2 activity has been reported to be activated following Wnt signaling pathway activation. A Pertussis toxin-sensitive G protein and Disheveled appear to be an intermediary between Wnt-mediated activation of the Frizzled receptor and activation of casein kinase 2. Mice that lack casein kinase 2 alpha prime have a defect in the morphology of developing sperm.

6PGD is the second dehydrogenase in the pentose phosphate shunt. Pentose is neccesary for nucleic acid biosynthesis. The pentose phosphate cycle is a major source of NADPH 6PGD deficiency is usually asymptomatic, and the inheritance of this disorder is autosomal dominant. PGD deficiency raises the erythrocyte pyruvate kinase levels of activity and decreases glutathione synthetase, resulting in hemolysis.

MAT2A is an important enzyme in cellular metabolism and catalyzes the formation of S-adenosylmethionine (SAMe) from L-methionine and ATP. MAT2A is expressed in extrahepatic tissues. In liver, MAT2A expression associates with growth, dedifferentiation, and cancer. NF-kappa B and AP-1 are necessary for basal MAT2A expression in HepG2 cells and mediate the increase in MAT2A expression in response to TNF-alpha. Up-regulation of MAT2A provides growth improvement and s-adenosylmethionine and methylthioadenosine thus can block mitogenic signaling in colon cancer cells. Lower expression of both MAT2A and MAT2beta and interfere with leptin signaling in liver cancer cells.

ReoVirus belongs to the RNA virus family of Reoviridae. The virions of reoviruses lack an outer envelope and show spheroidal. They measure approximately 70 nanometres and have two icosahedral capsids. Reoviruses enclose a core of segmented, double-stranded RNA virus and are a non-pathogenic naturally occurring virus. Approximately 100% of the population demonstrate signs of a previous reovirus infection, normally confined to the gastrointestinal or respiratory systems in the body. Reovirus particularly targets cells with a highly activated Ras signaling pathway and hence is a potent cancer killer.

EEF1A1 is an isoform of the alpha subunit of the elongation factor-1 complex, which is responsible for the enzymatic release of aminoacyl tRNAs to the ribosome. EEF1A1 is expressed in brain, placenta, lung, liver, kidney, and pancreas, and the other isoform (alpha 2) is expressed in brain, heart and skeletal muscle.

Cytokeratin 17 also known as KRT17 is a type I cytokeratin. KRT17 is found in nail beds, hair follicles, sebaceous glands, and other epidermal appendages. Mutations in KRT17 lead to Jackson-Lawler type pachyonychia congenita and steatocystoma multiplex. KRT17 takes part in the formation and maintenance of a variety of skin appendages, particularly in determining shape and orientation of hair. KRT17 also modulates the function of TNF-alpha in the precise context of hair cycling. Moreover, KRT17 regulates protein synthesis and epithelial cell growth all through binding to the adapter protein SFN and by stimulating Akt/mTOR pathway.

CBR1 is a NADPH-dependent, monomeric, and cytosolic enzyme which is related to a family of short-chain dehydrogenases/reductases. CBR1 protein (277 a.a.) is broadly spread in human tissues such as liver, epidermis, stomach, small intestine, kidney, neuronal cells, and smooth muscle fiber. CBR1 metabolizes numerous toxic environmental quinones and pharmacological relevant substrates such as the anticancer drug, doxorubicin. The best substrates of CBR1 are quinones, including ubiquinone-1 and tocophrolquinone (vitamin E).

ACADS is a tetrameric mitochondrial flavoprotein, which is part of the acyl-CoA dehydrogenase family. ACADS catalyzes the first step of the mitochondrial fatty acid beta-oxidation pathway. Mutations in ACADS have been associated with Short Chain Acyl-CoA Dehydrogenase Deficiency.

BCAT1 catalyzes the leading reaction in the catabolism of the indispensable branched chain amino acids isoleucine, leucine and valine.

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.

Cytokeratin 8 (KRT8) belongs to the type II keratin family clustered on the long arm of chromosome 12. Type I and type II keratins heteropolymerize to form intermediate-sized filaments in the cytoplasm of epithelial cells. KRT8 typically dimerizes with keratin 18 to form an intermediate filament in simple single-layered epithelial cells. KRT8 has a role in retaining cellular structural integrity and also functions in signal transduction and cellular differentiation. KRT8 gene mutations cause cryptogenic cirrhosis.

GDP Dissociation Inhibitor 1 (GDI1) is expressed mainly in neural and sensory tissues. GDI1 regulates the GDP/GTP exchange reaction of nearly all Rab proteins by inhibiting the dissociation of GDP from them, and the subsequent binding of GTP to them. GDI1 is also promoting the dissociation of GDP-bound Rab proteins from the membrane and inhibits their activation. Mutations in GDI1 have been associated with X-linked nonspecific mental retardation.

SARS Coronavirus is an enveloped virus containing three outer structural proteins, namely the membrane (M), envelope (E), and spike (S) proteins. Spike (S)-glycoprotein of the virus interacts with a cellular receptor and mediates membrane fusion to allow viral entry into susceptible target cells. Accordingly, S-protein plays an important role in virus infection cycle and is the primary target of neutralizing antibodies.It has recently been shown that SARS is caused by a human coronavirus. Human coronaviruses are the major cause of upper respiratory tract illness in humans, such as the common cold. Coronaviruses are positive-stranded RNA viruses, featuring the largest viral RNA genomes known to date (27-31 kb). The first step in coronavirus infection is binding of the viral spike protein, a 139-kDa protein, to certain receptors on host cells. The spike protein is the main surface antigen of the coronavirus. The most prominent protein in the culture supernatants infected with SARS virus is a 46 kDa nucleocapsid protein. This suggests that the nucleocapsid protein is a major immunogen that may be useful for early diagnostics.

BMP2 belongs to the transforming growth factor-beta (TGFB) superfamily. Bone morphogenic protein induces bone formation. BMP2 is a candidate gene for the autosomal dominant disease of fibrodysplasia (myositis) ossificans progressiva.

Iduronate 2-Sulfatase also known as IDS, belongs to the highly-conserved sulfatase family of enzymes which catalyze the hydrolysis of O-sulfate and N-salfate esters from a variety of substrates. IDS is essential for the lysosomal degradation of the glycosaminoglycans (GAG) heparan sulfate as well as dermatan sulfate. Furthermore, IDS hydrolyzes the 2-sulfate group of the IDS units of the GAG.

KLRD1, also known as Killer Cell Lectin Like Receptor D1, is expressed on the surface of natural killer cells in the innate immune system. KLRD1 functions as a receptor for the recognition of MHC class I HLA-E molecules by NK cells and some cytotoxic T-cells. KLRD1 can create disulfide-bonded heterodimer with NKG2 family members. CD94 & NKG2 complex interacts with (HLA)-E, Human Leukocyte Antigen on target cells on the surface of natural killer cells.

KRT20 is a member of the keratin family. The keratins are intermediate filament proteins responsible for the structural integrity of epithelial cells and are subdivided into cytokeratins and hair keratins. The type I cytokeratins consist of acidic proteins which are arranged in pairs of heterotypic keratin chains. This cytokeratin is a major cellular protein of mature enterocytes and goblet cells and is specifically expressed in the gastric and intestinal mucosa. The type I cytokeratin genes are clustered in a region of chromosome 17q12-q21.

PDCD4 is restricted to the nucleus in proliferating cells. Expression of PDCD4 is modulated by cytokines in natural killer and T cells. PDCD4 takes part in apoptosis. PDCD4 is a translation inhibitor targeted for degradation during tumor promotion. PDCD4 promotes colonic neoplastic transformation and tumor invasion. PDCD4 is an important target for microrna R-21 in breast cancer cells. Shortage of PDCD4 expression is associated with colorectal cancer. PDCD4 is swiftly phosphorylated by S6K1 kinase protein & afterwords degraded by ubiquitin ligase SCF in response to mitogens. PDCD4 in response to mitogens allows competent protein synthesis & cell growth. PDCD4 is a proapoptotic protein involved in TGF-beta1-induced apoptosis in human HCC cells, and a tumor suppressor in hepatocarcinogenesis. PDCD4 restraines tumor progression in colon carcinoma cells by the novel mechanism of down-regulating MAP4K1 transcription, with consequent inhibition of c-Jun activation and AP-1-dependent transcri

Estrogen receptors α (ERα, ER; NR3A1) is a member of the steroid hormone receptor family. ERα is a ligand-activated transcription factor. ERα contain DNA binding and ligand binding domains. ERα is expressed in a wide variety of tissues, including ovary, uterus, breast, prostate, testis, epididymis, bones, bladder, kidney, heart, vessel wall, pituitary gland and hypothalamus. ER plays a variety of important roles in the maintenance of the reproductive, cardiovascular, musculoskeletal and central nervous systems. The natural ligand for ER is 17β-estradiol, the classical estrogenic compound. The binding of estrogen to ER induces a conformational change and triggers a cascade of events, including dissociation from heat shock proteins, receptor dimerization, phosphorylation and the association of the hormone activated receptor with specific regulatory elements in target genes.

PDZK1 is a PDZ domain-containing scaffolding protein which facilitates localization of cell surface proteins and has a key part in cholesterol metabolism by regulating the HDL receptor, scavenger receptor class B type 1. Single nucleotide polymorphism in this gene is linked to metabolic syndrome, and overexpression results in drug resistance of multiple myeloma.

Shiga-like toxin (verotoxin) is a toxin produced by some strains of Escherichia coli. Shiga-like toxin is named for its similarity to the AB5-type Shiga toxin produced by the bacteria Shigella dysenteriae. There are two known types-SLT1 and SLT2. The Shiga-like toxin is linked with hemolytic-uremic syndrome. Shiga-like toxin requires highly specific receptors on the cells'' surface in order to attach and enter the cell. Species such as cattle, swine, and deer which do not carry these receptors may harbor toxigenic bacteria without any ill effect, dropping them in their feces, from where they may be distributed to humans. Shiga Like Toxin-1 Subunit B has nontoxic action, it is the functional region which binds to the receptor. The Shiga Like Toxin-1 Subunit B can be useful in vaccine study, antibody test and other functional research.

AK3L1 is an affiliate of the adenylate kinase family of enzymes. AK3L1 enzyme is restricted to the mitochondrial matrix. Adenylate kinases-3 regulates the adenine and guanine nucleotide compositions within a cell by means of catalyzing the reversible transfer of phosphate group among these nucleotides. 5 different isozymes of adenylate kinase have been identified in vertebrates. The enzyme expression of various adenylate kinase isozymes is growth regulated and tissue-specific.