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Heat-stable enterotoxins (STa) are small, cysteine-rich peptides secreted by Escherichia coli that are able to induce diarrhea through the stimulation of an intestine-specific receptor-guanylyl cyclase known as STaR. Binding of STa to STaR induces a dramatic increase in the cGMP content of the cell; the increase, in turn, inhibits salt absorption and stimulates chloride secretion. This imbalance of ions is accompanied by a massive accumulation of water in the gut that gives rise to the diarrhea and dehydration characteristic of enterotoxin activity. The identification of a receptor for STa on intestinal brush border membranes suggested the existence of an endogenous activator, described guanylin, a 15-amino acid peptide purified from rat small intestine, as a potential ligand for the STaR. This peptide shares sequence similarity with STa; see also uroguanylin. The molecular cloning of the human and mouse cDNAs encoding guanylin was reported. The sequences demonstrated that guanylin is present at the C-terminal end of a larger precursor protein. Expression in mammalian cells indicated that the 94- amino acid proguanylin is inactive. The biologically active guanylin can be released by either chemical or enzymatic treatment of proguanylin. By Northern blot analysis and in situ hybridization, showed that expression of guanylin mRNA is restricted to cells of the intestinal epithelium, specifically the Paneth cells at the base of the small intestinal crypts. These results demonstrate that guanylin is an endogenous activator of STaR isolated a cDNA encoding an apparent precursor of guanylin from a human intestinal cDNA library. The mRNA was expressed at high levels in human ileum and colon. In the mouse, interspecific backcross analysis used to map the Guca2 gene to the distal half of mouse chromosome 4 in a region of homology with human chromosome 1p. By fluorescence in situ hybridization mapped the GUCA2 gene to human 1p35-p34 Guanylin is thought to modulate intestinal water/electrolyte transport in a paracrine mode reported the nucleotide sequence of the gene, the characteristics of its circulating molecular form, and its localization in enterochromaffin cells of the gut. The gene, approximately 2.6 kb in size, consists of 3 exons interrupted by 2 introns. The hormonal form of guanylin is a 94-amino acid peptide with a molecular mass of 10.3 kDa. Guanylin is synthesized by gut enterochromaffin cells as a prohormone of 115 amino acids and is processed to the molecular form of 94 amino acids circulating in the blood.

MAEA is a 396aa widely expressed adhesion protein which has 5 alternatively spliced isoforms. MAEA holds one CTLH domain and one LisH domain. MAEA forms a complex with F-actin, which takes part in regulating actin distribution in erythroblasts and macrophages and is known to assist in cell division and nuclear architecture. MAEA is confined with condensed chromatin at prophase, nuclear spindle poles at metaphase and in the contractile ring throughout cytokinesis phase and telophase.

Type IV collagen is a major structural component of basement membranes. It is a multimeric protein composed of 3 alpha subunits, which are encoded by 6 different genes, alpha 1 through alpha 6. Each of these alpha subunits can form a triple helix structure with 2 other subunits to form type IV collagen. The Goodpasture syndrome is a condition in which autoantibodies bind to the collagen molecules in the basement membranes of alveoli and glomeruli. The epitopes that elicit these autoantibodies are restricted basically to the non-collagenous C-terminal domain of the protein. There are numerous alternative transcripts that appear to be unique to the human COL4A3 and alternative splicing is limited to the six exons that encode this C-terminal domain. COL4A3 is also linked to an autosomal recessive form of Alport syndrome. The mutations contributing to the Alport syndrome are also situated within the exons that encode this C-terminal region. COL4A3 is organized in a head-to-head conformation with another type IV collagen gene so that each gene pair shares a common promoter. Several exons of COL4A3 are interspersed with exons of an uncharacterized gene which is on the opposite strand.

Maltose Binding Protein is a member of the maltose/maltodextrin system of E.Coli, which is accountable for the uptake and efficient catabolism of maltodextrins. The maltose/maltodextrin is a complex regulatory and transport system involving many proteins and protein complexes.
MBP elevates the yield of its fusion partner in many cases and is often able to promote the solubility of polypeptides to which it is fused.

FGF8 is part of the fibroblast growth factor family. FGF family members have wide mitogenic and cell survival activities, and participate in a variety of biological processes, including embryonic development, cell growth, morphogenesis, tissue repair, tumor growth and invasion. FGF8 supports androgen and anchorage independent growth of mammary tumor cells. FGF8 over expression increases tumor growth and angiogensis. The adult expression of FGF-8 gene is restricted to testes and ovaries. FGF8 functions as an embryonic epithelial factor. FGF8 takes part in midbrain and limb development, organogenesis, embryo gastrulation and left-right axis determination.

Fibroblast Growth Factor 17 (FGF17) belongs to the fibroblast growth factor (FGF) family. FGF family members have broad mitogenic and cell survival activities, and are involved in various biological processes including embryonic development cell growth, morphogenesis, tissue repair, tumor growth and invasion. The FGF17 gene is highly expressed in the cerebellum and cortex. The mouse homolog of the FGF17 gene is localized to specific sites in the midline structures of the forebrain, the midbrain-hindbrain junction, developing skeleton and developing arteries, suggesting a role in central nervous system, bone and vascular development.

TFPI is a protease inhibitor which controls the tissue factor (TF)-dependent pathway of blood coagulation. The coagulation process starts with the creation of a factor VIIa-TF complex, that proteolytically triggers additional proteases (factors IX and X) and eventually results in a fibrin clot. TFPI inhibits the activated factor X and VIIa-TF proteases in an autoregulatory loop. TFPI is glycosylated and predominantly located in the vascular endothelium and plasma in both free forms and complexed with plasma lipoproteins. A number of alternatively spliced transcript variants of this gene have are known, however the full-length nature of several of these variants were not yet established.

CCL3L1 is a small cytokine that belongs to the CC chemokines. The CCL3L1 gene is one of several cytokine genes clustered on the q-arm of chromosome 17. CCL3L1 is involved in immunoregulatory and inflammatory processes. CCL3L1 binds to several chemokine receptors including CCBP2 and CCR5. CCR5 is a co-receptor for HIV, and binding of the CCL3L1 protein to CCR5 inhibits HIV entry.

Eosinophil lysophospholipase (CLC) acts on biological membranes to regulate the multifunctional lysophospholipids. CLC is a lysophospholipase expressed in eosinophils and basophils. CLC hydrolyzes lysophosphatidylcholine to glycerophosphocholine and a free fatty acid. The CLC protein may possess carbohydrate or IgE-binding activities. CLC is both structurally and functionally related to the galectin family of beta-galactoside binding proteins. CLC may be linked with inflammation and some myeloid leukemias.

Cofilin is a family of actin-binding proteins which disassembles actin filaments. It is a widely distributed intracellular actin-modulating protein that binds and depolymerizes filamentous F-actin and inhibits the polymerization of monomeric G-actin in a pH-dependent manner. It is involved in the translocation of actin-cofilin complex from cytoplasm to nucleus.

Glutaredoxin-2 (GrxB) is amember of the glutaredoxin family. Glutaredoxins are small redox enzymes of approximately 100 amino-acid residues which use glutathione as a cofactor. Glutaredoxins are oxidized by substrates, and reduced non-enzymatically by glutathione. GrxB is involved in reducing some disulfides in a coupled system with glutathione reductase. GrxB doesn’t act as hydrogen donor for ribonucleotide reductase.

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.

Osteopontin is a glycoprotein that was first identified in osteoblasts and is involved in bone remodeling, immune functions in fibroblasts, macrophages, and lymphocytes during inflammation and wound healing. SPP1 binds tightly to hydroxyapatite. SPP1 forms an integral part of the mineralized matrix. SPP1 is vital to cell-matrix interaction.
Secreted Phosphoprotein-1 protects against cardiac ischemia-reperfusion injury via late preconditioning. Expression of both Ostepontin and CD44 in hepatocellular carcinoma is linked with advanced tumor stage and contributes to prognosis information. SPP1 is the most over-expressed gene in intrahepatic cholangiocarcinoma. Secreted Phosphoprotein-1 overexpression is related with interstitial lung diseases.

Dickkopf-related protein 1 (DKK1) antagonizes canonical Wnt signaling by inhibiting LRP5/6 interaction with Wnt and by creating a ternary complex with the transmembrane protein KREMEN which promotes internalization of LRP5/6. DKKs have a significant role in vertebrate development, where they locally inhibit Wnt controlled processes for instance antero-posterior axial patterning, limb development, somitogenesis and eye formation. Furthermore, Dkks are involved in bone formation and bone disease, cancer and Alzheimer disease in Adults.

The acute phase plasma protein ORM1 synthesized by the liver mediates the interaction between blood cells and endothelial cells. In addition, together with haptoglobin and C reactive protein, ORM1 regulates the extravasation of the cells through infection and inflammation. Expression of ORM1 is induced by acute-phase stimulatory mediators such as bacterial lipopolysaccharides.

Vimentin expression in human malignant glioma cells depends on cellular density, algorithms of drug delivery and chemo/radio treatment. Vimentin and detyrosinated microtubules provide structural support for the extensive microtentacles observed in detached tumor cells and a mechanism to promote successful metastatic spread. Primary colorectal carcinomas display aberrant expression of vimentin, and have activated Notch and TGFbeta signaling pathways. Vimentin is a strong arterial substrate for transglutaminases. Transglutaminase-mediated vimentin dimerization results in a novel unifying pathway by which vasodilatory and remodeling responses may be regulated. Ablation of vimentin expression inhibits migration and invasion of colon and breast cancer cell lines. Vimentin is the main intermediate filament protein in mesenchymal cells and is therefore of value in the differential diagnosis of undifferentiated neoplasms.

GIPC2 is a 315 aa protein which is restricted to the cytoplasm and holds one PDZ domain. GIPC2 is expressed in large quantities in colon and kidney and in small quantities in adult liver. GIPC2 has a vital part in human gastric cancer by control of growth factor signaling or cell adhesion.

GNMT is an enzyme that catalyzes the conversion of S-adenosyl-L-methionine with glycine to S-adenosyl-L-homocysteine and sarcosine. GNMT is located in the cytoplasm and acts as a homotetramer. Defects in the GNMT gene causes of GNMT deficiency (hypermethioninemia). GNMT affects DNA methylation by regulating the ratio of S-adenosylmethionine to S-adenosylhomocystine and is involved in the detoxification pathway in liver cells. GNMT expression is diminished in human hepatocellular carcinoma (HCC). GNMT catalyzes the methylation of glycine by using s- adenosylmethionine (adomet) to form n-methylglycine (sarcosine) with the concomitant production of s-adenosylhomocysteine (adohcy). GNMT plays an essential role in the regulation of tissue concentration of adomet and of metabolism of methionine.

COP9 Signalosome Subunit 7A (COPS7A) is a component of the COP9 signalosome complex (CSN), a complex involved in a variety of cellular and developmental processes. The CSN complex is a vital regulator of the ubiquitin (Ubl) conjugation pathway by mediating the deneddylation of the cullin subunits of SCF-type E3 ligase complexes, thus leading to decrease in the Ubl ligase activity of SCF-type complexes such as SCF, CSA or DDB2. This complex is also involved in phosphorylation of p53/TP53, JUN, I-kappa-B-alpha/NFKBIA, ITPK1 and IRF8/ICSBP, probably through its association with CK2 and PKD kinases. CSN-dependent phosphorylation of TP53 and JUN stimulates and protects degradation by the Ubl system, respectively.

Epidermal growth factor has a profound effect on the differentiation of specific cells in vivo and is a potent mitogenic factor for a variety of cultured cells of both ectodermal and mesodermal origin. The EGF precursor is believed to exist as a membrane-bound molecule which is proteolytically cleaved to generate the 53-amino acid peptide hormone that stimulates cells to divide. EGF stimulates the growth of various epidermal and epithelial tissues in vivo and in vitro and of some fibroblasts in cell culture. Long EGF is a recombinant analog of Human EGF developed as a replacement for use in therapeutic cell culture applications as a like-for-like supplement for Recombinant Human or native EGF. It includes the Human EGF amino acid sequence plus a 53 amino acid N-terminal extension peptide.

MALD3 (a non-specific lipid transfer protein) is a major apple allergen. LTPs are found mainly in aerial plant organs such as leaves, seeds, flowers, and fruit. MALD3 is a heat-stable protein which is characterized by having resistance to pepsin hydrolysis.

LGALS8 is a prostate-specific antigen that is solely overexpressed in malignant tumors and thus is a supplementary specific identifier of malignancies. LGALS8 is part of the galectin gene family which facilitates both cell-cell and cell matrix interactions in a method parallel to the selectin subgroup of C-type lectins.