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Listeriolysin O (aka LLO) is a hemolysin produced by Listeria monocytogenes bacteria, the pathogen responsible for causing listeriosis. The toxin may be regarded as a virulence factor, since it is crucial for the virulence of L. monocytogenes. LLO is a single polypeptide protein encoded by the hlyA gene and composed of 529 residues. LLO is a thiol-activated cholesterol-dependent pore forming toxin protein; therefore, it is activated by reducing agents and inhibited by oxidizing agents. Still, LLO differs from other thiol-activated toxins, as its cytolytic activity is maximized at a pH of 5.5. Inside the acidic phagosomes (average pH ~ 5.9) of cells that have phagocytosed L. monocytogenes, LLO is selectively activated by maximizing activity at a pH of 5.5. Following the phagosome lysis by LLO, the bacterium breaks out into the cytosol, where it is able to grow intracellularly, and the toxin has reduced activity in the more basic cytosol. Thus, LLO permits L. monocytogenes to break out from the phagosomes into the cytosol without harming the plasma membrane of the infected cell, which allows the bacteria to live intracellularly, where they are sheltered from extracellular immune system factors such as the complement system and antibodies. LLO also brings about dephosphorylation of histone H3 and deacetylation of histone H4 in the early phases of infection, before entry of L. monocytogenes into the host cell. The pore-forming activity is not implicated in causing the histone modifications. The modifications of the histones affect the down regulation of genes encoding proteins involved in the inflammatory response. Therefore, LLO may be significant in subverting the host immune response to L. monocytogenes. At its NH2-terminus it possesses a 25 residues long typical signal sequence excited during the secretion process. Moreover, in its NH2-terminus there is also a 19 amino acids PEST- like sequence that may target this toxin for degradation. The PEST-like sequence found in LLO and is considered crucial for virulence, given that mutants lacking the sequence lysed the host cell. Nevertheless, contrary to PEST's supposed role in protein degradation, evidence implies that the PEST-like sequence may control LLO production in the cytosol rather than increase degradation of LLO.

Geminin is a 25 kDa nuclear protein, which inhibits DNA replication and is degraded during the mitotic phase of the cell cycle. Geminin controls replication by binding to the licensing factor Cdt1, and is involved in neural differentiation. In addition, Geminin directly interacts with Six3 and Hox homeodomain proteins during embryogenesis and inhibits their functions. Geminin can also promote DNA replication. Geminin has 2 roles in 2 different stages of the cell cycle: Geminin is a negative regulator of DNA replication during the “S phase” of the cell cycle. Inhibition of Geminin during the “S phase” (by RNAi) results in an additional round of replication of portions of the genome. During the “M phase” of the cell cycle (mitosis) Geminin stabilizes the replication factor Cdt1 promoting DNA replication during the next cell cycle. Moreover, inhibition of Geminin during mitosis (by RNAi) causes destabilization of Cdt1 protein and impairment of DNA replication during the next cell cycle. Geminin thus guarantees that only one round of replication occurs during each cell cycle. It was discovered that Geminin is overexpressed in a number of malignancies and cancer cell lines. This maintains the concept that Geminin has also a positive role in DNA replication and cell cycle progression. Geminin accumulates through S, G2 and M phases of the cell cycle but is absent during the G1 phase. During the metaphase/anaphase transition of mitosis Geminin levels decrease.

Prorelaxin H2 (RLN2) is a member of a family which is produced by the ovary, targets the mammalian reproductive system to ripen the cervix, elongate the pubic symphysis and inhibit uterine contraction. It may also have other roles in boosting sperm motility, regulating blood pressure, controlling heart rate and releasing vasopressin. RLN2 is a peptide hormone linked to several therapeutically relevant physiological effects, including regulation of collagen metabolism and multiple vascular control pathways. The active form of the RLN2 protein consists of an A chain and a B chain linked by disulfide bonds.

Alpha-hemoglobin stabilizing protein (AHSP) is an erythroid-specific protein that acts as a chaperone to prevent the aggregation of A-hemoglobin during normal erythroid cell development. AHSP specifically protects free A-hemoglobin from precipitation in live cells and in solution. AHSP is expected to modulate pathological states of alpha-hemoglobin excess such as beta-thalassemia. Furthermore, AHSP promotes alpha globin chain stability in human erythropoiesis. In addition, the AHSP stabilizes the alpha-Hb chain, thus avoiding its precipitation and its ability to generate ROS, which is implicated in cell death. AHSP is expressed in blood and bone marrow. AHSP subunit is a monomer, it forms a heterodimer with free alpha-hemoglobin. On the other hand, AHSP does not bind beta-hemoglobin nor alpha2beta2 hemoglobin A. AHSP is downregulated in TSEs (transmissible spongiform encephalopathies).

Inhibins are dimeric peptide hormones produced by female ovarian granulose cells and male Sertoli cells as well as a variety of other tissues. Inhibins have two isoforms, A and B, with the same alpha subunit but different beta subunits. Inhibin A is a dimer of alpha and beta A subunits, inhibin B is a dimer of alpha and beta B subunits.
Inhibins are thought to inhibit the production of follicle-stimulating hormone (FSH) by the pituitary gland. In addition, Inhibins are also thought to play a role in the control of gametogenesis, and embryonic and fetal development.

Cathepsin D is synthesized as a 54kDa precursor, which is proteolytically processed to an intermediate 48kDa single chain, which matures into more stable 34kDa and 14kDa two chain form. It is an estrogen-regulated lysosomal protease that has been suggested to facilitate cancer cell migration and invasion by digesting the basement membrane, extracellular matrix, and xonnective tissue. Because of its mitogenic and proteolytic activities, it has been implicated as a prognostic marker in many tumor types. Cathepsin D is expressed in epithelial cells as well as in macrophages.

Meteorin (METRN) is involved in both glial cell differentiation and axonal network formation during neurogenesis. METRN promotes astrocyte differentiation and transforms cerebellar astrocytes into radial glia. Moreover, the METRN protein stimulates axonal extension in small and intermediate neurons of sensory ganglia by activating nearby satellite glia.

Leptin takes an important part in the regulation of energy balance and body weight control.After entering the circulation, Leptin binds LEPRwhich results in the activation of several major signalling pathways. In the hypothalamus Leptin acts as an appetite-regulating factor that induces a decrease in food intake and an increase in energy consumption and also regulates bone mass and secretion of hypothalamo-pituitary-adrenal hormones. In the periphery, increases basal metabolism, regulates pancreatic beta-cell function and insulin secretion and affects innate and adaptive immunity.

Leptin is a protein hormone with important effects in regulating body weight, metabolism and reproductive function. The protein is approximately~16 kDa in mass and encoded by the obese (ob)gene. leptin is expressed predominantly by adipocytes, which fits with the idea that body weight is sensed as the total mass of fat in the body. Smaller amounts of leptin are also secreted by cellsin the epithelium of the stomach and in the placenta. Leptin receptors are highly expressed in areas of the hypothalamus known to be important in regulating body weight, as well as in T lymphocytes and vascular endothelial cells.

Galanin Prepropeptide (GAL) which is localized in brain pathways is involved in both cognition and affect, and also inhibits learning and memory by inhibiting neurotransmitter release and neuronal firing rate. GAL is a part of the galanin family and modulates a variety of physiological processed including cognition/memory, sensory/pain processing, neurotransmitter/hormone secretion, and feeding behavior. Galanin Prepropeptide is upregulated in primary afferent and sympathetic neurones and is required for the development of sympathetic perineuronal baskets subsequent to nerve injury.

EPCAM is a carcinoma-associated antigen and belongs to a family which includes at least 2 type I membrane proteins. The EPCAM protein has a role in embryonic stem cells proliferation and differentiation. EPCAM is used as a target for immunotherapy treatment of human carcinomas. EPCAM is expressed on most normal epithelial cells and gastrointestinal carcinomas and acts as a homotypic calcium-independent cell adhesion molecule. Epithelial cell adhesion molecules (EPCAM) can act as a physical homophilic interaction molecule between intestinal epithelial cells (IECs) and intraepithelial lymphocytes (IELs) at the mucosal epithelium for supplying immunological barrier as a first line of defense against mucosal infection. EPCAM gene mutations result in congenital tufting enteropathy.

Allergen Fra e 1.0101 (Fra e 1.0101) causes an allergic reaction in humans.

Angiotensin is an oligopeptide in the blood that causes vasoconstriction, increased blood pressure, and release of aldosterone from the adrenal cortex. It is a powerful dipsogen. It is derived from the precursor molecule angiotensinogen, a serum globulin produced in the liver. It plays an important role in the renin-angiotensin system.
The protein encoded by this gene, pre-angiotensinogen or angiotensinogen precursor, is expressed in the liver and is cleaved by the enzyme renin in response to lowered blood pressure. The resulting product, angiotensin I is then cleaved by angiotensin converting enzyme (ACE) to generate the physiologically active enzyme angiotensin II. The protein is involved in maintaining blood pressure and in the pathogenesis of essential hypertension and preeclampsia.

CAMP belongs to the antimicrobial peptide family, contains highly conserved N-terminal signal peptide, a cathelin domain and a structurally variable cationic antimicrobial peptide that produced by extracellular proteolysis from the C-terminus. CAMP has numerous functions besides the antimicrobial activity such as: cell chemotaxis, immune mediator induction and inflammatory response regulation.

The OmpA protein is one of the main outer-membrane proteins of a large array of Gram-negative bacteria such as A.salmonicida, Shigella dysenteriae and E.coli.OmpA’s major physiological functions include maintenance of the structural integrity and morphology of the cells and porin activity, as well as a role in conjugation and bacteriophage binding.Achromogenic atypical Aeromonas salmonicida is the causative agent of goldfish ulcer disease.Virulence of this bacterium is associated with the production of a paracrystalline outer membrane A-layer protein.The species specific structural gene for the monomeric form of A-protein was cloned into a pET-3d plasmid in order to express and produce a recombinant form of the protein in E.coli BL21(DE3). The induced protein was isolated from inclusion bodies by a simple solubilization-renaturation procedure and purified by ion exchange chromatography on Q-Sepharose to over 95% pure monomeric protein.Recombinant A-protein was compared by biochemical, immunological and molecular methods with the A-protein isolated from atypical A.salmonicida bacterial cells by the glycine and the membrane extraction methods.

The recombinant Protein A/G is a genetically engineered protein comprised of 7 IgG-binding domains EDABC-C1C3, corresponding to the Protein A and G domains which are included in the recombinant sequence. The Protein A part is from Staphylococcus aureus segments E, D, A, B and C. The Protein G part is from Streptococcus segments C1 and C3. The recombinant Protein A/G has a broader binding capacity than either Protein A or Protein G alone. The recombinant Protein A/G is ideal for purification of monoclonal or polyclonal IgG antibodies. Protein A/G binds to various human, mouse and rat IgG subclasses such as the human IgG1, IgG2, IgG3, IgG4; mouse IgG2a, IgG2b, IgG3 and rat IgG2a, IgG2c. In addition, Protein A/G binds to total IgG from cow, goat, sheep, horse, rabbit, guinea pig, pig, dog and cat.

S100A10 is a member of the S100 family of proteins contains two EF-hand calcium-binding motifs and is thought to be involved in the regulation of a number of cellular processes including cell cycle progression and differentiation. S100 proteins are localized either in the cytoplasm or the nucleus of a wide range of cells. There are at least 13 members in the S100 gene family, which are located as a cluster on chromosome 1q21. S100A10 may function in exocytosis and endocytosis.

AMRC10 is a protein which contains an armadillo repeat and transmembrane domain. Upregulation of the AMRC10 gene has a role in hepatocellular carcinoma. AMRC10 decreases the transcriptional activity of the tumor suppressor protein p53 through direct interaction with the DNA-binding domain of p53, moreover it might play a role in cell growth and survival.

P-Selectin also called Platelet Alpha-Granule Membrane Protein, CD62, and Granulocyte Membrane Protein GRMP belongs to a family of divalent cation-dependent carbohydrate-binding glycoproteins or adhesion molecules. Pselectin is expressed transiently on the surface of activated platelets and endothelial cells. P-Selectin is a 140 kDa protein which is stored in the alpha-granules of platelets and Weibel-Palade bodies of endothelial cells. Secreted P-selectin is thought to play a key role in the adhesion of platelets to monocytes and neutrophils during an inflammatory response. P-Selectin is a calcium-dependent receptor that binds to sialylated forms of Lewis blood group carbohydrate antigens on neutrophils and monocytes. Levels of P-Selectin may be elevated in a number of pathological conditions.

Tubulointerstitial Nephritis Antigen Like 1 also known as TINAGL1 is similar in sequence to tubulointerstitial nephritis antigen, a secreted glycoprotein which is identified by antibodies in several types of immune-related tubulointerstitial nephritis. Three transcript variants encoding different isoforms are known for TINAGL1.

Filamin is a large (270kd) dimeric actin crosslinking protein from a variety of sources, which helps to stabilize the 3D cortical actin network. The fundamental structure of filamin is well conserved and consists of an actin binding domain at the N-terminus followed by a C-terminal rod domain consisting of numerous repeat segments ranging from 4 in C. elegans to 24 in mammalian cells. Each repeat in the rod domain consists of roughly 100 residues and forms an immunoglobulin like fold. Such immunoglobulin folds have been found in a variety of proteins and are responsible for protein-protein interactions. Filamin Human actin-binding protein (ABP), aka filamin, crosslinks actin filaments into orthogonal networks in cortical cytoplasm and participates in the anchoring of membrane proteins for the actin cytoskeleton. Mammalian filamin interacts directly with at least 30 proteins such as transmembrane receptors, second messenger-associated proteins, protein kinases, phosphatases and cytoskeletal proteins and these interactions have been shown to require one or more of the repeat elements in the rod domain.