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Killer Cell lectin-Like Receptor Subfamily K, Member 1 (KLRK1) is an activating receptor which has recently generated considerable interest. The most fascinating of these, are a couple of closely related proteins known as MICA and MICB. These are cell-surface molecules distantly related to MHC class I proteins, and their genes have elements of heat shock promoters. Thus, MICA and MICB are expressed in the course of cell stress and are up-regulated in tumor cells and during viral infections. This receptor-ligand combination has a crucial role in the immune response to various pathologies.

TSG101 is a member of apparently inactive homologs of ubiquitin-conjugating enzymes. TSG101 contains a coiled-coil domain that interacts with stathmin, a cytosolic phosphoprotein implicated in tumorigenesis. TSG101 is involved in cell growth and differentiation and acts as a negative growth regulator. TSG101 in vitro steady-state expression is important for maintenance of genomic stability and cell cycle regulation. TSG101 mutations and alternative splicing occur in high rate in breast cancer and implicate that defects occur during breast cancer tumorigenesis and/or progression. TSG101 is a factor of the ESCRT-I complex, a monitor of vesicular trafficking process. TSG101 binds to ubiquitinated cargo proteins and is needed for the sorting of endocytic ubiquitinated cargos into multivesicular bodies. TSG101 is needed for completion of cytokinesis and is involved in cell growth and differentiation.

Galectin-2 or LGALS2 is a protein, part of the galectin proteins family. The galectin proteins family holds galectin proteins family lectins that mediates adhesion between cells or cells to ECM. This family also take part in pre-mRNA splicing, apoptosis & tumor progression. Galectin-2 induces apoptosis in T cells that are activated & binds to lymphotoxin-a, also can implicatate on myocardial infarction. LGALS2 from human and mouse share about 65% amino acid sequence resemblance.

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. CSF-1 induces cells of the monocyte/macrophage lineage. It plays a role in immunological defenses, bone metabolism, lipoproteins clearance, fertility and pregnancy.

Synaptic vesicle membrane protein VAT-1 homolog (VAT1) is a member of the quinone oxidoreductase subfamily of zinc-containing alcohol dehydrogenase proteins. Synaptic vesicles are in charge of regulating the storage and release of neurotransmitters in the nerve terminal. VAT1 has an increased calcium ion-dependent expression in glioblastomas and on wounding, in basal keratinocytes. VAT1 is an abundant integral membrane protein of cholinergic synaptic vesicles and is believed to be involved in vesicular transport.

Receptor-associated Protein (aka RAP) averts the GCM-mediated enhancement of axon growth- ApoE-containing lipoproteins which are known to bind to receptors of the LDLr superfamily. In the presence of RAP, GCM doesn’t increase the axon extension rate in relation to base medium. Furthermore, the addition of RAP to the base medium doesn’t change the rate of axon extension. This implies that the growth stimulatory effect of apoE-containing lipoproteins secreted by glial cells is mediated by the LDLr family receptors. RAP annuls the growth stimulatory effect of GCM.

Salmonella Typhi is a pathogen causing typhoid fever, affecting over 17 million people with approximately 600,000 deaths annually worldwide. If untreated, typhoid fever cases result in mortality rates ranging from 12-30%.

Human T-lymphotropic virus (HTLV) is a human, single-stranded RNA retrovirus that causes T-cell leukemia and T-cell lymphoma. The virus activates a subset of T-helper cellscalled Th1cells. The result is a proliferation of Th1 cells and overproduction of Th1 related cytokines (mainly IFN-gamma and TNF-alpha). Feedback mechanisms of these cytokines cause a suppression of the Th2 lymphocytes and a reduction of Th2 cytokine production (mainly IL-4, IL-5, IL-10 and IL-13). The end result is a reduction in the ability of the infected host to mount an adequate immune response to invading organisms that require a predominantly Th2 dependant response (these include parasitic infections and production of mucosal and humoral antibodies).

Chemokine (C-X-C motif) ligand 10 (CXCL10) is a small cytokine belonging to the CXC chemokine family. CXCL10 is secreted by several cell types in response to IFN-?. These cell types include monocytes, endothelial cells and fibroblasts. CXCL10 has been attributed to several roles, such as chemoattraction for monocytes and T cells, promotion of T cell adhesion to endothelial cells, antitumor activity, and inhibition of bone marrow colony formation and angiogenesis. The gene for CXCL10 is located on human chromosome 4 in a cluster among several other CXC chemokines. This chemokine elicits its effects by binding to the cell surface chemokine receptor CXCR3. The three-dimensional crystal structure of this chemokine has been determined under 3 different conditions to a resolution of up to 1.92A.

Fractalkine soluble form is chemotactic for t-cells and monocytes, but not for neutrophils. Fractalkine membrane-bound form promotes adhesion of those leukocytes to endothelial cells. Fractalkine regulates leukocyte adhesion and migration processes at the endothelium and binds to CX3CR1. Natural Human Fractalkine is produced as a long protein (373-amino acid) with an extended mucin-like stalk and a chemokine domain on top. The mucin-like stalk permits it to bind to the cell surface. Fractalkine gene is located on human chromosome 16 along with some CC chemokines known as CCL17 and CCL22.

Lipocalin-2 also called Neutrophil Gelatinase Associated Lipocalin (NGAL) belongs to a family of lipocans which include 25 proteins (including a1-microglobulin and b-lactoglobulin), which are characterized by their ability to bind small lipophilic substances in their hydrophobic core.
They thereby serve as transporters of substances like retinal, biliverdins & prostaglandins. There are indications that NGAL is involved in modulation of the inflammatory response and is found in the plasma of patients after stroke.

Prolactin is a pituitary hormone involved in the stimulation of milk production, salt and water regulation, growth, development and reproduction. The initial step in its action is the binding to a specific membrane receptor (prolactin receptor) which belongs to the superfamily of class 1 cytokine receptors. The function of the prolactin receptor is mediated, at least in part, by two families of signaling molecules: Janus kinases and signal transducers and activators of transcription. Prolactin (PRL) is a hormone involved in a variety of important functions including ion transport and osmoregulation, stimulation of milk, protein synthesis as well as the regulation of numerous reproductive functions. PRL exerts its influence on different cell types through a signal transduction pathway which begins with the binding of the hormone to a transmembrane PRL receptor. Immunoreactive PRL receptor, a member of the cytokine receptor family, varies in size (short and long forms) with tissue source and species, from ~40 kDa to 100 kDa. The PRL receptor consists of at least three separate domains: an extracellular region with 5 cysteines which contains the prolactin binding site, a single transmembrane domain and a cytoplasmic region, the length of which appears to influence ligand binding and regulate cellular function.

Galectins are a family of animal lectins with an affinity for beta-galactosides. This family has at least 14 identified members. Galectins share similarities in the CRD (the carbohydrate recognition domain). Galectins are synthesized as cytosolic proteins. Though localized principally in the cytoplasm and lacking a classical signal peptide, galectins can also be stimulated to secretion by non-classical pathways or alternatively targeted to the nucleus. Galectins are involved in modulating cell-cell and cell-matrix interactions. Human Galectin-7 belongs to the prototypical Galectins containing a single CRD, which is initially identified in human epidermis as a monomer. The Galectin-7 expression is induced by tumor suppressor protein p53 and associated with apoptosis. Galectin-7 is a pro-apoptotic protein which functions intracellularlly upstream of JNK activation and mitochondrial cytochrome c release. The correlation of Galectin-7 with the UV-induced apoptosis of keratinocytes presents a critical mechanism in the maintenance of epidermal homeostasis. Human Galectin-7 is localized in both nucleus and cytoplasm.

VAMP3 is present in recycling endosomes and endosome-derived vesicles. VAMP3 has been implicated in recycling of transferrin receptors to the plasma membrane, secretion of alpha-granules in platelets, recycling of T-cell receptors to the immunological synapses, and membrane trafficking during cell migration. VAMP-3 is present in human platelets and necessary for granule secretion. Synaptobrevins are the main components of a protein complex involved in the docking and/or fusion of synaptic vesicles with the presynaptic membrane. VAMP3 high homology to other VAMPs in its broad tissue distribution and subcellular localization is shown to be the human equivalent of the rodent cellubrevin. In platelets the protein resides on a compartment that is not mobilized to the plasma membrane on calcium or thrombin stimulation.

Vesicle-Associated Membrane Protein 7 (VAMP7) is a member of the synaptobrevin family. VAMP7 is a transmembrane protein, which is a member of the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) family. VAMP7 is involved in the targeting and/or fusion of transport vesicles to their target membrane during transport of proteins from the early endosome to the lysosome. VAMP7 localizes to late endosomes and lysosomes and is involved in the fusion of transport vesicles to their target membranes. VAMP7 is essential for heterotypic fusion of late endosomes with lysosomes and homotypic lysosomal fusion. It is also necessary for calcium regulated lysosomal exocytosis. In addition, VAMP7 is involved in the export of chylomicrons from the endoplasmic reticulum to the cis Golgi. Furthermore, VAMP7 is needed for exocytosis of mediators during eosinophil and neutrophil degranulation, and target cell killing by natural killer cells.

RAC2 is a small signaling G protein/GTPase which is part of the RAS superfamily of small GTP-binding proteins which regulate cell growth, actin cytoskeletal organization, cell proliferation, survival, cell cycle progression, gene transcription rgulation and the activation of protein kinases. RAC2 cycles between an active gtp-bound and inactive gdp-bound state. In active state, RAC2 binds to a variety of effector proteins to regulate cellular responses, such as secretory processes, phagocytose of apoptotic cells and epithelial cell polarization. RAC2 is involved in the regulation of the nadph oxidase.

Ribosomes, the organelles which catalyze protein synthesis, contain a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and nearly 80 structurally different proteins. RPL35A is a component of the 60S subunit of the ribosomal protein and a member of the L35AE family of ribosomal proteins. RPL35A is situated in the cytoplasm. The rat protein is known to bind to both initiator and elongator tRNAs, therefore, it is located at the P site, or P and A sites, of the ribosome. Though RPL35A was initially mapped to chromosome 18, it has been proven that it is located at 3q29-qter. Transcript variants utilizing alternative transcription initiation sites and alternative polyA signals exist. As is typical for genes encoding ribosomal proteins, there are several processed pseudogenes of this gene spread all over the genome.

40S ribosomal protein S13 (RPS13), is a member of the ribosomal protein S15P family. Ribosomes are the organelles which catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. RPS13 is located in the cytoplasm and contains multiple phosphorylated residues. Similar to other ribosomal proteins, Ribosomal Protein S13 exists as multiple processed pseudogenes which are scattered throughout the genome.

Hepatitis E virus (HEV), the major etiologic agent of enterically transmitted non-A, non-B hepatitis worldwide, is a spherical, non-enveloped, single stranded RNA virus that is approximately 32 to 34 nm in diameter. HEV belongs to a genus of HEV-like viruses (unassigned genus). HEV has a single-stranded polyadenylated RNA genome of approximately 8 kb. Based on its physicochemical properties it is presumed to be a calici-like virus.

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.

Since April 2012, cases of the Middle East Respiratory Syndrome Coronavirus (MERS-CoV) have been identified in the following countries: Saudi Arabia, Qatar, Jordan, the United Arab Emirates, Oman, Kuwait, Yemen, Lebanon, Iran, Algeria, the United Kingdom, France, Italy, Greece, Germany, the Netherlands, Austria, Tunisia, Egypt, Malaysia, Turkey and the United States of America. Coronaviruses are the cause of the common cold, SARS (severe acute respiratory syndrome) and other severe illnesses with high mortality rates, all are classified into coronavirus family. MERS-CoV is a new type of SARS found in the coronavirus family causing severe pneumonia with sudden and serious respiratory illness with high mortality rates as well. Since January 27th 2015, the WHO has reported 956 human cases, including 351 deaths. More cases of the new coronavirus strain are expected. Like in other coronaviruses, large surface spike glycoprotein is a central structural protein of this virus; it is located above the virion surface to bind and enter into the target cell. Spike protein has 2 domains- S1 and S2. The S1 domain is responsible for cellular tropism and interaction with target cell, while the S2 domain is responsible for membrane fusion. The C-terminal of S1 domain contains a receptor binding domain, and is also a potential target for vaccine development and an antigen for diagnosis.

IFNI30 inducible lysosomal thiol reductase (IFI30), is a part of the GILT family. IFI30 is a lysosomal thiol reductase which at low pH is capable of decreasing protein’s disulfide bonds. IFI30 is expressed constitutively in antigen-presenting cells and induced by gamma-IFN in other cell types. Also, IFI30 plays an important role in MHC class II-restricted antigen processing. IFI30 facilitates the generation of MHC class II-restricted epitopes from disulfide bond-containing antigen by the endocytic reduction of disulfide bonds and Also facilitates MHC class I-restricted recognition of exogenous antigens containing disulfide bonds by CD8+ T-cells or cross-presentation.