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MICA (MHC class I chain-related gene A) is a transmembrane glycoprotein that functions as a ligand for human NKG2D. A closely related protein, MICB, shares 85% amino acid identity with MICA. These proteins are distantly related to the MHC class I proteins. They possess three extracellular Ig-like domains, but they have no capacity to bind peptide or interact with ?2-microglobulin. The genes encoding these proteins are found within the Major Histocompatibility Complex on human chromosome 6. The MICA locus is highly polymorphic with more than 50 recognized human alleles. MICA is absent from most cells but is frequently expressed in epithelial tumors and can be induced by bacterial and viral infections. MICA is a ligand for human NKG2D, an activating receptor expressed on NK cells, NKT cells, gamma delta T cells, and CD8+ beta T cells. Recognition of MICA by NKG2D results in the activation of cytolytic activity and/or cytokine production by these effector cells. MICA recognition is involved in tumor surveillance, viral infections, and autoimmune diseases.

Cytokeratin 8 belongs to the type B (basic) subfamily of high molecular weight keratins and exists in combination with keratin 18. Cytokeratin 8 is primarily found in the non-squamous epithelia and is present in majority of adenocarcinomas and ductal carcinomas. It is absent in squamous cell carcinomas. Hepatocellular carcinomas are defined by the use of antibodies that recognize only cytokeratin polypeptides 8 and 18.

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. G

TPT1 takes part in calcium binding and microtubule stabilization. TPT1 is an immunoglobulin E dependent histamine-releasing factor produced by lymphocytes of atopic children and present in biologic fluids of allergic patients. TPT1 protein is similar to p23, a protein of Ehrlich ascites tumor cells, synthesized in the exponentially growing tumor. TPT1 is similar with IgE-dependent histamine releasing factor. TPT1 has a cell housekeeping function. TPT1 is involved in spermatogenesis and acts as a calcium binding protein of the human placenta that regulates calcium handling in trophoblast cells.

Neural Cell Adhesion Molecule 1 (NCAM1) is apart of the immunoglobulin superfamily. NCAM1 bindsspecifically to neurite fasciculation, neuronneuron adhesion, outgrowth of neurites, and more. The polysialyation of NCAM1 reduces its adhesive property and increases its neurite outgrowth promoting features.NCAM1is mainly expressed in NK cells and a subset of T lymphocytes that mediate MHC-unrestricted cellmediated cytotoxicity. High expression of NCAM-1 differentiates NK cells as having an activated phenotype. During hematopoiesis, NCAM1plays a role as the prototypic marker of NK cells and also present on subset of CD4+, CD8+ and T cells. In cell adhesion, NCAM1 contributes to cell-cell adhesion during embryonic development.

Synaptotagmin-11 (SYT11) protein may be involved in Ca2+-dependent exocytosis of secretory vesicles through Ca2+ and phospholipid binding to the C2 domain or may function as Ca2+ sensors in the process of vesicular trafficking and exocytosis.

Ras-related protein M-Ras (MRAS) is a member of the RAS superfamily. These family members are membrane-anchored, intracellular signal transducers in charge of various normal cellular functions. They are oncogenically stimulated in a substantial fraction of tumors. MRAS serves as a significant signal transducer for novel upstream stimuli in controlling cell proliferation.

Speckle-type POZ protein (SPOP) belongs to the Tdpoz family containing one N-terminal MATH (Meprin and TRAF homology) domain and one C-terminal BTB/POZ domain. SPOP inhibits IPF1/PDX1 transactivation of established target promoters, may be by recruiting a repressor complex. SPOP is involved in ubiquitinylation and protein degradation as a result of an interaction with CUL-3.

Clusterin also named Apolipoprotein J (APO-J) is a 75-80 kD disulfide-linked heterodimeric protein containing about 30% of N-linked carbohydrate rich in sialic acid but truncated forms targeted to the nucleus have also been identified.
The precursor polypeptide chain is cleaved proteolytically to remove the 22-mer secretory signal peptide and subsequently between residues 227/228 to generate the a and b chains. These are assembled in anti-parallel to give a heterodimeric molecule in which the cysteine-rich centers are linked by five disulfide bridges and are flanked by two predicted coiled-coil a-helices and three predicted amphipathic a-helices.
Across a broad range of species clusterin shows a high degree of sequence homology ranging from 70% to 80%. It is nearly ubiquitously expressed in most mammalian tissues and can be found in plasma, milk, urine, cerebrospinal fluid and semen.
It is able to bind and form complexes with numerous partners such as immunoglobulins, lipids, heparin, bacteria, complement components, paraoxonase, beta amyloid, leptin and others. Clusterin has been ascribed a plethora of functions such as phagocyte recruitment, aggregation induction, complement attack prevention, apoptosis inhibition, membrane remodeling, lipid transport, hormone transport and/or scavenging, matrix metalloproteinase inhibition.
A genuine function of clusterin has not been defined. One tempting hypothesis says that clusterin is an extracellular chaperone protecting cells from stress induced insults caused by degraded and misfolded protein precipitates.
Clusterin is up- or down regulated on the mRNA or protein level in many pathological and clinically relevant situations including cancer, organ regeneration, infection, Alzheimer disease, retinitis pigmentosa, myocardial infarction, renal tubular damage, autoimmunity and others.

Ras-related protein Ral-A (RALA) is a member of the small GTPase superfamily, Ras family of proteins. RALA mediates a distinct downstream signaling pathway from Ras which facilitates cellular transformation. Furthermore, RALA is thought to be involved in various signaling cascades, including regulation of the cytoskeleton, vesicle trafficking, and endocytosis.

N-myc-interactor belongs to the oncogene Myc family which has a significant part in cell proliferation, differentiation, and neoplastic transformation. In Addition, NMI cooperates with all STATs except STAT2 and augments STAT-mediated transcription in response to cytokines IL2 and IFN-gamma. The NMI mRNA is expressed in small quantities in all human fetal and adult tissues tested except brain and but in large quantities in cancer cell line-myeloid leukemias.

IHH belongs to the hedgehog family of secreted signaling molecules. Hedgehog proteins are vital regulators of various developmental processes including growth, patterning and morphogenesis. The vertebrate homologues of Hh comprise several proteins including sonic hedgehog (Shh), Indian hedgehog (Ihh), and Desert hedgehog (Dhh). IHH has a specific role in bone growth and differentiation. In addition, IHH is involved in yolk sac vasculogenesis, having a central role in differentiation of epiblast cells into endothelial and red blood cells. IHH mRNA expression is detected in fetal lung, gut, stomach, liver, kidney, pancreas and strongly in cartilage in growth regions of the developing bone. IHH gene mutations cause the brachydactyly type A1 which is characterized by shortening or malformation of the phalanges and also the acrocapitofemoral dysplasia.

MMP-1 (interstitial collagenase) can break down a wide range of substrates including types I, II, III, VII, VIII, and X collagens as well as L-Selectin, pro-TNF, IL-1?, IGFBP-3, IGFBP-5, casein, gelatin, ?1 antitrypsin, myelin basic protein, pro-MMP2 and pro-MMP9. A significant function of MMP-1 is the degradation of fibrillar collagens in extracellular matrix remodeling. MMP-1 is expressed in fibroblasts, keratinocytes, endothelial cells, monocytes and macrophages. MMP1 can be divided into a number of distinct domains: a prodomain which is cleaved on activation, a catalytic domain containing the zinc binding site and a short hinge region with a carboxyl terminal domain. MMP1 is part of a cluster of MMP genes which localize to chromosome 11q22.3.

Secreted frizzled-related protein 2 (SFRP2) belongs to the SFRP family which contains a cysteine-rich domain homologous to the putative Wnt-binding site of Frizzled proteins. SFRP2 functions as soluble modulators of Wnt signaling. Methylation of SFRP2 might indicate on colorectal cancer.

Osteostat is the cytokine that binds to TNFRSF18/AITR/GITR and is important for interactions between activated T-lymphocytes and endothelial cells and may modulate T-lymphocyte survival in peripheral tissues. Osteostat is expressed at high levels in the small intestine, ovary, testis, kidney and endothelial cells after stimulation by lipopolysaccharides.
Osteostat protein is detectable in human microvascular EC and is highly up-regulated by IFN-alpha and IFN-beta. Osteostat inhibit differentiation of osteoclasts from monocytic precursor cells. Osteostat suppresses the early stage of osteoclastogenesis via inhibition of macrophage colony-stimulating factorinduced receptor activator of NF-kappaB (RANK) expression in the osteoclast precursor cells. Osteostat does not inhibit lipopolysaccharide-induced RANK expression in monocytes and dendritic cells, or activation-induced RANK expression in T cells. Osteostat is a novel regulator of osteoclast generation and substantiate the major role played by the endothelium in bone physiology.

ARL2 is a member of the ADP-ribosylation factor (ARF) family. ARL2 functions as a component of a secretory pathway which is involved in the Ca2-dependent release of acetylcholine. ARL2 has a role in the folding of tubule proteins, thus playing a significant role in microtubule dynamics and cell cycle progression. Unlike other members of the ARF family, ARL2 doesn’t act as an activator of the catalytic subunit of cholera toxin.

CKS1B protein which binds to the catalytic subunit of cyclin dependent kinases is vital for their biological function. The CKS1B mRNA is expressed in HeLa cells during the course of cell cycle in several forms which suggests that the encoded protein has a particular function. Two transcript variants were identified for this gene however it seems that only one of them encodes a protein.

Platelet factor-4 is a 70-amino acid protein that is released from the alpha-granules of activated platelets and binds with high affinity to heparin. Its major physiologic role appears to be neutralization of heparin-like molecules on the endothelial surface of blood vessels, thereby inhibiting local antithrombin III activity and promoting coagulation. As a strong chemoattractant for neutrophils and fibroblasts, PF4 probably has a role in inflammation and wound repair. Oncostatin-A is a member of the CXC chemokine family. Human PF4 is used for the proof of heparin-induced thrombocytopenia. Furthermore it is used as an inhibitor in the angiogenesis during tumor therapy.

RAP1B is a member of a superfamily of RAS-like small GTP-binding proteins which takes part in cell signaling. RAP1B owns an intrinsic GTPase activity and is universally expressed in mammalian tissues. The alleged effector domain of Ras proteins, whose integrity is required for cell transformation as well as interaction with the putative effector protein GAP, is conserved in both Rap 1 proteins.

RAB8, Member RAS Oncogene Family (RAB8B), is a low molecular mass monomeric GTPases which localize on the cytoplasmic surfaces of distinct membrane-bound organelles. RAB8 takes part in polarized vesicular trafficking and neurotransmitter release and also in cell junction dynamics in Sertoli cells. RAB proteins function in intracellular vesicle transport by aiding in the docking or fusion of vesicles with their target membranes.

E3 ubiquitin-protein ligase RNF181 (RNF181) accepts ubiquitin from an E2 ubiquitin-conjugating enzyme in the thioester form and subsequently directly transfers the ubiquitin to targeted substrates. RNF181 is widely expressed, with the highest levels in the liver and heart and the lowest levels in the brain and skeletal muscle. RNF181 is also expressed in platelets (at protein level).

Sorting nexin 3 (SNX3) belongs to the large family of hydrophilic proteins, which interact with various receptor types and are involved in intracellular trafficking. SNX3 interacts with phosphatidylinositol-3-phosphate, and is involved in protein trafficking. SNX3 comprises a distinct subgroup of nexins, which share less sequence similarity outside of the PX domain and have significantly different binding affinities for the tyrosine kinase receptors.

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.

GroEL, HSP60 is a chaperonin located in the mitochondria which is responsible for the transportation & refolding of proteins from the cytoplasm directly into the mitochondrial matrix. GroEL is regulated by the HSP10 cochaperonin, which is a single heptameric protein ring having a molecular mass of 10 kDa which form a unique complex with HSP60. HSP10, GroES coordinates the ATPase activity of the HSP60 subunits in order to allow the release of bound polypeptide in a manner that is productive for its correct folding.