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COP9 Constitutive Photomorphogenic 6 (COPS6) is a member of the translation initiation factor 3 (eIF3) superfamily,peptidase M67A family and CSN6 subfamily. COPS6 is one of 8 subunits of COP9 signalosome,a highly conserved protein complex which functions as an significant regulator in multiple signaling pathways. COP9's structure and function of signalosome is similar to 19S regulatory particle of 26S proteasome. COP9 signalosome can interact with SCF-type E3 ubiquitin ligases and act as a positive regulator of E3 ubiquitin ligases.COP9 takes part in the regulation of cell cycle and likely to be a cellular cofactor for HIV-1 accessory gene product Vpr.

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. RPL34 is a member of the L34E family of ribosomal proteins and it encodes a ribosomal protein which is a component of the 60S subunit. RPL34 is found in the cytoplasm and has been mapped to 4q though it was initially believed it is located at 17q21. Transcript variants which are a result of alternative splicing, alternative transcription initiation sites, and/or alternative polyadenylation exist; all encode the same protein. As is typical for genes encoding ribosomal proteins, there are several processed pseudogenes of this gene spread all over the genome.

Pollen allergen Phl p 6 (PhI p 6) causes an allergic reaction in humans.

Epiregulin is part of the EGF family. Epiregulin functions as a ligand of EGFR, as well as a ligand of most members of the ERBB (v-erb-b2 oncogene homolog) family of tyrosine-kinase receptors.Epiregulin is expressed mostly in the placenta and peripheral blood leukocytes and in specific carcinomas of the bladder, lung, kidney and colon. Epiregulin stimulates the proliferation of keratinocytes, hepatocytes, fibroblasts and vascular smooth muscle cells. Epiregulin inhibits the growth of several tumor-derived epithelial cell lines. Human Epiregulin is initially synthesized as a glycosylated 19.0 kDa transmembrane precursor protein, which is processed by proteolytic cleavage to produce a 6.0 kDa mature secreted sequence.

Recombinant Hirudin is a potent thrombin inhibitor originally derived from the medicinal leech. Hirudin acts directly on thrombin rather than through other clotting factors. The mechanism of Hirudin-thrombin appears to be unique. The conversion of fibrinogen into fibrin by the serine protease enzyme thrombin is a major event in the final stages of blood coagulation. In the final stages of coagulation prothrombinase converts prothrombin into thrombin. Fibrin is subsequently cross linked by factor XIII to form a blood clot. The primary inhibitor of thrombin in normal blood circulation is antithrombin III. The anticoagulatant activity of hirudin is derived from its ability to inhibit the pro-coagulant activity of thrombin (similar to antithrombin III activity). Hirudin is the strongest natural inhibitor of thrombin. Hirudin binds to and inhibits only the activity of thrombin forms with a specific activity on fibrinogen contrasting to antithrombin III activity. Therefore, hirudin has a thrombolytic activity since it prevents or dissolves the formation of clots and thrombi. Hirudin also has therapeutic significance in blood coagulation disorders, in the treatment of skin hematomas and of superficial varicose veins. Hirudin does not hinder with the biological activity of other serum proteins and can also act on complexed thrombin, thus having an advantage over more common anticoagulants and thrombolytics. It is complicated to extract large quantities of hirudin from natural sources; therefore a method for producing and purifying hirudin using recombinant biotechnology has been developed.

Resistin, a product of the RSTN gene, is a peptide hormone belonging to the class of cysteine-rich secreted proteins (monomeric peptide contains 11 cysteine residues) referred to as the RELM family, and is also described as ADSF (Adipose Tissue-Specific Secretory Factor) or FIZZ3 (Found in Inflammatory Zone 3). Mouse resistin is expressed as a 114 amino acid prepeptide; its hydrofobic Nterminal 20 amino acid signal peptide is cleaved before its secretion. Mouse resistin circulates in blood as a homodimeric protein consisting of two 94 amino acid polypeptides, which are disulfide-linked via Cys26.
Resistin may be an important link between obesity. Mouse resistin, specifically produced and secreted by adipocyte, acts on skeletal muscle myocytes, hepatocytes and adipocytes themselves so that it reduces their sensitivity. Steppan et al. have suggested that resistin suppressed the ability to stimulate glucose uptake. They have also suggested that resistin was present at elevated levels in blood of obese mice, and was down regulated by fasting and by antidiabetic drugs. Way et al., on the other hand, have found that resistin expression is severely suppressed in obesity.
Other studies have shown that mouse resistin increases during the differentiation of adipocytes, but it also seems to inhibit adipogenesis. In contrast, the human adipogenic differentiation is likely to be associated with a down regulation of resistin gene expression.

Proprotein Convertase Subtilisin/Kexin Type 1 Inhibitor (PCSK1N) takes part in the control of the neuroendocrine secretory pathway. PCSK1N inhibits prohormone convertase 1, which regulates the proteolytic cleavage of neuroendocrine peptide precursors. PCSK1Nslows down convertase-mediated processing of proopiomelanocortin and proenkephalin and also monitors the intracellular timing of PCSK1.

Peptidyl-prolyl cis-trans isomerase-like 3 (PPIL3) belongs to the cyclophilin family which catalyzes the cis-trans isomerization of peptidylprolyl imide bonds in oligopeptides. PPIL3 acts either as catalyst or as molecular chaperone in protein-folding events.

Transferrin is the iron-transport protein of vertebrate serum and donates iron to cells through interaction with a specific membrane receptor, CD71. Transferrin appears to be indispensable for most cells growing in tissue culture.
It is referred to frequently as a growth factor because, in analogy to other growth factor-receptor interactions, proliferating cells express high numbers of transferrin receptors, and the binding of transferrin to their receptors is needed for cells to initiate and maintain their DNA synthesis. Apart from its role as an iron transport protein transferrin acts as a cytokine and has functions that may not be related to its iron-carrying capacity.

Art v 1, Artemisia vulgaris (mugwort) is a common weed in the Mediterranean area. The significant allergen of mugwort pollen, is a secreted modular glycoprotein with a N-terminal defensin-like and a C-terminal hydroxyproline-rich domain. The reactivity of IgE antibodies is primarily aimed to epitopes located in the N-terminal domain.

The Melanoma Inhibitory protein (MIA) was identified as an inhibitor of in vitro growth of malignant melanoma cells. The protein contains a SH3 domain. MIA acts as a potent tumor cell growth inhibitor for malignant melanoma cells and some other neuroectodermal tumors, including gliomas, in an autocrine fashion. In a study of human melanoma cell lines with different metastatic capacity MIA mRNA expression appeared to be inversely correlated with pigmentation. MIA has been shown to represent a very sensitive and specific serum marker for systemic malignant melanoma that might be useful for staging of primary melanomas, detection of progression from localized to metastatic disease during follow-up, and monitoring therapy of advanced melanomas.

Beta Defensin 118 (DEFB118) which is a member of the beta subfamily of defensins, is found in a cluster with other beta-defensin genes on the long arm of chromosome 20. Beta-defensins are antimicrobial peptides which provide protection for tissues and organs from infection by a diversity of microorganisms. DEFB118 protein’s expression is regulated by androgen, and the encoded protein binds to sperm and exhibits antibacterial activity.

Charged multivesicular body protein 3 (VPS24/CHMP3) is a member of the vacuolar sorting protein family and function as chromatin modifying proteins. VPS24 links directly with CHMP2 and CHMP4 for the disassembly of ESCRT-III complex in an ATP-dependent manner. During HIV-1 infection, the virus uses the ESCRT-III complex to mediate budding and exocytosis of viral proteins. VPS24 overexpression strongly hinders HIV-1 release.

Adiponectin is a hormone exclusively expressed from adipose tissue.
Many studies demonstrate that Adiponectin has direct anti-diabetic, anti-atherogenic and anti-inflammatory functions. APM-1 can increase insulin sensitivity of skeletal muscle. Attenuate hepatic lipogenesis and gluconeogenesis, regulate NO production in endothelial cells, inhibit proliferation of smooth muscle cells and prevent lipid accumulation of macrophage cells.
In the circulation, Adiponectin is present as three different oligomeric complexes, including the high molecular weight (HMW), the middle molecular weight (MMW, also called hexamer) and low molecular weigh (MMW, also called trimer) forms 8. Different oligomeric complex of Adiponectin activates different signaling pathways and exerts distinct functions.

Sonic Hedgehog is part of a small group of secreted proteins which are vital for development in both vertebrates and invertebrates. 3 mammalian hedgehog genes (sonic, desert, Indian) share about 60% homology. The Human Sonic Hedgehog is 99% homologous to the mouse gene. Sonic HedgeHog is a protein that is vital in guding the early embryo. It has been associated as the major inductive signal in patterning of the ventral neural tube, the anterior-posterior limb axis, and the ventral somites. Sonic HedgeHog binds to the patched receptor, which functions in association with smoothened, to activate the transcription of target genes. In the absence of sonic HedgeHog, patched receptor represses the constitutive signaling activity of smoothened. Sonic HedgeHog also regulates another factor, the gli oncogene. Sonic HedgeHog intercellular signal is essential for a various patterning events during development: signal produced by the notochord that induces ventral cell fate in the neural tube and somites, and the polarizing signal for patterning of the anterior-posterior axis of the developing limb bud. Sonic HedgeHog exhibits both floor plate- and motor neuron-inducing activity. Mutations in a long-range Sonic HedgeHog enhancer located in an intron of the limb region 1 gene result in preaxial polydactyly.

Transmembrane protein PRRT2 holds a proline-rich domain in its N-terminal half. PRRT2 is known to be primarily expressed in brain and spinal cord in embryonic and postnatal stages. Alterations in this gene are the cause for paroxysmal kinesigenic dyskinesia. PRRT2 mutations were found in nearly 30% of sporadic PKC patients.

Plasma protease C1 inhibitor (SERPING1) is a part of the serpin superfamily of serine protease inhibitors. SERPING1 plays an important role in regulating activation of both the complement and contact systems. That isdue to the fact that SERPING1 regulates the activation of complement factor C1 in addition to the activity of activated C1 by coupling with the active catalytic site at the light chains of C1r and C1s. SERPING1 insufficiency results in hereditary angioedema, which is characterized by recurrent episodes of localized angioedema of the skin, gastrointestinal mucosa or upper respiratory mucosa.

Eotaxin-2, also called MPIF2 & Ckb6, is a novel CC chemokine produced by activated monocytes and T lymphocytes. Eotaxin-2 selectively chemoattracts cells expressing CCR3 including eosinophils, basophils, Th2 T cells, mast cells, and certain subsets of dendritic cells. Furthermore, Eotaxin-2 inhibits the proliferation of multipotential hematopoietic progenitor cells. The mature protein, which includes C-terminal truncation, contains 78 amino acids (92 amino acids for the mouse homolog, without C-terminal truncation).
CCL24 functions as a chemotactic chemokine for resting t-lymphocytes, and eosinophils. CCL24 has lower chemotactic activity for neutrophils but none for monocytes and activated lymphocytes. CCL24 is a strong suppressor of colony formation by a multipotential hematopoietic progenitor cell line and binds to CCR3.

PMF1-BGLAP is a locus which represents naturally occurring read-through transcription between the neighboring polyamine-modulated factor 1 (PMF1) and bone gamma-carboxyglutamate Gla protein (BGLAP) genes on chromosome 1. There are multiple transcript variants encoding isoforms as a results of alternative splicing which share sequence identity with the upstream gene product, but they have a different C-termini because of frameshifts as opposed to the downstream gene coding sequence.

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.

Flagellin FliA (H), also known as RNA polymerase sigma factor for flagellar operon, Sigma F and Sigma-28, is a part of the FliA subfamily or sigma-70 factor family. This sigma factor controls the expression of flagella-related genes. Flagellin FliA (H) regulates the expression of genes involved in virulence. Flagellin FliA (H) is an initiation factors which endorses the attachment of RNA polymerase to specific initiation sites and are then released.

Keratin 8 and 18 (K8/18) are the major components of intermediate filament (IF) proteins of simple or single-layered epithelia.

PRND is a membrane glycosylphosphatidylinositol-anchored glycoprotein which exists mainly in testis. PRND is expressed during embryogenesis, although in the central nervous system it is expressed minimally .Mutations in PRND may cause neurological disorders. PRND located on chromosome 20, about 20 kbp downstream of the gene encoding cellular prion protein, to which it is biochemically and structurally analogous.