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15 KDa Selenoprotein (SEP15) is a protein-coding gene which contains a selenocysteine (Sec) residue at its active site. Theselenocysteine is encoded by the UGA codon that usually signals translation termination. The 3' UTR ofselenoprotein genes have a conventional stem-loop structure, the sec insertion sequence (SECIS), which isnecessary for the recognition of UGA as a Sec codon rather than as a stop signal. Studies in mouse propose thatthis selenoprotein may have redox function and may be implicated in the quality control of protein folding. This geneis localized on chromosome 1p31, a genetic locus usually mutated or deleted in human cancers.Diseases associated with SEP15 include lung cancer susceptibility, and chronic lymphocytic leukemia.

HMGB1 is an abundant chromatin-binding protein found in eukaryotic cell nucleus and acts in the assembly of nucleoprotein complexes. Inside the cell, HMGB1 binds to DNA and is involved in transcriptional regulation. Outside the cell, HMGB1 acts as a cytokine with activities that resemble those of tumor necrosis factor (TNF). HMGB1 is elevated significantly in chronic kidney disease patients and correlates with glomerular filtration rate as well as with markers of inflammation and malnutrition. HMGB1 is involved in Gram-negative sepsis by catalyzing movement of LPS monomers from LPS aggregates to CD14 to initiate a TLR4-mediated proinflammatory response. HMGB1 plays an important role in the relationship between necrosis and malignancy in glioma tumours. HMG1 protein is induced by Mycobacterium bovis BCG. Overexpression of HMGB1 is common in gastrointestinal stromal tumors and is related to the KIT mutation. HMG1 induces growth inhibition and apoptosis in macrophages through RAGE intracellular signaling pathway. The increase of extracellular HMGB1 observed in salivary glands of Sjogren's syndrome patients indicates that HMGB-1 is involved in the inflammatory process of the disease. HMGB-1 together with estrogen increase cell cycle progression in tumor cell lines.

HMGB2 belongs to the non-histone chromosomal high-mobility group protein family which are chromatin-associated and highly spread in the nucleus of higher eukaryotic cells. HMGB2 can successfully bend DNA and form DNA circles which indicates that HMGB2 facilitates cooperative interactions between cis-acting proteins by promoting DNA flexibility. Additionally, HMGB2 takes part in the final ligation step in DNA end-joining processes of DNA double-strand breaks repair and V(D)J recombination.

HRSP12 (UK114) is an endoribonuclease found mainly in the human adult kidney and liver, and which is responsible for inhibiting translation by cleaving mRNA. HRSP12 cleaves phosphodiester bonds only in single-stranded RNA. HRSP12 may be an important biomarker for heptatic carcinoma.

DR1 is a phosphoprotein that inhibits both basal and activated levels of transcription. DR1 is phosphorylated in vivo which affects its interaction with TBP. DR1 has a histone fold motif at the amino terminus, a TBP-binding domain, and a glutamine- and alanine-rich region. By selectively repressing polymerases II and III, DR1 alters the physiological balance of transcriptional output in favor of polymerase I.

A natural cytotoxicity receptor (NCR) NKp46 has been shown to represent a novel NK cell-specific molecule involved in human NK cell activation. The natural cytotoxicity receptors (NCRs) are a recently characterized family of Ig-like activation receptors that appear to be major triggering receptors in tumor cell recognition. The three known NCRs include NKp46 and NKp30, which are expressed on circulating NKcells, and NKp44, which is expressed only on activating NK cells. NKp46 has been implicated in NK cell-mediated lysis of several autologous tumor cells, pathogen-infected cell lines and mononuclear phagocytes infected with an intracellular bacterium. The Lysis of tumor cells by NK-cells involves recognition by NKp46 of heparan sulfate moieties of membrane heparan sulfate proteoglycans. Furthermore, NKp46 is a surface receptor involved in NK-cell cell death by apoptosis. NKp46 has two extracellular Ig-like domains followed by a ~40 residue stalk region, a type I transmembrane domain, and a short cytoplasmic tail. The extracellular Ig-like domain of NKp46 (22-255aa) is purified by FPLC gel-filtration chromatography, after refolding of the isolated inclusion bodies in a redox buffer. In addition, engagement of the antigen with the monoclonal antibody stimulates intracellular calcium levels and the synthesis of cytokines. CD59 is an NKp46 coreceptor (by physical association) together they activate cytotoxicity of human NK-cells, their engagement results in tyrosine phosphorylation of CD3-zeta chains associated with NKp46. Reduced cell surface expression of NKp46 and other NK-cell receptors is linked to the impaired NK-cell cytolytic function in viremic HIV-1 infection.

ATPase inhibitory factor 1 (ATPIF1) attaches to the C-terminal region of a beta subunit of the F1-ATPase at low pH values and, through interference of the beta and gamma subunit interaction, ATPIF1 controls the activity of the F1 (the hydrophilic catalytic core), F0 (the membrane embedded protein channel) ATPase. ATPIF1 overexpression in a number of human carcinomas additionally reinforces its participation in oncogenesis and offers insight into the transformed metabolism of cancer cells, including the reprogramming of energy metabolism in relation to glycolysis. Endogenous F1F(o)-ATPase inhibitor curbing ATP depletion when the mitochondrial membrane potential drops below a threshold and the F1F(o)-ATP synthase begins hydrolyzing ATP to pump protons out of the mitochondrial matrix.

BCA-1 is a CXC chemokine that is highly expressed in thesecondary lymphoid organs, such as follicles of the spleen, lymph nodes, and Peyer's patches. CXCL13 promotes the migration of B lymphocytes (compared to T cells and macrophages), by stimulating calcium influx into, and chemotaxis of, cells expressing Burkitt's lymphoma receptor 1 (BLR1). BCA1 therefore function in the homing of B lymphocytes to follicles. Human BCA-1 shares a 64% amino acid sequence similarity with the mouse protein and 23 - 34% amino acid sequence identity with other known CXC chemokines. Recombinant or chemically synthesized BCA1 is a potent chemoattractant for B lymphocytes but not T lymphocytes, monocytes or neutrophils. BLR1, a G protein-coupled receptor originally isolated from Burkitt’s lymphoma cells, has now been shown to be the specific receptor for BCA1. Among cells of the hematopoietic lineages, the expression of BLR-1, now designated CXCR-5, is restricted to B lymphocytes and a subpopulation of T helper memory cells.

Cytosolic Fe-S cluster assembly factor NUBP1 isoform 1 (NUBP1) is Involved in the regulation of centrosome duplication similarity. NUBP1 is a component of the cytosolic iron-sulfur (Fe/S) protein assembly (CIA) machinery. NUBP1 is necessary for maturation of extra mitochondrial Fe-S proteins. The NUBP1-NUBP2 heterotetramer constructs a Fe-S scaffold complex, mediating the de novo compilation of a Fe-S cluster and its transfer to target apoproteins.

Elcatonin is a Calcitonin derivative which is transformed from eel´s calcitonin by changing the S-S bond into the stable C-N bond. It inhibits the absorption and autolysis of bones, thus leads to blood calcium descending. In addition, it inhibits the bone salts dissolving and transferring and promotes the excretion of calcium and phosphorus in urine. Meanwhile, it inhibits renal tubules reabsorbing calcium, phosphorus and sodium and keeps blood calcium at normal level. It is mainly used for remitting or eliminating the pain caused by Osteoporosis.

SRGN is identified as a hematopoietic cell granule proteoglycan. Proteoglycans stored in the secretory granules of various hematopoietic cells also hold a protease-resistant peptide core, and is vital for neutralizing hydrolytic enzymes. SRGN is related to the macromolecular complex of granzymes and perforin that acts as a intermediary of granule-mediated apoptosis.

Olfactory marker protein (OMP) which is expressed in the cytoplasm of olfactory chemosensory neurons in the nasal neuroepithelium, is associated in a unique way with the mature olfactory receptor neurons in numerous vertebrate species. OMP have a modulatory part in the odor detection/signal transduction cascade ant its expression is a sign of mature vertebrate olfactory receptor neurons (ORNs). OMP is also a potent enhancer of mitosis in fetal olfactory epithelial cells and it promotes an increase in uptake of tritiated thymidine in liver.

EPHB4 or Ephrin type-B receptor 4 is encoded by the EPHB4 gene in humans. The receptor and its ligands (the ephrins) take part in different developmental stages, mainly in the nervous system. EPHB4 and other Ephrin receptors are the biggest subgroup of the RTK receptors. EPHB4 binds to ephrin B2 and has a crucial part in the development of the vascular system.

Streptavidin is a tetrameric protein secreted by Streptomyces avidinii which binds firmly to biotin. Streptavidin is widely used in molecular biology through its unique high affinity for the vitamin biotin. The dissociation constant (Kd) of the biotin-streptavidin complex is about ~10-15 mol/L. The strong affinity recognition of biotin and biotinylated molecules has made streptavidin one of the most important components in diagnostics and laboratory kits. The streptavidin/biotin system has one of the biggest free energies of association of yet observed for noncovalent binding of a protein and small ligand in aqueous solution (K_assoc = 10**14). The complexes are also extremely stable over a wide range of temperature and pH.

CACYBP (calcyclin binding protein) participates in calcium-dependent ubiquitination and subsequent proteosomal degradation of target proteins. CACYBP acts as a molecular bridge in ubiquitin E3 complexes. CACYBP is involved in the ubiquitin-mediated degradation of beta-catenin.

Calretinin is an intracellular calcium-binding protein belonging to the troponin C superfamily characterized by a structural motif described as the EF-hand domain. The immunohistochemical detection of calretinin in developing cerebellum is restricted to the later stages indicated by weak staining from week 21 of gestation, in Purkinje and basket cells and in neurons of the dentate nucleus. The intensity of staining increases as the cerebellum matures. In tumors, calretinin has been detected in mesotheliomas and some pulmonary adenocarcinomas.

Transferrin receptor protein 1 (TFRC) is required for iron delivery from transferring to cells. The TFRC protein is a transmembrane glycoprotein comprised of 2 disulfide-linked monomers joined by 2 disulfide bonds. Each monomer will bind one holo-transferrin molecule producing an iron-Tf-TfR complex which enters the cell by endocytosis.

FHIT enzyme cleaves adenosine 5'' PPP 5'' A to yield AMP and ADP. FHIT gene includees the regular fragile site FRA3B on chromosome 3. Alterations and deletions of the FHIT gene are highly linked to the genesis and establishment of human tumors of the lung, cervix, breast, colon, stomach and pancreas. In normal cells, FHIT functions as a tumor suppressor and physically relates with ubiquitin conjugating enzyme 9.

CASQ2 belongs to the calsequestrin family and is localized to the sarcoplasmic reticulum in cardiac and slow skeletal muscle cells. CASQ2 is a calcium binding protein that stores calcium for muscle function. The discharge of calcium bound to CASQ2 through a calcium release channel activates muscle contraction. CASQ2 binds 40 to 50 moles of calcium. CASQ2 mutations result in stress-induced polymorphic ventricular tachycardia, also called catecholaminergic polymorphic ventricular tachycardia 2 which is known fir its bidirectional ventricular tachycardia that causes cardiac arrest.

Inhibitor of Growth Family Member 1, also known as ING1 is a tumor suppressor protein which is able to induce cell growth arrest and apoptosis. ING1 is a nuclear protein which physically act together with the tumor suppressor protein TP53 and is a component of the p53 signaling pathway. In addition, Reduced expression and rearrangement of ING1 have been identified in various cancers. Multiple alternatively spliced transcript variants encoding distinct isoforms have been described for ING1.

Human CCL16, also called HCC-4, liver-expressed chemokine (LEC), and lymphocyte and monocyte chemoattractant (LMC), is a novel CC chemokine recognized by bioinformatics. NCC-4 cDNA encodes a 120 amino acids along with a 23 amino acids signal peptide that is cleaved to generate 97 amino acid protein. HCC4 is vaguely related to other CC chemokines, showing less than 30% sequence identity. Among CC chemokines, CCL-16 has the largest similarity to HCC-1. 2 potential polyadenylation signals are present on the human HCC-4 gene, and as a result, 2 transcripts containing roughly 1,500 base pairs and 500 base pairs have been detected. HCC-4 is expressed weakly by some lymphocytes, including NK cells, T cells, and some T cell clones. The expression of HCC-4 in monocytes is greatly upregulated in the presence of IL-10.
CCL16 shows chemotactic activity for lymphocytes and monocytes rather than to neutrophils. NCC-4 has potent myelosuppressive activity, suppresses proliferation of myeloid progenitor cells. CCL16 demonstrates chemotactic activity for monocytes and thp-1 monocytes, rather than for resting lymphocytes and neutrophils. HCC-4 induces a calcium flux in thp-1 cells that desensitized prior to the expression of rantes.

GH is a member of the somatotropin/prolactin family of hormones which play an important role in growth control. The gene, along with four other related genes, is located at the growth hormone locus on chromosome 17 where they are interspersed in the same transcriptional orientation; an arrangement which is thought to have evolved by a series of gene duplications. The five genes share a remarkably high degree of sequence identity. Alternative splicing generates additional isoforms of each of the five growth hormones, leading to further diversity and potential for specialization. This particular family member is expressed in the pituitary but not in placental tissue as is the case for the other four genes in the growth hormone locus. Mutations in or deletions of the gene lead to growth hormone deficiency and short stature.

PRDX2 is part of the peroxiredoxin family of antioxidant enzymes, which reduce hydrogen peroxide and alkyl hydroperoxides. PRDX2 takes part as an antioxidant protective role in cells, and contributes to the antiviral activity of CD8(+) T-cells. PRDX2 has proliferative effect in cancer development or progression.
If PRDX2 protection is insufficient against peroxidases, the DNA damage results in neurological disease such as Alzheimer's or DNA damage leading to cancer.

Peroxiredoxin 6 (PRDX6) belongs to the thiol-specific antioxidant protein family. PRDX6 is a bifunctional enzyme with 2 distinct active sites. PRDX6 is involved in redox regulation of the cell and can reduce Hydrogen peroxide and short chain organic, fatty acid, and phospholipid hydroperoxides. PRDX6 may have a role in the regulation of phospholipid turnover as well as in protection against oxidative injury. Furthermore, PRDX6 eases the oxidative stress and TGF-beta-induced abnormalities of human trabecular meshwork cells. In addition, PRDX6 is necessary for blood vessel integrity in injured skin.
At acidic pH, PRDX6 binds to reduced phospholipids, however at cytosolic pH PRDX6 binds only to phospholipids that are oxidized which is compatible with the role for PRDX6 in the repair of peroxidized cell membranes. Hydrogen peroxide-mediated hyperoxidation of PRDX6 induces cell cycle arrest at the G2/M transition via up-regulation of iPLA2 activity. Overexpression of PRDX6 is linked to oligodendroglioma.