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Cystatin-A is the intracellular inhibitor of cysteine proteinase cathepsin B (CatB) and belongs to family 1 of the cystatin superfamily of inhibitor proteins. CSTA is a stefin that functions as a cysteine protease inhibitor, forming tight complexes with papain and the cathepsins B, H, and L. It has been proposed that extracellular CatB together with other classes of proteinases are all subjected to a cascade-like manner of activation. CatB and its inhibitor Cystatin-A are involved in degradation of extracellular matrix proteins during tissue remodeling. CSTA is one of the precursor proteins of cornified cell envelope in keratinocytes and plays a role in epidermal development and maintenance. Cystatin-A has been reported to be found in high concentrations in epithelial cells, polymorphonuclear leukocytes and lymphoid tissue. Stefins may be used as prognostic and diagnostic tools for cancer.

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.

SIRT6 is part of the sirtuin family of proteins (Class IV), homologs to the yeast Sir2 protein. SIRT6 is characterized by a sirtuin core domain. Yeast sirtuin proteins are recognized by their ability to regulate epigenetic gene silencing and suppress recombination of rDNA. SIRT6, a chromatin-associated protein is involved in DNA repair. Human Sirtuins function as intracellular regulatory proteins with mono-ADP-ribosyltransferase activity.

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.

APIP catalyzes the dehydration of methylthioribulose-1-phosphate (MTRu-1-P) into 2,3-diketo-5-methylthiopentyl-1-phosphate (DK-MTP-1-P). APIP has an anti-apoptotic function and inhibits muscle ischemic impairment. APIP inhibits the cytochrome c-dependent and APAF1-mediated cell death.

CMV belongs to the Betaherpesvirinae subfamily of Herpesviridae which includes herpes simplex virustypes 1 and 2, varicella-zoster virus, and Epstein-Barrvirus. The herpesviruses share a characteristic ability to remain latentover long periods. CMV is a double-stranded linear DNA virus with 162 hexagonal protein capsomeres surrounded by a lipid membrane. CMV has the largest genome of the herpes viruses, ranging from 230-240 kilobase pairs. Human CMV is composed of unique and inverted repeats that include the existence of 4 genome isomers caused by inversion of L-S genome components (class E). Replication may be divided into immediate early, delayed early, and late gene expression based on time of synthesis after infection. The DNA is replicated by rolling circles. In vitro, CMV replicates in human fibroblasts.

Sorcin (SRI) which is a 22kDa calcium-binding protein was originally identified in multidrug-resistant cells. Sorcin, which modulates excitation-contraction coupling in the heart, contributes to calcium homeostasis in the heart sarcoplasmic reticulum.

VAMP8 also called endobrevin, is the main component of a SNARE complex involved in the docking and fusion of synaptic vesicles with the presynaptic membrane. VAMP8 protein is involved in the regulatation of enzyme secretion in pancreatic acinar cells and plays a part in the abscission of the midbody during cell division, which leads to completely separate daughter cells. VAMP8 is essential for dense-granule secretion in platelets. VAMP8 is related with the perinuclear vesicular structures of the early endocytic compartment. VAMP8 interacts particularly with the soluble NSF-attachment protein (alpha-SNAP), through an VAMP8-containing SNARE complex.

Leucine Rich Repeat And Ig Domain Containing 1, also known as Lingo1 is primarily expressed in neuronal tissue, and most abundantly in the cortex. In addition, Lingo 1 is involved in the inhibition of axon regeneration all the way through a ternary complex formed with NgR1 (ligand-binding subunit) and p75 (signal transducing subunit). The inhibitory action is accomplished through RhoA-GTP upregulation in response to the presence of MOG, MAG or Nogo-66 in the central nervous system. Furthermore, LINGO-1 inhibits oligodendrocyte precursor differentiation as well as myelination, by a mechanism which also involves activation of RhoA, however it appears that it does not require 75 or NgR1.

Kelch Domain Containing 8B, also known as KLHDC8B shapes a distinct beta-propeller protein structure of kelch domains which allow for protein-protein interactions. In addition,mutations in KLHDC8B have been connected with Hodgkin lymphoma.

CXCL14 is involved in immunoregulatory and inflammatory processes. BRAK protein is structurally related to the CXC (Cys-X-Cys) subfamily of cytokines. CXCL14 displays chemotactic activity for monocytes but not for lymphocytes, dendritic cells, neutrophils or macrophages. CXCL14 is involved in the homeostasis of monocyte-derived macrophages.

ABRACL is a member of the costars family, ABRACL belongs to a new family of low molecularweight proteins, which is presented only in eukaryotes, and is absent in fungi.ABRA C-terminal like is a protein-coding gene.

C3d is derived from human C3 after a series of proteolytic cleavages.C3d is prepared from purified human C3. The C3 is converted to C3b by treatment with the natural human C3 convertase and this C3b is converted to iC3b. Finally, this iC3b is cleaved with trypsin to yield C3d.If the C3b precursor was attached to a surface (as occurs during complement activation) the iC3b, C3dg and C3d fragments would remain covalently attached to that surface.C3d is able to attach to a surfaceonly during complement activation on a surface. Surface-bound C3d is linked to the target through an ester or an amide covalent bond. Ester bonds are unstable, thusC3d releasesfrom the particle.

Chromgranin-A is part of the neuroendocrine secretory protein family. CHGA is located in secretory vesicles of neurons and endocrine cells. Chromgranin-A is a precursor to three biologically active peptides; vasostatin, pancreastatin, and parastatin. These peptides act as autocrine or paracrine negative modulators of the neuroendocrine system. Other peptides, including chromostatin, beta-granin, WE-14 and GE-25, are also derived from the full-length protein. Chromgranin-A has numerous biological activities on some tissues and organs and exerts a large spectrum of homeostatic actions, including antifungal and antimicrobial effect, modulation of cell adhesion, and inhibition of parathyroid hormone secretion.

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.

Drosophila that have mutations in their MAGOH gene produce progeny with defects in germplasm assembly and germline development. MAGOH, the human homolog of Drosophila mago nashi, is necessary for embryo development. In mammals, mRNA expression is not limited to the germ plasm, but is expressed ubiquitously in adult tissues and is induced by serum stimulation of quiescent fibroblast.

HSP104 is a molecular chaperone required for stress tolerance and for maintenance of [psi(+)] prions in the budding yeast Saccharomyces cerevisiae. Hsp104 can protect yeast cells against high temperature and high concentration of ethanol but mutation studies have shown this protein is not required for normal growth. Hsp104 was cloned into an E. coli expression vector and was purified to apparent homogeneity by using conventional column chromatography techniques.

Phosphoglycerate kinase 1, also referred to PGK1, is an X-linked enzyme whichfunctions in the glycolytic pathway.The gene encoding the erythrocyte enzyme PGK1 & it seems that PGK-1 plays a role as a polymerase alpha cofactor protein (primer recognition protein) as a glyxolytic enzyme role. The PGK1 catalyzes the reversible conversion of 1, 3-diphosphoglycerate to 3-phosphoglycerate during glycolysis, generating one molecule of ATP.

POU2AF1 is a lymphocyte specific transcription coactivator protein. POU2AF1 cooperates only with the Oct1/2 proteins using sub domains in the POU domain of the Oct1/2 proteins, increasing their transcriptional efficiency. Even though POU2AF1 have no basic ability to bind DNA, it links firmly with the octomer motif in the presence of Oct1 and Oct2. POU2AF1 is expressed at maximum levels in spleen and peripheral blood leukocytes.

Marginal zone B- and B1-cell-specific protein (MZB1) functions as a hormone-regulated adipokine/proinflammatory cytokine which is implicated in causing chronic inflammation and affecting cellular expansion. MZB1 links with immunoglobulin M (IgM) heavy and light chains and stimulate s IgM assembly and secretion. MZB1 exerts its effect by acting as a molecular chaperone or as an oxidoreductase as it exhibits a low level of oxidoreductase activity. MZB1 helps to diversify peripheral B-cell functions by regulating Ca(2+) stores, antibody secretion and integrin activation.

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.

Ku antigen consists of two polypeptides (70 kDa and 80 kDa; the p80 subunit is occasionally called p86). The Ku heterodimer provides DNA-binding and regulatory functions to DNA-dependent protein kinase which is a central enzyme for DNA recombination processes in eucaryotic cells. The Ku protein plays important roles in multiple nuclear processes including DNA repair, V(D)J recombination, telomere maintenance, and the regulation of specific gene transcription.
Antibodies to Ku were originally reported in scleroderma-polymyositis overlap syndrome (up to 20% of patients) but have also been detectable in about 20 % of patients with primary pulmonary hypertension (as a complication of overlap), in 5-10 % of SLE and MCTD patients, and in up to 20 % of patients with primary Sj?gren's syndrome.
In IIF using HEp-2 cells, Ku-positive sera yield a dense, fine granular pattern with nucleolar staining that is typical but not specific for anti-Ku. Detection of Ku antibodies by Western blot may bear false-negative results since the main reactive epitope on the p70/p80 heterodimer is conformation-dependent.

Mammalian mitochondrial ribosomal proteins are encoded by nuclear genes and assist in protein synthesis within the mitochondrion. Mitochondrial ribosomes (mitoribosomes) consist of a small 28S subunit and a large 39S subunit (MRPL13 is a 39S subunit protein) and have an estimated 75% protein to rRNA composition compared to prokaryotic ribosomes, where this ratio is reversed. An additional difference between mammalian mitoribosomes and prokaryotic ribosomes is that the second contain a 5S rRNA. Among various species, the proteins comprising the mitoribosome differ greatly in sequence, and sometimes in biochemical properties, which prevents easy recognition by sequence homology.

Chemokine (C-X-C motif) ligand 5 (CXCL5) is a small cytokine belonging to the CXC chemokine family that is also known as epithelial-derived neutrophil-activating peptide 78 (ENA-78). It is produced following stimulation of cells with the inflammatory cytokines interleukin-1 or tumor necrosis factor-alpha. Expression of CXCL5 has also been observed in eosinophils, and can be inhibited with the type II interferon IFN-?. This chemokine stimulates the chemotaxis of neutrophils possesses angiogenic properties. It elicits these effects by interacting with the cell surface chemokine receptor CXCR2. The gene for CXCL5 is encoded on four exons and is located on human chromosome 4 amongst several other CXC chemokine genes. CXCL5 has been implicated in connective tissue remodelling.