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Methionine sulfoxide reductase B1 (SEPX1 or MSRB1), is a selenoprotein that contains a selenocysteine (Sec) residue at its active site. The selenocysteine is encoded by the UGA codon that usually signals translation termination. SEPX1 is a member of the methionine sulfoxide reductase B (MsrB) family, and is expressed in an assortment of adult and fetal tissues. MSRs (Methionine sulfoxide reductases) catalyze the reduction of free and protein-bound methionine sulfoxides to corresponding methionines. The oxidation of methionine by ROS creates a diastereomeric mixture of methionine-S-sulfoxide (Met-S-SO) and methionine-R-sulfoxide (Met-R-SO). Two separate enzyme families evolved for reduction of these sulfoxides, with methionine-S-sulfoxide reductase (MsrA) being stereospecific for Met-S-SO and methionine-R-sulfoxide reductase (MsrB) for Met-R-SO.

NAPA is part of the SNAP (Soluble NSF Attachment Protein) family. SNAPs, acting together with SNAREs (SNAP receptors) and the N-ethylmaleimide-sensitive fusion protein (NSF), are necessary for the fusion of transport vesicles to their objective membranes in synaptic transmission, intra-Golgi transport, endosome-to-endosome fusion and transcytotic vesicles-to-plasma membrane transport. NAPA is in charge of the binding of NSF and therefore the formation of a 20S fusion particle.

S100A8 is a part of the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100 proteins are localized in the cytoplasm and/or nucleus of a broad range of cells, and participate in the regulation of cellular processes such as cell cycle progression and differentiation. S100A8 plays a role in the inhibition of casein kinase and as a cytokine. S100A8 altered expression is related with cystic fibrosis disease. S100A8 is a calcium-binding protein that has antimicrobial activity against bacteria and fungi.S100A8 is crucial for resistance towards invasion by pathogenic bacteria. S100A8 up-regulates transcription of genes that are under the control of NF-kappa-B. S100A8 plays a role in the development of endotoxic shock in response to bacterial lipopolysaccharide. S100A8 endorses tubulin polymerization and promotes phagocyte migration and infiltration of granulocytes at sites of wounding. S100A8 takes part as a pro-inflammatory mediator in acute and chronic inflammation and up-regulates the release of IL8 and cell-surface expression of ICAM1.

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, 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.

Omentin is a recently recognized gene highly localized to the mental tissue (visceral adipose tissue). Omentin is present in the stromal vascular cells in the adipose tissue rather than in the adipocytes. Omentin is predominantly expressed in the visceral adipose tissue than the subcutaneous tissue, with the omentin mRNA being 150 times higher in the visceral adipose tissue. Omentin has also been detected in human blood using western blot analysis, and seems to increase insulin-stimulated glucose uptake in 3T3-L1 adipocytes in mice. Omentin seems to increase Akt phosphorylation irrespective of insulin presence. Its role in glucose metabolism and obesity remains to be described; an insulin-sensitizing action is possible.Differences in Omentin expression has been noted in adipose tissue from normals and patients with inflammatory bowel disease although its significance is unknown.

Persephin is a member of the GDNF ligand subfamily of the TGF-beta superfamily. PSPN encourages the existence and growth of key dopaminergic and motor neurons, as well as taking part in kidney development. Nonetheless, persephin does not support existence of peripheral neurons.

Microseminoprotein is a member of the immunoglobulin binding factor family. It is synthesized by the epithelial cells of the prostate gland and secreted into the seminal plasma. This protein has inhibin-like activity. It may have a role as an autocrine paracrine factor in uterine, breast and other female reproductive tissues. The expression of the encoded protein is found to be decreased in prostate cancer. Two alternatively spliced transcript variants encoding different isoforms are described for this gene. The use of alternate polyadenylation sites has been found for this gene.

Beta-casein precursor (CSN2) is a member of the beta-casein family. CSN2 has an imperative role in determination of the surface properties of the casein micelles. CSN2 is specific to mammary glands and is secreted in milk.

NPM2 is a member of nucleoplasmin family. NPM2 is a core histones chaperone which takes part in chromatin reprogramming, particularly throughout fertilization and early embryonic development. NPM2 also takes part in sperm DNA decondensation during fertilization.

Single-Stranded DNA Binding Protein 1 (SSBP) participates in mitochondrial biogenesis. SSBP binds preferentially and cooperatively to ss-DNA. The SSBP protein is involved in mitochondrial DNA replication and associates with mitochondrial DNA.

Myelin Protein Zero-Like 1 (MPZL1) is a cell surface receptor, which is involved in signal transduction processes. MPZL1 recruits PTPN11/SHP-2 to the cell membrane and is a putative substrate of PTPN11/SHP-2. MPZL1 is a main receptor for concanavalin-A (ConA) and it is involved in cellular signaling induced by ConA, which most likely includes Src family tyrosine-protein kinases. MPZL1 Isoform 3 appears to have a dominant negative role by blocking tyrosine phosphorylation of MPZL1 induced by ConA. Isoform 1, but not isoform 2 and isoform 3, might be involved in regulation of integrin-mediated cell motility.

IFT20 is a fragment of intraflagellar transport (IFT) elements which takes part in ciliary process assembly. IFT20 is involved in the transferring of ciliary membrane proteins from the Golgi complex to the cilium and is expressed in virtually all tissues.

Cadherin-5 (CDH5) belongs to the atypical/type 2 subgroup of Cadherin homophilic adhesion proteins. Cadherin-5 is a calcium-dependent cell-cell adhesion molecule, which is comprised of 5 extracellular cadherin repeats, a transmembrane region and a highly conserved cytoplasmic tail. Cadherin-5 protein plays a role in the formation, maturation and remodeling of the vascular wall. CDH5 is generally considered to be specific for vascular endothelia in which it is either the sole or the predominant cadherin, often co-existing with N-cadherin. Moreover, the CDH5 protein regulates or is regulated by VEGF R2, type 1 and type 2 TGF-beta receptors, and other endothelial junction proteins such as JAM-C, Claudin-5, and N-Cadherin. CDH5 also connects with alpha-catenin forming a link to the cytoskeleton. CDH5 functions jointly with KRIT1 to create and maintain correct endothelial cell polarity and vascular lumen. Furthermore, Cadherin-5 is essential for activation of PRKCZ and for the localization of phosphorylated PRKCZ, PARD3, TIAM1 and RAP1B to the cell junction. The CDH5 gene is located in a gene cluster in a region on the long arm of chromosome 16 which is involved in loss of heterozygosity events in breast and prostate cancer.

C-type lectin domain family 7 member A 1 or CLEC7A is a protein, that in the innate immune system, acts against fungal pathogens. CLEC7A can be found in the immune system response cells such as monocytes, macrophages & neutrophils, or in dendritic and T cells. The protein is enhanced by macrophages by using GM-CSF, IL-4, or IL-13, or diminishes by dexamethasone, IL-10 and LPS.

Microtubule-associated protein tau (MAPT or Tau) is a protein that stabilizes microtubules. MAPT is abundant in neurons in the central nervous system and is less common elsewhere. When MAPT is defective, and no longer stabilizes microtubules properly, it can result in dementias, such as Alzheimer's disease.

Filamin binding LIM protein 1 (FBLIM1) plays a role as an anchoring site for cell-ECM adhesion proteins and filamin-containing actin filaments. FBLIM1 is involved in cell shape spreading and motility. FBLIM1 participates in the regulation of filamin-mediated cross-linking and stabilization of actin filaments. FBLIM1 promotes stimulation of integrins and regulates integrin-mediated cell-cell adhesion.

Junctional Adhesion Molecule 2 (JAM2) is a member of the immunoglobulin superfamily, and the junctional adhesion molecule (JAM) family. JAM2 is a type I membrane protein which is localized at the tight junctions of both epithelial and endothelial cells. JAM2 functions as an adhesive ligand for interacting with various immune cell types, and may have a role in lymphocyte homing to secondary lymphoid organs.

RWD domain-containing protein 4 is also known as RWDD4.

SNCA or Alpha-synuclein is a protein with undisclosed function that mainly concentrated in the brain tissue, mainly in the tips of the neurons in the presynaptic terminals. Almost 1% of the proteins in the brain tissues are synucleins. The protein is located mainly in the hippocampus, thalamus, cerebellum & neocortex. Smaller amounts of the SNCA protein can be found in the neuroglial cells. The MITF protein regulates the SNCA expression in melanocytic cells.

ArsA Arsenite Transporter, ATP-Binding, Homolog 1 (ASNA1) is a part of the arsA ATPase family. ASNA1 is the human homolog of the bacterial arsA gene. ArsA ATPase is the catalytic component of a multisubunit oxyanion pump In E.coli, which is in charge for resistance to arsenicals and antimonials. ASNA1 is also a main component of a transmembrane domain (TMD) recognition complex (TRC) which is involved in the post-translational delivery of tail-anchored (TA) proteins from the cytosol to the endoplasmic reticulum (ER).

SOD2 is part of the iron/manganese superoxide dismutase family. It encodes a mitochondrial protein that forms a homotetramer and binds one manganese ion per subunit. SOD2 binds to the superoxide byproducts of oxidative phosphorylation and converts them to hydrogen peroxide and diatomic oxygen. Mutations in SOD2 gene have been associated with idiopathic cardiomyopathy (IDC), premature aging, sporadic motor neuron disease, and cancer. SOD2 destroys radicals which are usually produced within the cells and which are toxic to biological systems.

Galectin-4 is a member of the subfamily of galectins composed of two carbohydrate recognition domains having similar peptide chains. The galectins are a family of beta-galactoside-binding proteins having a role in modulating cell-cell and cell-matrix interactions, which inhibits chronic inflammations, GVHD, and allergic responses. LGALS4 expression is limited to small intestine, colon, and rectum, and it is underexpressed in colorectal cancer. LGALS4 binds as an endogenous ligand to glycosphingolipids having 3-O-sulfated Gal residues and bind as well to cholesterol-3-sulfate. LGALS4 takes part in cell adhesion. LGALS4 plays a role in crosslinking the lateral cell membranes of the surface-lining epithelial cells, thus supporting epithelial integrity against mechanical stress exerted by the bowel lume. LGALS4 is in charge of intestinal inflammation via selective regulation of peripheral and mucosal T-cell cell cycle, in addition to cell death by apoptosis of T-cells by a pathway independent of the activation of caspases. LGALS4 blockade decreases TNF-alpha inhibitor induced T-cell death. LGALS4 decreases pro-inflammatory cytokine secretion including IL-6 & IL-17.

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.

MYL9 is one of the numerous regulatory myosin light chains. Myosin which is a structural component of the muscle consists of 2 heavy chains and 4 light chains. MYL9 is a myosin light chain regulates muscle contraction by modulating the ATPase activity of myosin heads. MYL9 binds calcium and is activated by myosin light chain kinase. Regulatory myosin light chains regulate contraction in smooth muscle and non-muscle cells via phosphorylation by MLCK (myosin light chain kinase). Phosphorylation of regulatory myosin light chains is catalyzed by MLCK in the presence of calcium and calmodulin and it increases the actin-activated myosin ATPase activity, thus regulates the contractile activity.