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Frataxin is a mitochondrial iron binding protein that is part of the FRATAXIN family. Frataxin functions in regulating mitochondrial iron transport and respiration. The expansion of intronic trinucleotide repeat GAA results in Friedreich ataxia. Frataxin plays a role in iron homeostasis. Frataxin is an anti-apoptotic protein which prevents mitochondrial damage and reactive oxygen species (ROS) production.

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

Integrin Beta 3 Binding Protein (ITGB3BP1) is a broadly expressed protein which contains a DD1 or RepD1 domain and an LXXLL motif. ITGB3BP1 functions as a nuclear receptor coactivator while induced by estrogen. ITGB3BP1 is also relates with the CENP-A-CAD complex that is engaged in mitotic progression, the assembly of kinetochore proteins and chromosome segregation. ITGB3BP1 behave s as a transcriptional corepressor via its interaction with the NFKB1 NF-kappa-B subunit by interfering with the transactivation domain of NFKB1.

Complement Factor Properdin (CFP) which is a plasma glycoprotein, is a positive regulator of the alternative complement pathway of the innate immune system. CFP binds and stabilizes the C3- and C5-convertase enzyme complexes in a feedback loop that eventually ends with formation of the membrane attack complex and lysis of the target cell. Mutations in CFP lead to 2 forms of properdin deficiency that cause high susceptibility to meningococcal infections.

EFNB1 is a member of the Eph family. The cell-surface proteins Ephrins split into two groups, ephrin-A and ephrin-B, based on their structure and function and perform as ligands for Eph receptors. The transmembrane EFNB1 proteins have conserved cytoplasmic tyrosine residues that are phosphorylated upon interaction with an EphB receptor. In addition, EFNB1 transduces outside-in signals by C-terminal protein interfaces which influence integrin-mediated cell attachment and migration.

SRP54 is a 54-kDa subunit of the signal recognition particle (SRP), a cytoplasmic ribonucleoprotein complex which leads the translocation of newly synthesized secretory proteins from the polysome to the endoplasmic reticulum. SRP is composed of six polypeptides and a tRNA-like molecule known as 7SL RNA. SRP54 is a GTP-binding protein that directly binds the signal sequences of nascent secretory and membrane proteins. Anti-SRP autoantibodies take place in patients with an autoimmune chronic muscle inflammation called polymyositis. These auto-antibodies predominantly recognize the SRP54 subunit and in addition are able to immunoprecipitate several of the SRP subunits and the RNA component. Nearly 5% of myositis patients are positive for anti-SRP autoantibodies, increasing to 18% in the subgroup of Jo-1 autoantibody-negative patients. The classic 'anti-SRP syndrome' is a severe form of polymyositis in which the myositic inflammation is acute and aggressive onset, with common myalgias and cardiac involvement. Normally there is a poor reaction to therapy with a 5-year survival rate of about 25%.

STMN3 is a neuronal specific protein which belongs to the stathmin/oncoprotein 18 family of microtubule-destabilizing phosphoproteins. It is similar to the SCG10 protein and is involved in signal transduction and regulation of microtubule dynamics.

Endoplasmic reticulum protein 27kDa (ERP27) is a widely expressed protein which localizes to the ER and may act as a protease, protein disulfide isomerase, thiol-disulfide oxidase or phospholipase. ERP27 doesn’t contain a CXXC active site motif indicating that it is a catalytically redox-inactive member of the protein disulfide isomerase family.

Growth Hormone Binding Protein or GHR, is a protein, part of the cytokine receptor superfamily. GHR binds to 2 receptors, therefore it enhances signal transduction via dimerization of receptors. In elevated levels, growth hormone operates as an antagonist due to high variance in the binding sites affinities. The antagonist operation can be embellished even more when the binding site is reduced its affinity.

Lumican also known as LUM belongs to the small leucine-rich proteoglycan (SLRP) family which comprises decorin, biglycan, fibromodulin, keratocan, epiphycan, and osteoglycin. Furthermore we can see that in these bifunctional molecules, the protein moiety binds collagen fibrils and the highly charged hydrophilic glycosaminoglycans regulate interfibrillar spacings. Lumican is the main keratan sulfate proteoglycan of the cornea however LUM is also distributed in interstitial collagenous matrices throughout the body. Lumican regulates collagen fibril organization and circumferential growth, corneal transparency, epithelial cell migration and tissue repair. Among the diseases associated with LUM is posterior amorphous corneal dystrophy.

C-Type Lectin Domain Family 10, Member A (CLEC10A) is a part of the C-type lectin superfamily. CLEC10A is expressed in immature myeloid dendritic cells and alternatively activated macrophages. CLEC10A takes part in regulating adaptive and innate immune responses and also binds in a calcium dependent way to terminal galactose and N-acetylgalactosamine, linked to serine or threonine.

GRPEL1 is a vital component of the PAM complex, a complex necessary for the translocation of transit peptide-containing proteins from the inner membrane into the mitochondrial matrix in an ATP-dependent manner. GRPEL1 protein controls the nucleotide-dependent binding of mitochondrial HSP70 to substrate proteins.

Clusterin also known as 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 5 disulfide bridges and are flanked by 2 predicted coiled-coil a-helices and 3 predicted amphipathic a-helices.
Across a broad range of species clusterin shows a high degree of sequence homology ranging from 70% -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.
Clusterin is up/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 Rab-35 (RAB35) is restricted to the plasma membrane and endocytic compartments and controls a fast endocytic recycling pathway. Inhibition of Rab35 function leads to the accumulation of endocytic markers on numerous cytoplasmic vacuoles in cells that failed cytokinesis, which is consistent with a central requirement for Rab35-regulated recycling during cell division.

Ribosomes are the organelles which catalyze protein synthesis and comprised of a small 40S subunit and a large 60S subunit. Combined, the small 40S and large 60S subunits are composed of 4 RNA types and about 80 structurally distinct proteins. RPS16, a ribosomal protein, is a component of the 40S subunit and a member of the S9P family of ribosomal proteins. RPS16 is situated in the cytoplasm. Just like other genes encoding ribosomal proteins, there are numerous processed pseudogenes of RPS16 spread through the genome.

Receptor Transporter Protein 4 (RTP4) is a member of the TMEM7 family.

S100A4 is part of the S100 super-family of proteins containing 2 EF-hand calcium binding domains. S100A4 is ubiquitously overexpressed and is localized in the cytoplasm and/or nucleus. S100A4 is involved in motility, invasion, and tubulin polymerization. Chromosomal rearrangements and altered expression of the S100A4 gene have been implicated in tumor metastasis.

Cathepsin-E also known as CTSE is a gastric aspartyl protease which functions as a disulfide-linked homodimer. CTSE belongs to the peptidase C1 family; furthermore it has specificity similar to pepsin A and cathepsin D. CTSE is an intracellular proteinase which does not seem to be involved in the digestion of dietary protein and is found in the uppermost concentration in the surface of epithelial mucus-producing cells of the stomach. CTSE is the first aspartic proteinaseexpressed in the fetal stomach and is discovered in more than half of gastric cancers. For that reason CTSE is anoncofetal antigen. In addition, transcript variants utilizing alternative polyadenylation signals and two transcript variantsencoding different isoforms exist for this gene.

AKT Serine/Threonine Kinase 3 (Akt3) is a member of the Akt subfamily of serine/threonine protein kinases. Akt3is 1/3 closely related serine/threonine-protein kinases (Akt1, Akt2 and Akt3) called the Akt kinase and which regulate various processes including proliferation, metabolism, cell survival, growth and angiogenesis. The mentioned above is mediated through serine and/or threonine phosphorylation of a range of downstream substrates. Akt3 takes part in brain development and is critical for the viability of malignant glioma cells.

Annexin VII is a member of the annexin family of calcium-dependent phospholipid binding proteins. Annexin VII has molecular weight of approximately 51 kDa with a unique, highly hydrophobic N-terminal domain of 167 amino acids and a conserved C-terminal region of 299 amino acids. The latter domain is composed of alternating hydrophobic and hydrophilic segments. Structural analysis of the protein suggests that Annexin VII is a membrane binding protein with diverse properties including voltage-sensitive calcium channel activity, ion selectivity and membrane fusion.

Ephrin-B3 (EFNB3) which belongs to the ephrin gene family is essential in brain development as well as in its maintenance. EFNB3 binds to, and induces the collapse of, commissural axons/growth cones in vitro. EFNB3 loosely binds Eph receptors located on bordering cells, leading to contact-dependent bidirectional signaling into neighboring cells. The EPH and EPH-related receptors comprise the largest subfamily of receptor protein-tyrosine kinases and are implicated in mediating developmental events, mostly in the nervous 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.

FAS / CD95 is a 36kDa transmembrane type I receptor, which belongs to the NF/NGF receptor super-family. It is a potent inducer of apoptosis in cells of the immune system upon interaction with its natural ligand, CD95L. Although the CD95/CD95L system could play a role in tumor regression, tumor cells seem to down-regulate CD95 expression as a mechanism of resistance to CD95L-induced killing by T lymphocytes and NK cells. The Fas antigen is expressed on the surface of various cell types, including activated T and B lymphocytes and T lymphoblastoid cell line. CD95 is also expressed in a broad panel of non-transformed cells outside the immune system.