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MAPKSP1 is a scaffold protein which operates in the extracellular signal-regulated kinase (ERK) cascade. MAPKSP1 protein is restricted to late endosomes by the mitogen-activated protein-binding protein-interacting protein, and binds specifically to MAP kinase kinase MAP2K1/MEK1, MAP kinase MAPK3/ERK1, and MAP kinase MAPK1/ERK2.

CDC34 is important in the control of cell cycle and DNA replication. Cdc34 in association with different E3 complexes, including SCF, has been shown to target many different substrates for ubiquitination and degradation during cell division, signal transduction, and development. Cdc34 substrates that have been characterized include I?B, B-Myb, Wee1, MyoD, ICERII?, ATF5, p27Xic1, and p27Kip1. Additionally, substrates such as ?-catenin, p21Cip1, E2F, cyclin E, and cyclin D are putative substrates of Cdc34 by virtue of their SCF requirement for proteolysis. Cdc34 has been demonstrated to self-associate through a domain in the C-terminus, and is phosphorylated and ubiquitinylated in vivo. This protein is useful for in vitro ubiquitinylation reactions.

SDF-1 (stromal cell-derived factor-1) is small cytokine belonging to the chemokine family that is officially designated Chemokine (C-X-C motif) ligand 12 (CXCL12). It is produced in two forms, SDF-1?/CXCL12a and SDF-1?/CXCL12b, by alternate splicing of the same gene. Chemokines are characterized by the presence of four conserved cysteines, which form two disulfide bonds. The CXCL12 proteins belong to the group of CXC chemokines, whose initial pair of cysteines are separated by one intervening amino acid. CXCL12 is strongly chemotactic for lymphocytes and has been implicated as an important cell co-ordinator during development. During embryogenesis it directs the migration of hematopoietic cells from foetal liver to bone marrow. Mice which were knocked-out for CXCL12 gene were lethal before the birth or within just 1 hour of life. As another role, CXCL12a alters also the electrophysiology of neurons. CXCL12 was shown to be expressend in many tissues in mice (including brain, thymus, heart, lung, liver, kidney, spleen and bone marrow).
The receptor for this chemokine is CXCR4, which was previously called fusin. This CXCL12-CXCR4 interaction used to be considered exclusive (unlike for other chemokines and their receptors), but recently it was suggested that CXCL12 is also bound by CXCR7 receptor.
The gene for CXCL12 is located on human chromosome 10. In human and mouse both CXCL12 and CXCR4 show high identity of sequence: 99% and 90%, respectively.

YOD1 is a Hydrolase which removes conjugated ubiquitin from proteins and takes part in endoplasmic reticulum-associated degradation (ERAD) for misfolded lumenal proteins. YOD1 is a highly conserved deubiquitinating enzyme belonging to the ovarian tumor (otubain) family, whose function has yet to be determined in mammalian cells. YOD1 is a component of a multiprotein complex with p97 as its nucleus, proposing a functional link to a pathway responsible for the dislocation of misfolded proteins from the endoplasmic reticulum. YOD1 variant xpression deprived of its deubiquitinating activity compels a halt on the dislocation reaction, as concluded by the stabilization of various dislocation substrates.

Thioredoxins are small disulphide-containing redox proteins (within the conserved Cys-Gly-Pro-Cys active site) that have been found in all the kingdoms of living organisms. Thioredoxin contains a single disulfide active site and serves as a general protein disulphide oxidoreductase. Thioredoxins are involved in the first unique step in DNA synthesis. It interacts with a broad range of proteins by a redox mechanism based on reversible oxidation of two cysteine thiol groups to a disulphide, accompanied by the transfer of two electrons and two protons. The net result is the covalent interconversion of a disulphide and a dithiol. Trx also provides control over a number of transcription factors affecting cell proliferation and death through a mechanism referred to as redox regulation. It has been suggested that thioredoxin may catalyze the formation of correct disulfides during protein folding because of its ability to act as an efficient oxidoreductant. This could be especially useful in refolding proteins expressed in E. coli. To this end, thioredoxin has been shown to act as a protein disulfide isomerase.Its Molecular Weight is 11.9kDa. and the pI is 4.67.

Lysyl Oxidase also known as LOX is an extracellular copper enzyme which initiates the crosslinking of collagens and elastin. LOX catalyzes oxidative deamination of the epsilon-amino group in certain lysine and hydroxylysine residues of collagens and lysine residues of elastin. Adding up to crosslinking extracellular matrix proteins, LOX plays a part in tumor suppression. Moreover, defects in LOX are the cause of autosomal recessive cutis laxa type I, CL type I. Two transcript variants encoding dissimilar isoforms have been found for LOX.

Leukemia inhibitory factor, is a pleiotropic cytokine which is expressed by numerous cells including activated T lymphocytes, monocytes, mast cells and neuronal cells. LIF takes part in the induction of hematopoietic differentiation in normal and myeloid leukemia cells, induction of neuronal cell differentiation, regulator of mesenchymal to epithelial conversion during kidney development, and is a key player in immune tolerance at the maternal-fetal interface.

The 14-3-3 family of proteins plays a key regulatory role in signal transduction, checkpoint control, apoptotic and nutrient-sensing pathways. 14-3-3 proteins are highly conserved and ubiquitously expressed. There are at least seven isoforms, β, γ, ε, σ, ζ, τ and η that have been identified in mammals. The 14-3-3 tau, a subtype of the 14-3-3 family of proteins, was found in T Cells, brain and testes. This 14-3-3 tau is upregulated in patients with amyotrophic lateral sclerosis.

Terlipressin is similar to a naturally occurring hormone present in the body, known as antidiuretic hormone (ADH) or vasopressin. ADH has two main effects in the body. Firstly, it causes narrowing of blood vessels (vasoconstriction), thereby limiting blood flow to a particular area of the body. It also acts on receptors in the kidney to retain water in the body, which helps to prevent excessive loss of water in the urine. Terlipressin is commonly used to stop bleeding of varices in the food pipe (oesophagus). Varices are fragile distended veins that can occur in various parts of the body such as the oesophagus. This is caused by an increase in blood pressure in certain diseases such as severe liver disease. These fragile varices can rupture and lead to life threatening bleeding. Terlipressin is therefore given to narrow blood vessels, and so restricting blood flow to the varices and stopping the bleeding.

Hemopexin (or haemopexin) is a plasma protein that binds heme with the highest affinity of any known protein. Hemopexin is generally expressed in liver, and belongs to acute phase reactants, the synthesis of which is induced after inflammation. Heme is potentially very toxic because of its ability to intercalate into lipid membrane and to generate hydroxyl radicals. Hemopexin’s function of scavenging the heme released or lost by the turnover of heme proteins such as hemoglobin defends the body from the oxidative damage that free heme can cause. Additionally, hemopexin discharges its bound ligand for internalisation upon interacting with a specific receptor located on the surface of liver cells. This hemopexin function is in order to preserve the body's iron. Hemopexin’s levels in the serum are an indication of how much heme is present in the blood. Low Hemopexin levels show that there is a lot of it in the serum. For that reason, low hemopexin levels indicate that there has been consid

HEXA is the alpha subunit of the lysosomal enzyme beta-hexosaminidase which, combined with the cofactor GM2 activator protein, catalyzes the degradation of the ganglioside GM2, and other molecules having N-acetyl hexosamines terminus. The two subunits composing Beta-hexosaminidase, alpha and beta, belong to the glycosyl hydrolases family and are encoded by distinct genes. Alpha subunit gene mutations can cause Tay-Sachs disease (GM2-gangliosidosis type I).

MX2 is a member of 2 protein families: the dynamin family and the large GTPases family. MX2 has a cytoplasmic and nuclear structure which is found in a granular pattern in the heterochromatin region under the nuclear envelope. The nuclear form has a NLS (nuclear localization signal) at the amino terminal end however it is missing in the cytoplasmic form as a result of the use of a different translation start codon. MX2 is upregulated by IFN-a, but unlike myxovirus resistance protein 1 has no antiviral activity.

ZMAT3 is a protein with a nuclear localization signal and 3 zinc finger domains. The mRNA and the protein of this gene are upregulated by wildtype p53. When overexpressed, ZMAT3 can produce tumor cell growth, indicating that ZMAT3 takes part in the p53-dependent growth regulatory pathway. Alternative splicing of ZMAT3 produce two transcript variants encoding two isoforms differing in only one amino acid.

Anthrax toxin receptor 2, also known as ANTXR2, takes part in the configuration of little blood vessels (capillaries). ANTXR2 helps the toxin that leads to anthrax to attach to cells and trigger illness. ANTXR2 is necessary for cellular interactions with laminin and the extracellular matrix.

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.

Thioredoxin reductase (TrxR/NTR), an enzyme belonging to the flavoprotein family of pyridine nucleotide-disulfide oxidoreductases. Thioredoxin reductase (TrxR), a component of the thioredoxin system, including thioredoxin (Trx) and NADPH, catalyzes the transfer of electrons from NADPH to Trx, acts as a reductant of disulfide-containing proteins and participates in the defense system against oxidative stresses.

WARS is part of the class I tRNA synthetase family. 2 types of tryptophanyl tRNA synthetase exist, a cytoplasmic form, called WARS, and a mitochondrial form, called WARS2. WARS catalyzes the aminoacylation of tRNA(trp) with tryptophan and is induced by INF. WARS controls ERK, Akt, and eNOS activation pathways that are related with angiogenesis, cytoskeletal reorganization and shear stress-responsive gene expression.

XCL1 is a small cytokine belongs to the XC chemokine family that is also known as lymphotactin. XCL1 is found in high levels in spleen, thymus, intestine and peripheral blood leukocytes, and at lower levels in lung, prostate gland and ovary. Cellular sources for XCL1 include activated thymic and peripheral blood CD8+ T cells. This chemokine attracts T cells. In humans, XCL1 is closely related to XCL2, whose gene is found at the same locus on chromosome 1. XCL1 induces it chemotactic function by binding to a chemokine receptor called XCR1.

BSND is a vital beta subunit for CLC chloride channels. These heteromeric channels are restricted to basolateral membranes of renal tubules and of potassium-secreting epithelia of the inner ear. BSND gene mutations are linked with Bartter syndrome with sensorineural deafness.

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.

Listeriolysin O (aka LLO) is a hemolysin produced by Listeria monocytogenes bacteria, the pathogen responsible for causing listeriosis. The toxin may be regarded as a virulence factor, since it is crucial for the virulence of L. monocytogenes. LLO is a single polypeptide protein encoded by the hlyA gene and composed of 529 residues. LLO is a thiol-activated cholesterol-dependent pore forming toxin protein; therefore, it is activated by reducing agents and inhibited by oxidizing agents. Still, LLO differs from other thiol-activated toxins, as its cytolytic activity is maximized at a pH of 5.5. Inside the acidic phagosomes (average pH ~ 5.9) of cells that have phagocytosed L. monocytogenes, LLO is selectively activated by maximizing activity at a pH of 5.5. Following the phagosome lysis by LLO, the bacterium breaks out into the cytosol, where it is able to grow intracellularly, and the toxin has reduced activity in the more basic cytosol. Thus, LLO permits L. monocytogenes to break out from the phagosomes into the cytosol without harming the plasma membrane of the infected cell, which allows the bacteria to live intracellularly, where they are sheltered from extracellular immune system factors such as the complement system and antibodies. LLO also brings about dephosphorylation of histone H3 and deacetylation of histone H4 in the early phases of infection, before entry of L. monocytogenes into the host cell. The pore-forming activity is not implicated in causing the histone modifications. The modifications of the histones affect the down regulation of genes encoding proteins involved in the inflammatory response. Therefore, LLO may be significant in subverting the host immune response to L. monocytogenes. At its NH2-terminus it possesses a 25 residues long typical signal sequence excited during the secretion process. Moreover, in its NH2-terminus there is also a 19 amino acids PEST- like sequence that may target this toxin for degradation. The PEST-like sequence found in LLO and is considered crucial for virulence, given that mutants lacking the sequence lysed the host cell. Nevertheless, contrary to PEST's supposed role in protein degradation, evidence implies that the PEST-like sequence may control LLO production in the cytosol rather than increase degradation of LLO.

Cathepsin D is synthesized as a 54kDa precursor, which is proteolytically processed to an intermediate 48kDa single chain, which matures into more stable 34kDa and 14kDa two chain form. It is an estrogen-regulated lysosomal protease that has been suggested to facilitate cancer cell migration and invasion by digesting the basement membrane, extracellular matrix, and xonnective tissue. Because of its mitogenic and proteolytic activities, it has been implicated as a prognostic marker in many tumor types. Cathepsin D is expressed in epithelial cells as well as in macrophages.

SEMA3C, also known as Semaphorin 3C, is a member of the semaphorin family 3 that are grouped into 8 major classes based on phylogenetic tree analyses and structure. Class 3 have an important function after traumatic central nervous system injuries. SEMA3C regulates neuronal and non-neuronal cells associated with the traumatic injury due to their presence in the scar tissue. SEMA3C is expressed in all somatic motor neurons, in cardiac neural crest cells during development and in lung buds. The SEMA3C functions are mediated through binding to the Plexin-D1 and Neuropilin 1 or Neuropilin 2 coreceptor complex. SEMA3C activates integrins in certain cells, so besides its repulsive activities, it also acts as a chemoattractant.

ANXA4 is part of the annexin family of calcium-dependent phospholipid binding proteins. ANXA4 has 45%-59% identity with other proteins of its family and shares a related size and exon-intron organization. ANXA4 interacts with ATP, and has in vitro anticoagulant activity and also inhibits phospholipase A2 activity. ANXA4 is exclusively expressed in epithelial cells. ANXA4 is a Calcium/phospholipid-binding protein which promotes membrane fusion and is involved in exocytosis.