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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 epsilon, a subtype of the 14-3-3 family of proteins, was thought to be brain and neuron-specific. It has been shown to interact with CDC25 phosphatases, RAF1 and IRS1 proteins, suggesting its role in diverse biochemical activities related to signal transduction, such as cell division and regulation of sensitivity. It has also been implicated in the pathogenesis of small cell lung cancer.

Tyrosine 3-monooxygenase (Th), is a rate-limiting enzyme in catecholamine synthesis. Th utilizes tetrahydrobiopterin as well as molecular oxygen to convert tyrosine to DOPA. Th regulates dopamine (DA) neurotransmission at the biosynthesis and reuptake steps. Th takes a vital part in the physiology of adrenergic neurons. Furthermore, Th effects overexpression in lymphocytes on the differentiation as well as function of T helper cells.

Beta-galactosidase or GLB1 is a B-galactosidase found in the lysosome. This enzyme hydrolyzes the finale B-galactose from the precursors ganglioside & keratin sulfate. GLB1 has a crucial part in the creation of elastogenesis (extracellular elastic fibers) and connective tissue development. This enzyme is similar to elastin-binding protein which is a key part in non-integrin cell surface receptor. In cells that extort elastin GLB1 is linked to tropoelastin intracellularly and act as recycling molecular chaperone.

Recombinant Hirudin is a potent thrombin inhibitor originally derived from the medicinal leech. Hirudin acts directly on thrombin rather than through other clotting factors. The mechanism of Hirudin-thrombin appears to be unique. The conversion of fibrinogen into fibrin by the serine protease enzyme thrombin is a major event in the final stages of blood coagulation. In the final stages of coagulation prothrombinase converts prothrombin into thrombin. Fibrin is subsequently cross linked by factor XIII to form a blood clot. The primary inhibitor of thrombin in normal blood circulation is antithrombin III. The anticoagulatant activity of hirudin is derived from its ability to inhibit the pro-coagulant activity of thrombin (similar to antithrombin III activity). Hirudin is the strongest natural inhibitor of thrombin. Hirudin binds to and inhibits only the activity of thrombin forms with a specific activity on fibrinogen contrasting to antithrombin III activity. Therefore, hirudin has a thrombolytic activity since it prevents or dissolves the formation of clots and thrombi. Hirudin also has therapeutic significance in blood coagulation disorders, in the treatment of skin hematomas and of superficial varicose veins. Hirudin does not hinder with the biological activity of other serum proteins and can also act on complexed thrombin, thus having an advantage over more common anticoagulants and thrombolytics. It is complicated to extract large quantities of hirudin from natural sources; therefore a method for producing and purifying hirudin using recombinant biotechnology has been developed.

Gastric Inhibitory Polypeptide (GIP) which is a significant hormone of the enteroinsular axis has a functional profile of possible therapeutic value for type 2 diabetes. GIP is an important incretin hormone released into the circulation from endocrine K-cells of the duodenum and jejunum after ingestion of food1. GIP was evaluated for his ability to elevate cellular cAMP production. GIP promotes plasma triglyceride clearance in response to oral fat loading.

The Trefoil Factor peptides (TFF1, TFF2 and TFF3) are stable secretory proteins expressed in the gastrointestinal tract (gastric mucosa), and are involved in intestinal mucosal defense and repair. TFF1 is an essential protein for normal differentiation of the antral and pyloric gastric mucosa and functions as a gastric-specific tumor suppressor gene. TFF1 is a stabilizer of the mucous gel overlying the gastrointestinal mucosa that provides a physical barrier against various noxious agents. TFF1 protects the mucosa from isults, stabilizes the mucus layer, & affects healing of the epithelium. TFF1 is commonly expressed in tumors. TFF1 is related with the cell membrane of MCF-7 cells. High levels of TFF1 and TFF2 are found in serum from inflammatory bowel disease.

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.

GSTK1 is involved in cellular detoxification. GSTK1 is localized to the peroxisome and catalyzes the conjugation of the thiol group of glutathione (GSH) to the electrophilic groups of a broad range of hydrophobic substrates, leading to an easier removal of the latter from the cells.

GSTP1 is a polymorphic gene encoding active, functionally different GSTP1 variant proteins that are believed to function in xenobiotic metabolism and have a part in susceptibility to cancer, and other diseases. GSTP1 is a glutathione S-transferase belonging to the pi class. GST family enzymes play a significant role in detoxification by catalyzing the conjugation of many hydrophobic and electrophilic compounds with reduced glutathione. Based upon the biochemical, immunologic and structural properties of the soluble GSTs they are grouped into 4 main classes: alpha, mu, pi, and theta. The GSTP1 enzyme acts by catalyzing the reaction of glutathione with an acceptor molecule to form a Sulfur-substituted glutathione. The reactions employing glutathione contribute the transformation of a broad range of electrophiles, including reactive products of lipid, protein, carcinogens, therapeutic drugs, environmental toxins, and products of oxidative stress.
The GSTP1 inactivation through CpG hypermethylation is frequent in pituitary adenomas and may be a factor in aggressive pituitary tumor behavior. GSTP1 is may be a transcriptional target of the p53 tumor suppressor gene. Single-nucleotide polymorphism in GSTP1 is linked to modified protein binding, which influence GSTP1's contribution to carcinogen and drug metabolism, and possibly disease pathogenesis and/or drug response. GST-pi might have central roles in proliferation of androgen-independent human prostate cancer cells.

X-Prolyl Aminopeptidase-1, also known as XPNPEP1 is a member of the peptidase M24B family. XPNPEP1 encodes the cytosolic form of a metalloaminopeptidase which catalyzes the cleavage of the N-terminal amino acid adjacent to a proline residue. Furthermore, XPNPEP1 plays a role in degradation as well as maturation of tachykinins, neuropeptides and peptide hormones.

MTHFS is a cytosolic protein which takes part in the formate metabolic process. MTHFS along with a magnesium cofactor catalyzes the ATP-dependent reaction which reduces 5-formyltetrahydrofolate (5-MTHF) to 5,10-methenyltetrahydrofolate(MTHF). MTHF is the substrate used by MTHFR (methylenetetrahydrofolate reductase) to generate 5-MTHF. In addition, MTHF is a coenzyme used in thymidine biosynthesis by thymidylate synthase (FAD).

Cysteine Conjugate-Beta Lyase Cytoplasmic also known as CCBL1 is a member of the class-I pyridoxal-phosphate-dependent aminotransferase family. CCBL1 catalyzes the irreversible transamination of the L-tryptophan metabolite L-kynurenine to form kynurenic acid (KA) it also metabolizes the cysteine conjugates of certain halogenated alkenes and alkanes to form reactive metabolites. Furthermore, CCBL1 catalyzes the beta-elimination of S-conjugates and Se-conjugates of L-(seleno) cysteine, resulting in the cleavage of the C-S or C-Se bond.

PRCP is a plasma protein which takes part in the cleavage of C-terminal amino acids linked to proline in proteinfor example angiotensin-2 & 3 at acidic pHenvironment rather than at neutral pHwhich exhibit less activity. This cleavage is important since Angiotensin-2 takes part in regulation of blood pressure & electrolyte balance which is essential to hypertension.

MMP-3 enzyme is also known as Stromelysin-1or as Transin-1 which hydrolyzes natural collagen at physiological pH and temperature. It dissolves the intervertebral nucleus pulposus and annulus fibrosus of Herniated Lumbar Intervertebral Disk . MMP-3 hydrolyzes components of the extracellular matrix like proteoglycan, laminin, fibronectin, gelatin and collagen types III, IV and IX. It also activates pro-MMP-9 and pro-MMP-8 and superactivates plasmin activated MMP-1. MMP-3 is secreted as a latent proenzyme and is activated by a variety of proteinases, e.g. plasmin, trypsin, chymotrypsin, cathepsin G or human neutrophil elastase. MMP-3 was found to be capable of activating the precursor of IL1-beta.

Matrix metalloproteinase-2 (MMP-2) is a type IV collagenase, which is involved in endometrial menstrual breakdown, regulation of vascularization and the inflammatory response. MMP-2 contains a number of distinct domains: a prodomain that is cleaved upon activation; a catalytic domain containing the zinc binding site; a fibronectin like domain believed to have a role in substrate targeting; and a carboxyl terminal (hemopexin like) domain containing 2 N-linked glycosylation. The MMP-2 can degrade an extensive array of substrates including type IV, V, VII and X collagens as well as gelatin type I. In addition, MMP-2 interacts with THBS2, TIMP2, Thrombospondin 1, CCL7 and TIMP4. MMP-2 autocatalytic cleavage in the C-terminal generates the anti-angiogenic peptide, PEX. This process seems to be made possible by binding integrinv/beta3. Defects in the MMP-2 are the cause of Torg-Winchester syndrome (TWS), aka multicentric osteolysis nodulosis and arthropathy (MONA).

Insulin-Degrading Enzyme (IDE) is a zinc metallopeptidase which degrades intracellular insulin, and thus terminates insulins activity, as well as playing a part in intercellular peptide signaling by degrading various peptides such as amylin, bradykinin, and kallidin. The preferential affinity of the IDE enzyme for insulin results in insulin-mediated inhibition of the degradation of additional peptides such as beta-amyloid. Deficiencies in IDE protein's function are linked with Alzheimer's disease and type 2 diabetes mellitus nevertheless mutations in the IDE gene have not been demonstrated to be causative for these diseases. Insulin-Degrading Enzyme localizes mainly to the cytoplasm however in some cell types it localizes to the extracellular space, cell membrane, peroxisome, and mitochondrion. In addition, IDE degrades amyloid formed by APP and IAPP. Furthermore, IDE plays a part in the degradation and clearance of naturally secreted amyloid beta-protein by neurons and microglia.

Legumain, also known as LGMN, is a cysteine endopeptidase which demonstrates strict specificity for hydrolysis of asparaginyl bonds. Furthermore, LGMN can also cleave aspartyl bonds slowly, in particular under acidic conditions. LGMN plays an essential role in the endosomal/lysosomal degradation system as the Legumain deficiency causes the accumulation of pro cathepsins B, H & L, another group of lysosomal cysteine proteases. Furthermore, over expression of LGMN in tumors is important for invasion/metastasis.

Prealbumin is a thyroid hormone-binding protein that transports thyroxine from the bloodstream to the brain. Prealbumin is a carrier protein which transports thyroid hormones in the plasma and cerebrospinal fluid, and also transports retinol (vitamin A) in the plasma. Transthyretin consists of a tetramer of identical subunits and is dominantly produced in the liver. Mutations in Prealbumin are related to amyloid deposition, affecting predominantly peripheral nerve and/or the heart. The diseases caused by mutations include amyloidotic polyneuropathy, euthyroid hyperthyroxinaemia, amyloidotic vitreous opacities, cardiomyopathy, oculoleptomeningeal amyloidosis, meningocerebrovascular amyloidosis, and carpal tunnel syndrome. Prealbumin is an indicator of protein-energy malnutrition since it has a circulating half life of 2 days and reacts swiftly to changes in nutritional status.

Cyclophilin-G is a member of the peptidyl-prolyl cis-trans isomerase (PPIase) family. PPIases catalyze the cis-trans isomerization of proline imidic peptide bonds in oligopeptides and speeds up the protein folding. PPIG catalyzes the cis-trans isomerization of proline imidic peptide bonds in oligopeptides and is involved in the folding, transport, and assembly of proteins. PPIG is localized to the nuclear speckles, a nuclear compartment rich in splicing factors, and cooperates with the splicing factors SC35 and pinin. Cyclophilin-G also takes part in the regulation of pre-mRNA splicing.

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.

METTL21A, which is a part of the methyltransferase superfamily, is a Protein-lysine methyltransferase that in vitro methylates HSPA1, HSPA5 and HSPA8.

Aspartoacylas or ASPA, is a protein, found in several tissues such as skeletal muscle, cerebral white matter, kidney, liver & lungs. ASPA is a homodimer that catalyses the deacetylation of Nacetylaspartic acid. In order to create L-aspartate & acetate.