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Alpha 1 ACT is an early-stage acute-phase plasma protein and a serpin that preferentially inactivates chymotrypsin, cathepsin G, and chymase. Alpha-1-ACT, a serine protease inhibitor, is tightly associated with amyloid plaques in Alzheimer's disease (AD) and in normal aged human and monkey brain.
Regulation of the serine proteases and serine protease inhibitors plays an important role in neuromuscular differentiation. Prostate specific antigen (PSA), a chymotrypsin-like serine protease, is predominantly complexed to Alpha-1-ACT.

Dihydrofolate reductase (DHFR) is an enzyme that reduces dihydrofolic acid to tetrahydrofolic acid, with NADPH as electron donor that can be converted to the kinds of tetrahydrofolate cofactors applied in 1-carbon transfer chemistry. DHFR converts dihydrofolate into tetrahydrofolate, which is a methyl group shuttle required for the de novo synthesis of purines, thymidylic acid, and specific amino acids. Even though the functional DHFR gene is mapped to chromosome 5, numerous intronless processed pseudogenes or dihydrofolate reductase-like genes are identified on separate chromosomes.
DHFR deficiency is associated with megaloblastic anemia.
DHFR knockdown plays a role in the anticancer activity of 2-hydroxyoleic acid.
DHFR gene insertion/deletion polymorphism is linked to variation in serum and red blood cell folate concentrations in women.

Histidine NADH Dehydrogenase Fe-S Protein 5 (NDUFS5) belongs to the NADH dehydrogenase (ubiquinone) iron-sulfur protein family. NDUFS5 is a subunit of the mitochondrial membrane respiratory chain NADH dehydrogenase (Complex I), which doesn’t take part in catalysis. Complex I is transferring the electrons from NADH to the respiratory chain.

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.

Interleukin-8 (IL-8) is a chemokine produced by macrophages and other cell types such as epithelial cells. It is also synthesized by endothelial cells, which store IL-8 in their storage vesicles, the Weibel-Palade bodies. When first encountering an antigen, the primary cells to encounter it are the macrophages who phagocytose the particle. Upon processing, they release chemokines to signal other immune cells to come in to the site of inflammation. IL-8 is one such chemokine. It serves as a chemical signal that attracts neutrophils at the site of inflammation, and therefore is also known as Neutrophil Chemotactic Factor.

Family with Sequence Similarity 84, Member B (FAM84B) coprecipitated with a downstream effector of RAS, CRAF. Binding of FAM83B with CRAF interrupted CRAF/14-3-3 interactions and increased CRAF membrane localization, causing elevated MAPK and mammalian target of rapamycin (mTOR) signaling. FAM84B is an oncogene and possibly represents a new target for therapeutic intervention.

C8, a component of the complement system consists of three polypeptides C8A, C8B and C8G and takes part in the formation of Membrane Attack Complex (MAC). Patients with C8 deficiency are exposed to several bacteria infections. C8G, a member of the lipocalin family and calycin superfamily, is a secreted protein that can bind retinol. C8G is created in the liver, monocytes and fibroblast and has a role in clearing pathogens from an infected host.

Transforming growth factor betas (TGF Betas) mediate many cell-cell interactions that occur during embryonic development. Three TGF Betas have been identified in mammals. TGF Beta 1, TGF Beta 2 and TGF Beta 3 are each synthesized as precursor proteins that are very similar in that each is cleaved to yield a 112 amino acid polypeptide that remains associated with the latent portion of the molecule.

Ciliary Neurotrophic Factor Receptor, also known as CNTFR is a member of the type I cytokine receptor family. CNTFR binds to CNTF. The alpha subunit provides the receptor specificity. Sole nucleotide polymorphisms in CNTFR has been associated with variations in muscle strength, in addition to early onset of eating disorders.

This gene is a member of the EPO/TPO family and encodes a secreted, glycosylated cytokine composed of four alpha helical bundles. The protein is found in the plasma and regulates red cell production by promoting erythroid differentiation and initiating hemoglobin synthesis. This protein also has neuroprotective activity against a variety of potential brain injuries and antiapoptotic functions in several tissue types.

GDNF Family Receptor Alpha 3 (GFRA3) belongs to the GDNF receptor family. GFRA3 creates a signaling receptor complex with RET tyrosine kinase receptor and binds the ligand, artemin (ARTN).

AGXT is expressed only in the liver and its protein is localized mostly in the peroxisomes, where it is involved in glyoxylate detoxification. Mutations in the AGXT gene, some of which alter subcellular targetting, have been linked to type I primary hyperoxaluria.

Ornithine aminotransferase is a key enzyme in the pathway that converts arginine and ornithine into the major excitatory and inhibitory neurotransmitters glutamate and GABA. Ornithine aminotransferase (OAT) is a 49kDa nucleus-encoded protein imported into mitochondria to give the mature 48kDa OAT polypeptide. It is found in humans, animals, insects, plants and microorganisms. The OAT has a sex-differential expression in the mouse kidney. OAT plays central physiological roles in amino acid metabolism. OAT shows a large structural and mechanistic similarity to other enzymes from the subgroup III of aminotransferases that transfer an amino group from a carbon atom which doesn’t carry a carboxyl function. OAT is vital for nitrogen recycling from arginine but not for the stress-induced proline accumulation. OAT enzyme deficiency causes the autosomal recessive eye disease Gyrate Atrophy.

GST family of enzymes comprises a long list of cytosolic, mitochondrial, and microsomal proteins that are 45-55 kDa (dimer form) size and are capable of multiple reactions with a multitude of substrates, both endogenous and xenobiotic. GST catalyses the conjugation of reduced glutathione meaning the sulfhydryl group, to electrophilic centers on a wide variety of substrates. This activity is useful in the detoxification of endogenous compounds such as peroxidised lipids, as well as the metabolism of xenobiotics. GST binds toxins and function as transport protein. Glutathione S-transferase is used to create the so-called ''GST gene fusion system''. The GST is used to purify and detect proteins of interest. In a GST gene fusion system, the GST sequence is incorporated into an expression vector alongside the gene sequence encoding the protein of interest. Induction of protein expression from the vector''s multiple cloning sites results in expression of a fusion protein - the protein of int

MAT2A is an important enzyme in cellular metabolism and catalyzes the formation of S-adenosylmethionine (SAMe) from L-methionine and ATP. MAT2A is expressed in extrahepatic tissues. In liver, MAT2A expression associates with growth, dedifferentiation, and cancer. NF-kappa B and AP-1 are necessary for basal MAT2A expression in HepG2 cells and mediate the increase in MAT2A expression in response to TNF-alpha. Up-regulation of MAT2A provides growth improvement and s-adenosylmethionine and methylthioadenosine thus can block mitogenic signaling in colon cancer cells. Lower expression of both MAT2A and MAT2beta and interfere with leptin signaling in liver cancer cells.

Avidin is a tetrameric protein of 4 identical subunits (homotetramer) which can bind to biotin with a high degree of affinity and specificity. The estimated molecular weight of Avidin in its tetrameric form is between 66-69 kDa. Avidin is produced in the oviducts of birds, reptiles and amphibians and is subsequently deposited in the whites of their eggs. In the chicken egg white, avidin makes up roughly 0.05% of total protein (approximately 1.8 mg per egg). 10% of Avidin’s molecular weight is ascribed to carbohydrate content which is composed of 4-5 mannose and 3 N-acetylglucosamine residues. Avidin has at least three distinctive oligosaccharide structural type which are similar in structure and composition. The dissociation constant (KD) of avidin is approximately 10-15M, making it one of the strongest known non-covalent bonds.

Fc fragment of IgE, high affinity I, receptor for; alpha polypeptide (FCER1A) binds to the Fc region of immunoglobulins epsilon. FCER1A is a high affinity receptor. In addition FCER1A is responsible for starting the allergic response. Binding of allergen to receptor-bound IgE leads to cell activation and the release of mediators such as histamine which is responsible for the manifestations of allergy. This receptor is contains of an alpha subunit, a beta subunit, and two gamma subunits. FCER1A stands for the alpha subunit. Among the diseases associated with FCER1A are mast-cell leukemia, and allergic asthma.

Fibronectin Leucine Rich Transmembrane Protein 2 or FLRT2 is a glycoprotein, part of the 3 FLRT glycoproteins (fibronectin, leucine rich repeat, transmembrane). This protein can be found in apparent areas of the brain and additional tissues. The genes of FLRT1 & FLRT3 extracellular domain has about 47% similarity to FLRT2. A domain of fibronectin in FLRT1, FLRT3 & FLRT2 can be bound to epidermal growth factor receptors.

VTI1B (v-SNARE) mediates vesicle transport pathways via interactions with t-SNAREs on the target membrane. These interactions are meant to facilitate aspects of the specificity of vesicle trafficking and to stimulate fusion of the lipid bilayers. VTI1B may be involved in increased secretion of cytokines connected with cellular senescence.

Thyroid Peroxidase (TPO) represents one of the main autoantigenic targets in autoimmune thyroid disease of humans. Its identity with the formerly so-called `microsomal antigen` has been shown several years ago. As an integral membrane glycoprotein it is restricted to the apical plasma membrane of the follicular epithelial cells and comprises two identical subunits of approx. 100 kDa molecular weight. The hemoprotein TPO plays a key role in the thyroid hormone biosynthesis by catalysing both the iodination of tyrosyl residues and the coupling of iodotyrosyl residues in thyroglobulin (TG) to form precursors of the thyroid hormones T4 and T3.

Alpha 1-microglobulin (A1M) is a lipocalin superfamily member (kernal lipocalins). A1M is a low molecular weight protein component of plasma. A1M is distributed in plasma and extravascular compartments of all organs. Alpha-1 Microglobulin is found in mammals, birds, amphibians and fish. The primary sites of A1M synthesis are the liver and the kidney. Around the opening of the lipocalin pocket three lysyl residues are situated; those residues carry yellow-brown modification derived from the binding and degradation of heme and kynurenin (a tryptophan metabolite). A1-Microglobulin’s reductase and dehydrogenase have broad biological substrate specificity properties due to its’ free cysteine side-chain which is located in a flexible loop. Alpha-1-microglobulin is glycosylated by three separate carbohydrate chains: two complex carbohydrates which are N-linked to asparagines at residues 17 and 96, and the other simple carbohydrate which is O-linked to threonine at position 5. The carbohydrates comprise 22% of the total molecular mass of the protein. The glycosylation varies between species.
A1M exists in two forms- a free form and complexed to other macromolecules: in humans- complexed to immunoglobulin A (IgA), in rat- complexed to alpha-1-inhibitor-3. Free A1M is exceptionally heterogeneous in charge (therefore also known as protein HC), and is found tightly linked to a chromophore. The free Alpha-1-microglobulin is a monomeric protein composed of one 188 residue polypeptide and contains three cysteines, two of which (residues 75 and 173) form a conserved intra-molecular disulphide link. The chromophoric group is covalently bound to the free cysteine residue at position 34. A1M binds retinol as a major ligand, but this is probably distinct from its covalent chromophore.
Half of all human plasma A1M (approximately 0.03mg/ml) forms a 1:1 complex with about 5% of plasma immunoglobulin A. The resulting macromolecular complexes’ molecular weight is 200000, and a plasma concentration of 0.3mg/ml. The complex can exhibit both antibody activity and affect many of the biological actions of free Alpha-1-microglobulin.
Alpha-1-microglobulin was first discovered in pathological human urine.
It was suggested that A1M might be involved in tissue defense against reactive oxygen species, oxidation by heme and kynurenin. Evidence also suggests that A1M functions in the regulation of the immune system. Other functions include inhibition of stimulation of cultured lymphocytes by protein antigens; induction of cell division of lymphocytes, a mitogenic effect that can either be enhanced or inhibited by the action of other plasma components; inhibition of neutrophil granulocyte migration in vitro; and inhibition of chemotaxis.

Apolipoprotein-D is mainly associated with high density lipoproteins in human plasma. Apolipoprotein-D is an atypical apolipoprotein and, based on its primary structure, Apolipoprotein-D is a member of the lipocalin family. Lipocalins adopt a beta-barrel tertiary structure and transport small hydrophobic ligands. Apolipoprotein-D binds cholesterol, progesterone, pregnenolone, bilirubin and arachidonic acid.
Apolipoprotein-D is expressed in numerous tissues having high levels of expression in spleen, testes and brain. Apolipoprotein-D is present at high concentrations in the cyst fluid of women with gross cystic disease of the breast, a condition associated with increased risk of breast cancer. Apolipoprotein-D accumulates in regenerating peripheral nerves and in the cerebrospinal fluid of patients with neurodegenerative conditions, such as Alzheimer's disease. Apolipoprotein-D participates in maintenance and repair within the central and peripheral nervous systems. Apolipoprotein-D is a multi-ligand, multi-functional transporter and transports a ligand from 1 cell to another within an organ, scavenge a ligand within an organ for transport to the blood or could transport a ligand from the circulation to specific cells within a tissue.