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The 26S proteasome is a multicatalytic proteinase complex with a well ordered structure composed of two complexes- a 20S core and a 19S regulator. PSMD11 is a non-ATPase subunit of the 19S regulator. The 20S core is composed of four rings of 28 non-identical subunits; two rings are composed of 7 alpha subunits and two rings are composed of 7 beta subunits. The 19S regulator is composed of a base that contains six ATPase subunits and two non-ATPase subunits, and a lid that contains up to ten non-ATPase subunits. Proteasomes are spread throughout eukaryotic cells at a high concentration and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway. An indispensable function of a modified proteasome, the immunoproteasome, is the processing of class I MHC peptides.

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, 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.
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.

Cytosolic and membrane-bound types of GST are encoded by 2 different supergene families. There are 8 classes of the soluble cytoplasmic mammalian GST: alpha, kappa, mu, omega, pi, sigma, theta and zeta. The mu class of enzymes functions in the detoxification of electrophilic compounds, including carcinogens, therapeutic drugs, environmental toxins and products of oxidative stress, by conjugation with glutathione. The genes encoding the mu class of enzymes are arranged in a gene cluster on chromosome 1p13.3 and aare highly polymorphic. These genetic differences can change an individual's resistance to carcinogens and toxins as well as affect the toxicity and efficacy of certain drugs. Null mutations of this class mu gene have been linked with the rise in a number of cancers.

Gametocyte Specific Factor 1 (GTSF1) is a member of the UPF0224 (FAM112) family and contains 1 CHHC-type zinc finger. A key paralog of the GTSF1 gene is GTSF1L.

BDH2 is a member of the short-chain dehydrogenases/reductases (SDR) family. BDH2 protein has a significant part in the peripheral utilization of 3-hydroxybutyrate. BDH2 can convert high levels of circulating 3-hydroxybutyrate into acetoacetate due to cytoplasmic localization in high ratio of oxidized NAD+, the NAD+ dependence and the kinetic parameters.

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.

Placental alkaline phosphatase also known as PLAP is a membranal siaglycoprotein enzyme typicallyfoundin high concentration in syncytiotrophoblasts in the placenta amid the 3th trimester of gestation. The expression of PLAP was at firstconsidered to be onlyin the term placenta, though, a human PLAP-like variant has been found,thathas more than 85% homology with PLAP itself. PLAP is expressed strictly in normal term placenta, endocervix & fallopian tube and in ovarian and proximal gastrointestinal tumors. It is also widely expressed in germ cell tumors and more recently found in seminomas.

Fucosyltransferase 7 (FUT7) is a golgi stack membrane protein which is involved in the creation of sialyl-Lewis X antigens. The FUT7 protein leads the synthesis of the E-selectin-binding sialyl-Lewis X moiety. FUT7 catalyzes alpha-1,3 glycosidic linkages involved in the expression of sialyl Lewis X antigens.

Tubulin Polyglutamylase Complex Subunit 2 (TPGS2) is a component of the neuronal polyglutamylase complex, which takes part in post-translational addition of glutamate residues to C-terminal tubulin tails. Alternatively spliced transcript variants encoding multiple isoforms have been monitored for TPGS2.

Thrombin enzyme (Activated Factor IIa) is an important clotting promoter that controls the transformation of soluble fibrinogen to insoluble active fibrin strands. Thrombin is a coagulation protein and a serine protease (EC 3.4.21.5) that catalyzes many coagulation-related reactions. Thrombin triggers factor-XI, factor-V, Factor-XIII and factor-VIII. Thrombin endorses platelet activation, using activation of protease-activated receptors on the platelet. As a result of its high proteolytic specificity, thrombin has become an important biochemical protein. The thrombin cleavage site (Leu-Val-Pro-Arg-Gly-Ser) is widely used in linker regions of recombinant fusion protein constructs. After the purification of the fusion protein, thrombin is used to cleave between the Arginine and Glycine residues of the cleavage site, efficiently removing the purification tag from the protein of interest with a high degree of specificity.

AMPD2 is significant in purine metabolism by converting AMP to IMP. AMPD2 which functions as a homotetramer, is one of the three AMP deaminases shown in mammals. More than a few transcript variants encoding differentisoforms have been discovered for AMPD2.

PI3Ka plays a specific role in apoptosis in human colon cancer cells. Injection of neutralizing antibodies specific to PI3Ka into adenocarcinoma cells induced apoptosis, a response that was reverted by treating cells with caspase inhibitor. It was also shown that PI3Ka mediated phosphorylation of the p85a adapter reduces the lipid kinase activity of the heterodimer and this gives hints for PI3K-dependent signaling events not requiring production of 3’-phosphorylated phosphoinositides.
PI3Ka is a key regulator of the initiation of keratinocyte differentiation. A decrease in PI3Ka activity results in a loss of keratinocyte adhesion to the extracellular membrane and the initiation of early phase differentiation.

Collagen, a major component of the extracellular matrix, is a fibrous protein that provides tensile strength to tissues giving them structural integrity. Collagen and its derivative, gelatin, have been widely used in medical, pharmaceutical and consumer products for more than 100 years. The supply of these materials, created from animal remains, is both abundant and inexpensive. However, most formulations are not highly purified and have the potential to cause an inflammatory reaction in some product users. In addition, concerns have been raised over the last several years about the potential for contamination of bovine products with the agent that causes mad cow disease and its human variant, Creutzfeldt-Jakob Disease. Animal collagens are subject to extensive modifications that continue over the life of the molecule in the extracellular space. These differences influence both the extractability of collagens from tissue and the biophysical characteristics of these collagens. As a result, collagens isolated from tissues exhibit significant lot-to-lot variability and, as bulk materials, are often analytically intractable. Products that contain animal-derived collagen can induce potentially harmful inflammatory or immune responses in humans and pose risk of contamination with viruses or prions, potentially life-threatening pathogens. Recombinant collagens are essentially identical to the native collagen protein thereby reducing the risk of inflammation, immune response, and disease as compared to animal-sourced collagen.

Glucagon-like peptide-1 (GLP-1) is derived from the transcription product of the proglucagon gene. The major source of GLP-1 in the body is the intestinal L cell that secretes GLP-1 as a guthormone. The biologically active forms of GLP-1 are: GLP-1-(7-37) and GLP-1-(7-36)NH2.
GLP-1 secretion by L cells is dependent on the presence of nutrients in the lumen of the small intestine. The secretagogues (agents that causes or stimulates secretion) of this hormone include major nutrients like carbohydrate, proteinand lipid. Once in the circulation, GLP-1 has a half life of less than 2 minutes, due to rapid degradation by the enzyme dipeptidyl peptidase-4.
GLP-1 possesses several physiological properties that make it a subject of intensive investigation as a potential treatment of diabetes mellitus. The known physiological functions of GLP-1 include: Increases insulin secretion from the pancreas in a glucose-dependent manner, decreases glucagon secretion from the pancreas, increases beta cells mass and insulin gene expression, inhibits acid secretion and gastric emptying in the stomach, decreases food intake by increasing satiety.

Acyl-coenzyme A thioesterase 13 (ACOT13) belongs to the thioesterase subfamily of esterase family. ACOT13 is highly expressed in the kidney with moderate expression in the brain, liver and intestines. ACOT13 contains a hotdog-fold and is thought to co-localize with microtubules, possibly having a role in cellular proliferation events. Deletion of a segment of the q arm of chromosome 6 is linked to early onset intestinal cancer, suggesting the presence of a cancer susceptibility locus.

Cyclophilin B (also known as PPIB, peptidylpropyl isomerase B) is a cyclosporine-binding protein and is mainly located within the endoplasmic reticulum. It is associated with the secretory pathway and released in biological fluids. This protein can bind to cells derived from T- and B-lymphocytes, and may regulate cyclosporine A-mediated immunosuppression.

DLAT gene encodes component E2 of the multi-enzyme pyruvate dehydrogenase complex (PDC). PDC is located in the inner mitochondrial membrane and catalyzes the conversion of pyruvate to acetyl coenzyme A. The protein product of this gene, dihydrolipoamide acetyltransferase, takes acetyl groups created by the oxidative decarboxylation of pyruvate and transfers them to coenzyme A. Dihydrolipoamide acetyltransferase is the antigen for antimitochondrial antibodies which are found in about 95% of patients with the autoimmune liver disease primary biliary cirrhosis (PBC). In patients who suffer from this illness, activated T lymphocytes attack and destroy epithelial cells in the bile duct where this protein is abnormally distributed and overexpressed. PBC ultimately leads to cirrhosis and liver failure. Mutations in DLAT are also a cause of pyruvate dehydrogenase E2 deficiency which causes primary lactic acidosis in infancy and early childhood.

Signal-Regulatory Protein Alpha, SIRPA belongs to the signal-regulatory-protein (SIRP) family, as well as theimmunoglobulin super family. The members of the SIRP family are receptor-type transmembrane glycoproteins which areinvolved in the negative regulation of receptor tyrosine kinase-coupled signaling processes. SIRPA can bephosphorylated by tyrosine kinases. The phospho-tyrosine residues of this PTP have been shown to recruit SH2domain containing tyrosine phosphatases (PTP), and perform as substrates of PTPs. SIRPA take part insignal transduction mediated by a variety of growth factor receptors. CD47 has been shown to be a ligand forSIRPA.

IMPA2 is a member of the inositol monophosphatase family. IMPA2 catalyzes the dephosphoylration of inositol monophosphate and has a significant role in phosphatidylinositol signaling. IMPA2 can use the myo-inositol monophosphates, scylloinositol 1,4-diphosphate, glucose-1-phosphate, beta-glycerophosphate, and 2'-AMP as substrates. IMPA2 is a pharmacological target for lithium Li(+) action in brain. IMPA2 is considered to have a role in schizophrenia and bipolar disorder.

GARS is an (alpha)2 dimer which is a member of the class II family of tRNA synthetases. GARS is a glycyl-tRNA synthetase, one of the aminoacyl-tRNA synthetases which charge tRNAs with their cognate amino acids. GARS catalyzes the attachment of glycine to tRNA(Gly). In addition, GARS is able to produce diadenosine tetraphosphate (Ap4A), which is a universal pleiotropic signaling molecule required for cell regulation pathways, by direct condensation of two ATPs. GARS has been demonstrated to be a target of autoantibodies in the human autoimmune diseases, polymyositis or dermatomyositis.

Gastrokine 3 (GKN3P) is a Pseudogene, which May inhibit gastric epithelial cell proliferation.

Glycine-N-Acyltransferase-Like 2 (GLYATL2) is a part of the glycine N-acyltransferase family expressed mainly in salivary gland and trachea. GLYATL2 is a mitochondrial acyltransferase that transfers the acyl group to the N-terminus of glycine. GLYATL2 conjugates numerous substrates, like arachidonoyl-CoA and saturated medium and longchain acyl-CoAs ranging from chain-length C8:0-CoA to C18:0-CoA, to form a variety of N-acylglycines. GLYATL2 also shows a preference for monounsaturated fatty acid oleoyl-CoA (C18:1-CoA) as an acyl donor.

Cytosolic and membrane-bound types of GST are encoded by 2 different supergene families. There are 8 classes of the soluble cytoplasmic mammalian GST: alpha, kappa, mu, omega, pi, sigma, theta and zeta. The mu class of enzymes functions in the detoxification of electrophilic compounds, including carcinogens, therapeutic drugs, environmental toxins and products of oxidative stress, by conjugation with glutathione. The genes encoding the mu class of enzymes are arranged in a gene cluster on chromosome 1p13.3 and aare highly polymorphic. These genetic differences can change an individual's resistance to carcinogens and toxins as well as affect the toxicity and efficacy of certain drugs. Null mutations of this class mu gene have been linked with the rise in a number of cancers.