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Macrophage Scavenger Receptor 1, also known as MSR1 is a member of the class A macrophage scavenger receptors, which comprises three different types 1, 2 and 3 generated by alternative splicing. Furthermore, these receptors or isoforms are macrophage-specific trimeric integral membrane glycoproteins and have been implicated in many macrophage-associated physiological as well as pathological processes which include atherosclerosis, Alzheimer's disease, and host defense.

Oncostatin M is a member of a cytokine family that includes leukemia-inhibitory factor, granulocyte colony-stimulating factor, and interleukin 6. This gene encodes a growth regulator which inhibits the proliferation of a number of tumor cell lines. It regulates cytokine production, including IL-6, G-CSF and GM-CSF from endothelial cells.

MMADHC is a mitochondrial protein which takes part in an early step of vitamin B1 2 metabolism. Vitamin B12 (cobalamin) is vital for regular development and existence in humans. Mutations in MMADHC can result in methylmalonic aciduria and homocystinuria type cblD, a cobalamin metabolism syndrome which is characterized by decreased levels of the coenzymes methylcobalamin and adenosylcobalamin.

Apoptosis-Inducing Factor, Mitochondrion-Associated, 1 (AIFM1) is a mitochondrial protein which translocates to the nucleus once apoptosis has been initiated. AIFM1 causes DNA fragmentation and chromatin condensation and also triggers the release of cytochrome c and caspase-9 from mitochondria. Bcl-2 overexpression prevents the release of AIFM1 from mitochondria, but doesn’t block its apoptogenic activity.

Peroxisome proliferators are non-genotoxic carcinogens which are purported to exert their effect on cells through their interaction with members of the nuclear hormone receptor family termed peroxisome proliferators activated receptors (PPARs). Nuclear hormone receptors are ligand-dependent intracellular proteins that stimulate transcription of specific genes by binding to specific DNA sequences following activation by the appropriate ligand. Studies indicate that PPARs are activated by peroxisome proliferators such as clofibric acid, nafenopin, and WY-14,643, as well as by some fatty acids.

GABARAP is a ligand-gated chloride channel that mediates inhibitory neurotransmission. GABARAP is highly positively charged in its N-terminus and shares sequence similarity with light chain-3 of microtubule-associated proteins 1A and 1B. GABARAP clusters neurotransmitter receptors by mediating interaction with the cytoskeleton.

Matrix metalloproteinase-7 (MMP-7) also known as matrilysin and PUMP (EC 3.4.24.23) cleaves a number of substrates including collagen types IV and X, elastin, fibronectin, gelatin, laminin and proteoglycans. MMP-7 is closely related to the stromelysin family members but is encoded by a different gene. MMP-7 is the smallest of all the MMPs consisting of a pro-peptide domain and a catalytic domain. It lacks the hemopexin-like domain common to other members of the MMPs. MMP-7 is secreted as a 28 kDa proenzyme and can be activated in vitro by organomercurials and trypsin and in vivo by MMP-3 to a 18 kDa active MMP-7 enzyme. Once activated, MMP-7 can activate pro-MMP-1 and pro-MMP-9 but not pro-MMP-2. MMP-7 is widely expressed having been reported in elevated levels in cycling endometrium as well as in colorectal cancers and adenomas, hepatocellular carcinomas, rectal carcinomas, and approximately 50% of gliomas.

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.

VCPKMT is a member of the methyltransferase superfamily. VCPKMT is a protein-lysine N-methyltransferase which specifically trimethylates 'Lys-315' of VCP/p97; this alteration reduces VCP ATPase activity.

Synaptobrevin-2 or VAMP2 is a protein that has a proline-rich N-terminal part, highly conserved hydrophilic domain, a transmembrane anchor and a C-terminal.VAMP2 found in the transmembrane region of the cell, in the cytoplasmic surface of the synaptic vesicle. The protein is mainly found in the Langerhans islets in the pancreas and glomerular cells in the kidney. A SNARE complex is created within the protein’s N-terminal domain and the target membrane-associated T.

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.

Carcinoembryonic Antigen-Related Cell Adhesion Molecule 8 (CEACAM8) is a cell surface glycoprotein which takes part in cell adhesion in a calciumindependent manner.CEACAM8mediates heterophilic cell adhesion with other carcinoembryonic antigen-related celladhesion molecules (CEACAM6 for example).CEACAM8main role is cell migration,cell adhesion, and pathogen binding.CEACAM-8 isexpressed mainly on the surface of human peripheral blood eosinophils isolated from healthy individuals andused as granulocyte marker.

Maltose Binding Protein (MBP) is a part of the maltose/maltodextrin system of Eschericia coli bacteria, which is responsible for the uptake and efficient catabolism of maltodextrins. It is a complex regulatory and transport system involving many proteins and protein complexes.
Maltose binding protein MalE,MBP, is part of the maltodextrin transport system in E. coli. The maltodextrins diffuse through the LamB pore located in the outer membrane into the periplasm. The sugar is bound to MalE which prevents it to diffuse back outside. MalE passes the sugar to a complex of MalF and MalG in the cytoplasmic membrane where active tranport is mediated by the ATPase MalK. MBP molecular weight is 40,622 dalton. There are two domains in the protein with similar secondary structure (central pleated sheets are surrounded by helices) . The domains are connected by three bridges, between the domains is a deep groove in which the sugar is bound. All hydroxyl groups of the sugar are fixed by sidechains of the protein by hydrogen bonds. Some water molecules are part of the hydrogen bridge network.

Proteasome assembly chaperone 2 (PSMG2) stimulates assembly of the 20S proteasome as part of a heterodimer with PSMG1. The PSMG1-PSMG2 heterodimer binds to the PSMA5 and PSMA7 proteasome subunits and promotes compilation of the proteasome alpha subunits into the heteroheptameric alpha ring and prevents alpha ring dimerization. PSMG2 is widely expressed with highest levels in the lung, brain and colon. It is moderately expressed in the muscle, stomach, spleen and heart, and weakly expressed in the small intestine, pancreas and liver. It is also highly expressed in hepatocellular carcinomas with low levels in surrounding liver tissue.

BAG3 Inhibits the chaperone activity of HSP70/HSC70 by promoting substrate release. BAG3 has anti-apoptotic activity. BAG proteins participate with Hip for their binding to Hsc70/Hsp70 ATPase domain and encourage substrate release. BAG proteins have about 45 amino acid BAG domain close to the C terminus however they differ noticeably in their N-terminal regions. BAG3 includes a WW domain in the N-terminal region and a BAG domain in the C-terminal region. The BAG domains of BAG1, BAG2, and BAG3 interact particularly with the Hsc70 ATPase domain in vitro and in mammalian cells. They bind with high affinity to the ATPase domain of Hsc70 and inhibit its chaperone activity in a Hip-repressible manner. BAG3 plays a role as a protein-refolding cochaperone of the bcl2 binding protein BAG family and as upregulated in response to persistent stress of cellular calcium balance dysregulation. BAG3 has been shown to diminish stress-induced apoptosis.

The proteasome is a multicatalytic proteinase complex with a highly assembled ring-shaped 20S core structure which is composed of 4 rings of 28 non-identical subunits, 2 rings are composed of 7 alpha subunits and 2 rings are composed of 7 beta subunits. Proteasomes are found throughout eukaryotic cells at a high concentration and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway. PSMA7 is part of the peptidase T1A family, that is a 20S core alpha subunit. PSMA7 interacts particularly with the hepatitis B virus X protein, a protein critical to viral replication. PSMA7 is involved in regulating hepatitis virus C internal ribosome entry site activity that is crucial for viral replication. PSMA7 is in charge for regulating the hypoxia-inducible factor-1alpha, a transcription factor important for cellular responses to oxygen tension. PSMA7 is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. PSMA7 interacts specifically with two subdomains of HIF-1alpha and inhibited the transactivation function of HIF-1alpha under both normoxic and hypoxia-mimicking conditions.

Platelet factor-4 is a 70-amino acid protein that is released from the alpha-granules of activated platelets and binds with high affinity to heparin. Its major physiologic role appears to be neutralization of heparin-like molecules on the endothelial surface of blood vessels, thereby inhibiting local antithrombin III activity and promoting coagulation. As a strong chemoattractant for neutrophils and fibroblasts, PF4 probably has a role in inflammation and wound repair. Oncostatin-A is a member of the CXC chemokine family. Human PF4 is used for the proof of heparin-induced thrombocytopenia. Furthermore it is used as an inhibitor in the angiogenesis during tumor therapy.

The human Lymphocyte Antigen 6 Complex Locus G6F (LY6G6F) protein is a type I transmembrane protein belonging to the immunoglobin (Ig) superfamily, which contains cell-surface proteins involved in the immune system and cellular recognition. The LY6G6F protein has a role in the downstream signal transduction pathways involving GRB2 and GRB7.

PSMB1 is part of the proteasome B-type family, also identified as the T1B family, that is a 20S core beta subunit. PSMB1 is tightly linked to the TBP (TATA-binding protein) gene in human and in mouse, and is transcribed in the opposite orientation in both species.The main function of PSMB1 is its degradation activity of unnecessary or damaged proteins by proteolysis. PSMB1 is a multicatalytic proteinase complex which is characterized by its ability to cleave peptides with arg, phe, tyr, leu, and glu adjacent to the leaving group at neutral or slightly basic ph. the proteasome has an atp-dependent proteolytic activity.

PSMB5 belongs to the proteasome B-type family that has a 20S core beta subunit in the proteasome. This catalytic subunit is not present in the immunoproteasome and is substituted by catalytic subunit 3i (proteasome beta 8 subunit). A fundamental function of a modified proteasome, the immunoproteasome, is the processing of class I MHC peptides. PSMB5 exhibits an ATP dependent proteolytic activity and is involved in an ATP/ubiquitin dependent non lysosomal proteolytic pathway.

Anamorsin, ( CIAPIN) is a member of anamorsin family. CIAPIN mainly expressed in the cytoplasm of liver, pancreas and heart tissue cells and does not show any homology to known apoptosis regulatory molecules of the Bcl-2 or CASP families, or to signal transduction molecules. CIAPIN1 Expression is reliant on growth factor stimulation. It is a ubiquitously expressed protein, and when it is overexpressed, it grants apoptotic resistance.

GPN-loop GTPase 1 (GPN1) is a member of the GPN-loop GTPase family. GPN1 is a guanosine triphosphatase enzyme which has a role in DNA repair and may function in activation of transcription. Small GTPases, which share a biochemical mechanism, act as binary molecular switches and function in the cell is nucleocytoplasmic transport of both proteins and RNA. In addition, GPN1 establishs an interface between the RNA polymerase II enzyme and chaperone/scaffolding protein, proposing that it is essential to connect RNA polymerase II to regulators of protein complex formation. GPN1 may also be involved in nuclear localization of XPA.

Transmembrane protein PRRT2 holds a proline-rich domain in its N-terminal half. PRRT2 is known to be primarily expressed in brain and spinal cord in embryonic and postnatal stages. Alterations in this gene are the cause for paroxysmal kinesigenic dyskinesia. PRRT2 mutations were found in nearly 30% of sporadic PKC patients.

Axin interactor, dorsalization-associated (AIDA) operates as a ventralizing factor during embryogenesis. AIDA inhibits axin-mediated JNK activation by binding axin and disrupting axin homodimerization. That in turn antagonizes a Wnt/beta-catenin-independent dorsalization pathway activated by AXIN/JNK-signaling.