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Meprin A subunit beta (MEP1B) belongs to the astacin family of zinc endopeptidases 1, 2. MEP1B is a disulfide-linked, tetrameric metalloendopeptidase in renal brush border membranes. MEP1B is highly regulated, secreted cell-surface metalloendopeptidase, which is amply expressed in the kidney and intestine.

AIMP1 (EMPA2 or p43) is a cytokine that is specifically induced by apoptosis, and it is involved in the control of angiogenesis, inflammation, and wound healing. The release of the AIMP1 cytokine renders the tumor-associated vasculature sensitive to tumor necrosis factor. Furthermore, AIMP1 is involved in the stimulation of inflammatory responses after proteolytic cleavage in tumor cells.

Serpin Peptidase Inhibitor, Clade A Member 9, also known as serpin A9, belongs to the Serpin superfamily of serine protease inhibitors. Serpins are the most extensively distributed superfamily of protease inhibitors which use a conformational modification to inhibit target enzymes. Serpins are known to inhibit serine proteases as well as inhibiting caspases in addition to papain-like cysteine proteases. Serpins are conformational labile and numerous of the disease-linked mutations of serpins outcome in misfolding or in pathogenic, inactive polymers. serpin A9 demonstrates inhibition towards trypsin, thrombin, as well as plasmin and binds DNA and heparin.

SPIN1 is a member of the SPIN/STSY family. SPIN1 is localized to nucleus, and expressed in several tissues and cells. SPIN1 takes part in cell-cycle regulation in the course of the transition from gamete to embryo.

Endoglin is a type I membrane glycoprotein located on cell surfaces and is part of the TGF beta receptor complex.
The Endoglin protein consists of a homodimer of 180 kDA with disulfide links. Endoglin has been found on endothelial cells, activated macrophages, fibroblasts, and smooth muscle cells. Furthermore, Endoglin has been found to be part of the TGF-beta1 receptor complex. Endoglin thus may be involved in the binding of TGF-beta1, TGF-beta3, activin-A, BMP-2, and BMP-7. Beside TGF-beta signaling endoglin may have other functions. It has been postulated that endoglin is involved in the cytoskeletal organization affecting cell morphology and migration. Endoglin has a role in the development of the cardiovascular system and in vascular remodeling. Endoglin expression is regulated during heart development . Experimental mice without the endoglin gene die due to cardiovascular abnormalities.

ETNK2 belongs to theethanolaminekinase family which catalyzes the 1st step of PtdEtn biosynthesis via the cytidine diphosphate.

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.

Killer cell immunoglobulin-like receptor 2DL4, also known as KIR2DL4 is part of the killer cell Ig-like receptor (KIR) family. KIR proteins with the long cytoplasmic domain transduce inhibitory signals through an immune tyrosine-based inhibitory motif (ITIM), whereas KIR proteins which contain the short cytoplasmic domain, lack the ITIM motif and as a substitute associate with the TYRO protein tyrosine kinase binding protein to transduce activating signals. KIR2DL4 stimulates NK cells to produce IFN-gamma and stimulation with IL-2 upregulates cell surface expression on CD56dimcells and leads to the inhibition of the cytolytic NK cell function.

V-Set Domain Containing T Cell Activation Inhibitor 1, also known as VCTN1, is part of the B7 costimulatory protein family. Proteins in this family are located on the surface of antigen-presenting cells and interact with ligand bound to receptors on the surface of T cells. High level of the encoded protein has been associated with tumor progression. VCTN1 also takes part in promoting epithelial cell transformation.

Matrix metalloproteinase-2 (MMP-2) 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).

Zinc-alpha-2-glycoprotein (ZAG) is found in body fluids such as serum, sweat, and seminal and breast cyst fluids. It is identical in amino acid sequence to tumor-derived lipid mobilizing factor (LMF), a protein associated with the dramatic loss of adipose body stores in cancer cachexia, and has been shown to stimulate lipolysis by adipocytes in vivo and in vitro. A role for ZAG has been proposed in the regulation of body weight, and age-dependent changes in genetically influenced obesity, and also it regulates melanin production by normal and malignant melanocytes. It has also recently been classified as a novel adipokine in that it is produced by both white and brown fat adipocytes and may act in a local autocrine fashion in the reduction of adiposity in cachexia. Controlling ZAG/LMF's activity could be life-saving in the management of certain cancers and other cachexiainducing conditions, and its possible normal role in body fat store homeostasis is deserving of understanding in its own right. ZAG exhibits a class I major histocompatibility complex (MHC) fold but is a soluble protein rather than being anchored to plasma membranes and does not associate with alpha-2-microglobulin in humans. Like antigen-presenting MHC class I proteins, ZAG has an open apical groove, and X-ray crystallography of human derived ZAG revealed an unidentifiable electron density in a similar position to that occupied by antigenic peptides in classical MHC proteins and glycolipids in isoforms of CD1. This presumptive ligand is not a peptide, and the groove is too small to hold a glycolipid such as is presented by CD1 isoforms. By analogy with all other MHC class I-related proteins that have an open apical groove [some do not ], occupancy by a ligand is probably crucial to ZAG's biological function. Despite all of the structural and biochemical evidence that ZAG binds a ligand, none has so far been found by extraction from protein isolated from biological fluids. This difficulty could be because the ligand is labile, heterogeneous, or readily lost during purification procedures. Knowing more about how ZAG interacts with the compounds it has been found to bind, both natural and artificial, will inform searches for the elusive ligand(s) and its/their role in ZAG's signaling function.

Synaptotagmin-1(SYT1) is a member of the synaptotagmin family, which contains two C2 domains. The synaptotagmins are integral membrane proteins of synaptic vesicles assumed to function as Ca(2+) sensors in the process of vesicular trafficking and exocytosis. SYT1 is the principal regulator responsible for allowing the human brain to release neurotransmitters. SYT1 may have a regulatory role in the membrane interactions during trafficking of synaptic vesicles at the active zone of the synapse. SYT1 binds acidic phospholipids with a specificity which entails the presence of both an acidic head group and a diacyl backbone. SYT1 can also bind to at least 3 additional proteins in a Ca2+-independent manner; these being neurexins, syntaxin and AP2.

PSMG3 is a chaperone protein that promotes assembly of the 20S proteasome. PSMG3 may cooperate with PSMG1-PSMG2 heterodimers to coordinate the correct assembly of proteasomes. PSMG3 interacts with PSMG4, as well as directly with alpha and beta subunits of the 20S proteasome but dissociates prior to the formation of half-proteasomes, probably upon recruitment of POMP.

MAPK11 belongs to the MAP kinase family and is most associated with p38 MAP kinases (MAPKs). MAPKs are activated mainly as a reaction to cellular stress and inflammatory cytokines, and inhibitors that target the MAPK14 and MAPK11 have demonstrated ability to cure inflammatory disease. MAPK11 cooperates with HDAC3 and Promyelocytic leukemia protein and takes part in a signal transduction pathway which is activated by alterations in the osmolarity of the extracellular environment, by environmental stress, or by cytokines.

EPGN is an EGF-related polypeptide growth factor that signals through the ErbB receptor-1. EPGN is produced in numerous tissues, including the testis, liver, heart and in certain tumor cells. EPGN is mitogenic for fibroblasts and epithelial cells. Human EPGN is originally synthesized as a glycosylated 14.7 kDa transmembrane precursor protein, which is processed by proteolytic cleavage to produce a mature soluble sequence.

ArsA Arsenite Transporter, ATP-Binding, Homolog 1 (ASNA1) is a part of the arsA ATPase family. ASNA1 is the human homolog of the bacterial arsA gene. ArsA ATPase is the catalytic component of a multisubunit oxyanion pump In E.coli, which is in charge for resistance to arsenicals and antimonials. ASNA1 is also a main component of a transmembrane domain (TMD) recognition complex (TRC) which is involved in the post-translational delivery of tail-anchored (TA) proteins from the cytosol to the endoplasmic reticulum (ER).

PCNA is located in the nucleus and is a cofactor of DNA polymerase delta. PCNA acts as a homotrimer and helps elevate the processivity of leading strand synthesis during DNA replication. In reaction to DNA damage, PCNA is ubiquitinated and takes part in the RAD6-dependent DNA repair pathway. 2 transcript variants encoding the same protein have been found for PCNA gene. Pseudogenes of this PCNA gene have been described on chromosome 4 and on the X chromosome. PCNA is expressed during late G1- phase, S-phase of mitosis and persists until the end of the M-phase because of its long biological half-life. PCNA is induced by UV irradiation.

PEBP1 (Phosphatidylethanolamine binding protein 1) belongs to the phosphatidylethanolamine-binding protein family and a serine protease inhibitor that inhibits thrombin, neuropsin. PEBP1 plays a key modulatory part in several protein kinase signaling cascades. PKC phosphorylates PEBP1, resulting in the release of Raf-1 and activation of MEK and ERK. PEBP1 is expressed in many tissues and implicated in the regulation of such physiological processes as membrane biosynthesis, spermatogenesis, neural development, and metastasis suppression.
PEBP1 binds ATP, opioids and phosphatidylethanolamine, however it has lower affinity for phosphatidylinositol and phosphatidylcholine. PEBP1 may also be involved in the function of the presynaptic cholinergic neurons of the CNS. PEBP1 increases the production of choline acetyltransferase although not acetylcholinesterase. Furtheremore, PEBP1 functions in potentially sequestering toxic compounds, including locostatin which may have harmful effects on cells.
Loss of PEBP1 expression may have a significant role as prognostic marker in Gastrointestinal stromal tumors. In addition, PEBP1 is found differentially expressed in the Wernicke's Area from schizophrenia patients. PEBP1 is also, an invasion suppressor protein in nasopharyngeal carcinoma.

GIPC2 is a 315 aa protein which is restricted to the cytoplasm and holds one PDZ domain. GIPC2 is expressed in large quantities in colon and kidney and in small quantities in adult liver. GIPC2 has a vital part in human gastric cancer by control of growth factor signaling or cell adhesion.

GH is a member of the somatotropin/prolactin family of hormones which play an important role in growth control. The gene, along with four other related genes, is located at the growth hormone locus on chromosome 17 where they are interspersed in the same transcriptional orientation; an arrangement which is thought to have evolved by a series of gene duplications. The five genes share a remarkably high degree of sequence identity. Alternative splicing generates additional isoforms of each of the five growth hormones, leading to further diversity and potential for specialization. This particular family member is expressed in the pituitary but not in placental tissue as is the case for the other four genes in the growth hormone locus. Mutations in or deletions of the gene lead to growth hormone deficiency and short stature.

Histone is vastly alkaline protein exists in eukaryotic cell nuclei which set and direct the DNA into structural units named nucleosomes. 5 key families of histones are: H1/H5, H2A, H2B, H3, including H4. The core histones are H2A, H2B, H3 and H4, whereas histones H1/H5 are identified as the linker histones. Moreover the dynamics of chromatin structure depend on posttranslational modification of histones in addition to the appearance of different histone variants. Histone H3 as well as H4 are modified covalently at several residues. The histone code is constitute by these and the H2A/H2B modifications.

Paraoxonase-1 or PON1 is part of the paraoxonase group of proteins. PON1 is an enzyme, responsible to the toxic metabolites of a different of organophosphorus insecticides hydrolyzation. Furthermore, PON1 is a dominant anti-atherosclerotic part of HDL. The enzyme needs PPAR-gamma for activation, leading to synthesis and release of paraoxonase 1 from the liver tissue, resulting in atherosclerosis reduction. PON1 has many qualities for atheroprotective through inflammatory lipid peroxides metabolism. This enzyme can hydrolyze a large number of substrates, for example cyclic carbonates, lactones, nerve gases etc.

Calpain, Small Subunit 1 (CAPNS1) belongs to the calpain small subunit family. Calpains are a ubiquitous, well-conserved family of calcium-dependent, cysteine proteases, widely distributed in mammalian cells. Calpain families are implicated in neurodegenerative processes, considering that their activation can be triggered by calcium influx and oxidative stress. Calpains function as heterodimers, comprising a specific large catalytic subunit (calpain 1 subunit in Calpain I, and calpain 2 subunit in Calpain II), and a common small regulatory subunit encoded by the CAPNS1 gene. The CAPNS1 protein is vital for the stability and function of both calpain heterodimers, whose proteolytic activities influence numerous cellular functions including apoptosis, proliferation, migration, adhesion, and autophagy.

Human immunodeficiency virus (HIV) is a retrovirusthat can lead to a condition in which the immune systembegins to fail, leading to opportunistic infections. HIV primarily infects vital cells in the humanimmune systemsuch as helper T cells(specifically CD4+ T cells), macrophagesand dendritic cells. HIV infection leads to low levels of CD4+ T cells through three main mechanisms: firstly, direct viral killing of infected cells; secondly, increased rates of apoptosisin infected cells; and thirdly, killing of infected CD4+ T cells by CD8 cytotoxic lymphocytesthat recognize infected cells. When CD4+ T cell numbers decline below a critical level, cell-mediated immunityis lost, and the body becomes progressively more susceptible to opportunistic infections. HIV was classified as a member of the genus Lentivirus, part of the family of Retroviridae. Lentiviruses have many common morphologies and biological properties. Many species are infected by lentiviruses, which are characteristically responsible for long-duration illnesses with a long incubation period. Lentiviruses are transmitted as single-stranded, positive-sense, enveloped RNA viruses. Upon entry of the target cell, the viral RNA genomeis converted to double-stranded DNAby a virally encoded reverse transcriptasethat is present in the virus particle. This viral DNA is then integrated into the cellular DNA by a virally encoded integraseso that the genome can be transcribed. Once the virus has infected the cell, two pathways are possible: either the virus becomes latentand the infected cell continues to function, or the virus becomes active and replicates, and a large number of virus particles are liberated that can then infect other cells.