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Geminin is a 25 kDa nuclear protein, which inhibits DNA replication and is degraded during the mitotic phase of the cell cycle. Geminin controls replication by binding to the licensing factor Cdt1, and is involved in neural differentiation. In addition, Geminin directly interacts with Six3 and Hox homeodomain proteins during embryogenesis and inhibits their functions. Geminin can also promote DNA replication. Geminin has 2 roles in 2 different stages of the cell cycle: Geminin is a negative regulator of DNA replication during the “S phase” of the cell cycle. Inhibition of Geminin during the “S phase” (by RNAi) results in an additional round of replication of portions of the genome. During the “M phase” of the cell cycle (mitosis) Geminin stabilizes the replication factor Cdt1 promoting DNA replication during the next cell cycle. Moreover, inhibition of Geminin during mitosis (by RNAi) causes destabilization of Cdt1 protein and impairment of DNA replication during the next cell cycle. Geminin thus guarantees that only one round of replication occurs during each cell cycle. It was discovered that Geminin is overexpressed in a number of malignancies and cancer cell lines. This maintains the concept that Geminin has also a positive role in DNA replication and cell cycle progression. Geminin accumulates through S, G2 and M phases of the cell cycle but is absent during the G1 phase. During the metaphase/anaphase transition of mitosis Geminin levels decrease.

Nedd4 Family Interacting Protein 1 (NDFIP1) is a part of a small group of evolutionarily conserved proteins having 3 ransmembrane domains. NDFIP1 is a possible target for ubiquitination by the Nedd4 family of proteins. NDFIP, which is a member of a family of integral Golgi membrane proteins, also modulates EGFR signaling through multiple pathways.

ANXA5 is a member of the annexin family of calcium-dependent phospholipid binding proteins which are involved in membrane-related activity along exocytotic and endocytotic pathways. ANXA5 is a phospholipase A2 and protein kinase C inhibitory protein with calcium channel properties and takes part in cellular signal transduction, inflammation, growth and differentiation. ANXA5 is an anticoagulant protein that acts as an indirect inhibitor of the thromboplastin-specific complex, which is involved in the blood coagulation cascade. ANXA5 regulates coagulability in the blood stream by binding to phosphatidylserine and sulfatide. ANXA5 protects sinsuoidal endothelial cells from ischemia reperfusion damage. ANXA5 is necessary for normal CFTR chloride channel activity.

MX2 is a member of 2 protein families: the dynamin family and the large GTPases family. MX2 has a cytoplasmic and nuclear structure which is found in a granular pattern in the heterochromatin region under the nuclear envelope. The nuclear form has a NLS (nuclear localization signal) at the amino terminal end however it is missing in the cytoplasmic form as a result of the use of a different translation start codon. MX2 is upregulated by IFN-a, but unlike myxovirus resistance protein 1 has no antiviral activity.

LAIR1 is a glycoprotein (~32kDa) expressed on the surface of the majority of human peripheral blood mononuclear leukocytes including T cells, B cells, NK cells, macrophages and dendritic cells. LAIR-1 functions as an inhibitory receptor in NK cells, T cells and B cells. Inhibitory receptors control the immune response to prevent lysis of cells recognized as self. Lair1 consists of a leader sequence, extracellular domain, transmembrane domain, cytoplasmic region.
LAIR1 is a member of both the immunoglobulin superfamily and the leukocyte-associated inhibitory receptor family. LAIR1 maps to a region of 19q13.4 labeled the leukocyte receptor cluster, which contains at least 29 genes encoding leukocyte-expressed receptors of the immunoglobulin superfamily.

Nonspecific lipid transfer proteins (nsLTPs) are expressed throughout the plant tissues. They have a typical cysteine pattern forming disulfide bonds and are important allergens in fruits and tree nuts. Sensitization to nsLTP Cor a 8.0101 is more frequent among patients with hazelnut allergy in the Mediterranean area than the northern parts of Europe.

Mouse Complement 5a (C5a) is a glycoprotein which is a member of a family of structurally and functionally related proteins known as anaphylatoxins. C5a is a 77 a.a. peptide created by the C5a convertase proteolytic cleavage of C5 ? chain in the classical and alternative complement pathway (C4b2a3b, C3bBb3b). The mouse C5a has four ? helices and three intrachain disulfide bonds which form a triple loop structure. C5a functions through G-protein coupled receptor (GPCR) (C5aR/CD88). C5a is a effective chemoattractant and anaphylatoxin which functions on all classes of leukocytes and on many other cell types including endothelial, smooth muscle, kidney, liver, and neural cells. Mouse C5a also mediates IL-8 release from bronchial epithelial cells. Furthermore, it triggers an oxidative surge in macrophages and neutrophils, causing the release of histamine in basophils and mast cells. The C5a anaphylatoxin activity on hepatocytes results indirectly from interaction with nonparenchymal cell via prostanoid secretion.

Actin-related protein 2/3 complex subunit 2 (ARPC2), is a part of the Rho family of small GTPases and one of seven subunits of the human Arp2/3 protein complex. The Arp2/3 protein complex has been implicated in the control of actin polymerization in cells and has been conserved through evolution. Nevertheless, the exact role of the protein (the p34 subunit) has yet to be determined.

Carcinoembryonic Antigen-Related Cell Adhesion Molecule 1 (CEACAM1) belongs to the carcinoembryonic antigen (CEA) gene family which is a part of the immunoglobulin superfamily. CEACAM1 is a cell adhesion protein which mediates homophilic cell adhesion in a calcium-independent way. CEACAM1 is a surface glycoprotein expressed on various blood cells, epithelial cells, and vascular cells. CEACAM1 functions as coinhibitory receptor in immune response, and plays a role also as an activator during angiogenesis.

BAG1 binds to BCL2 and is also called BCL2-associated athanogene. BAG1 increases the anti-apoptotic effects of BCL2 and is characterizes as a link between growth factor receptors and anti-apoptotic mechanisms. BAG1 inhibits the chaperone activity of HSP70/HSC70 by promoting substrate release. BAG1 inhibits the pro-apoptotic function of PPP1R15A, and has anti-apoptotic activity. BAG1 enhances the anti-cell death function of BCL2 induced by various stimuli.

a-Synuclein (amino acids 1-140), an acidic neuronal protein of 140 amino acids, is extremely heat-resistant and is natively unfolded with an extended structure primarily composed of random coils. a-synuclein has been suggested to be implicated in the pathogenesis of Parkinson’s disease and related neurodegenerative disorders, and more recently, to be an important regulatory component of vesicular transport in neuronal cells. Moreover, recent studies have shown that a-synuclein has chaperone activity and that this activity is lost upon removing its C-terminal acidic tail (amino acids 96-140).

S100A9 is part of the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100A9 protein is localized in the cytoplasm and/or nucleus of a wide range of cells, and participates in the regulation of several cellular processes such as cell cycle progression and differentiation. S100 genes include no less than 13 proteins which are localized as a cluster on chromosome 1q21. S100A9 is involved in the inhibition of casein kinase and altered expression of this protein is associated with the disease cystic fibrosis.

PHD finger protein 13 (PHF13) is necessary for normal chromosome separation during mitosis and also for normal chromosome condensation during the early stages of mitosis. PHF13 modulates chromatin structure.

a-Synuclein (amino acids 1-140), an acidic neuronal protein of 140 amino acids, is extremely heat-resistant and is natively unfolded with an extended structure primarily composed of random coils. a-synuclein has been suggested to be implicated in the pathogenesis of Parkinson’s disease and related neurodegenerative disorders, and more recently, to be an important regulatory component of vesicular transport in neuronal cells. Moreover, recent studies have shown that a-synuclein has chaperone activity and that this activity is lost upon removing its C-terminal acidic tail (amino acids 96-140).

Tropic 1808 is a candidate chemotropic factor induced by nerve injury. Tpc1808 protein, similar to NGF, could promote the expression of NF-H in a time-dependent manner. Tpc1808 is the gene related to promotion of nerve growth, and both the Tpc1808 gene and the Tpc1808 recombinant protein up-regulate the expression of NF-H in PC12 cells.

Vps20-associated 1 homolog (VTA1) is a member of the VTA1 family. The VTA1 protein is involved in the endosomal multivesicular bodies (MVB) pathway. Furthermore, VTA1 is interacts with CHMP1B, CHMP2A, CHMP5, VPS4B, KIAA0174 (IST1) and possibly CHMP3. VTA1 is believed to be a cofactor of VPS4A/B, which catalyzes membrane-associated ESCRT-III assemblies. In addition, VTA1 is involved in the sorting and down-regulation of EGFR and also in HIV-1 budding.

Extracellular signal-regulated kinases (ERKs) or classical MAP kinases are widely expressed protein kinaseintracellular signalingmolecules which are involved in functions including the regulation of meiosis, mitosis, and postmitotic functions in differentiated cells. Many different stimuli, including growth factors, cytokines, virusinfection, ligands for heterotrimeric G protein-coupled receptors, transforming agents, and carcinogens, activate the ERK pathway.
The term, "extracellular signal-regulated kinases", is sometimes used as a synonym for mitogen-activated protein kinase(MAPK), but has more recently been adopted for a specific subset of the mammalianMAPK family. In the MAPK/ERK pathway, Rasactivates c-Raf, followed by MEKand then MAPK1/2 (below). Ras is typically activated by growth hormones through receptor tyrosine kinasesand GRB2/SOS, but may also receive other signals. ERKs are known to activate many transcription factors and some downstream protein kinases. Disruption of the ERK pathway is common in cancers, especially Ras, c-Raf and receptors such as HER2.
Mitogen-activated protein kinase 3 (MAPK3) is also known as "extracellular signal-regulated kinase 1" (ERK1). Transgenic gene knockoutmice lacking MAPK3 are viable and it is thought that MAPK1 can fulfill most MAPK3 functions in most cells. The main exception is in T cells. Mice lacking MAPK3 have reduced T cell development past the CD4+CD8+ stage.

CFD is an important component of the alternative pathway of complement activation. CFD cleaves and activates factor B when it binds C3b or a C3b-like protein such as C3 or CVF. CFD is a serine protease that exists as a mature protease, but it exhibits a highly restricted specificity and it appears to be substrate activated. CFD cleaves factor B bound to C3b leading to the release of the Ba fragment and leaving the Bb fragment bound to C3b. The C3b,Bb complex is called a C3 or C5 convertase because it converts these proteins to their active forms by cleaving off the small peptides C3a and C5a, respectively.

BLOC1S2 is a member of the BLOC1S2 family. Biogenesis of lysosome-related organelles complex 1 or BLOC-1 is a universally expressed multisubunit protein complex which is essential for regular biogenesis of specialized organelles of the endosomal-lysosomal system, like melanosomes and platelet dense granules. BLOC1S2 takes part in cell proliferation.

PFDN6 is a subunit of the heteromeric prefoldin complex that chaperones developing actin and alpha- and beta-tubulin chains until they are transferred to the cytosolic chaperonin containing TCP1 (CCT) complex. PFDN6 binds specifically to cytosolic chaperonin (c-CPN), transfers target proteins to it and bind to developing polypeptide chain to promote folding in a setting where there are many competing pathways for nonnative proteins.

PRDX3 is part of the peroxiredoxin family of antioxidant enzymes, that reduces hydrogen peroxide and alkyl hydroperoxides. PRDX3 is particularly located in the mitochondria and involved in the regulation of cellular redox status by serving as a primary line of defense against H2O2 produced during respiration. PRDX3 is a significant regulator of the abundance of mitochondrial H(2)O(2), which itself promotes apoptosis in cooperation with other mediators of apoptotic signaling. PRDX3 mitochondrial protein is significantly decreased in Alzheimer Disease and Down Syndrome.

Chemokine (C-X-C motif) ligand 11 (CXCL11) is a small cytokine belonging to the CXC chemokine family that is also called Interferon-inducible T-cell alpha chemoattractant (I-TAC) and Interferon-gamma-inducible protein 9 (IP-9). It is highly expressed in peripheral blood leukocytes, pancreas and liver, with moderate levels in thymus, spleen and lung and low expression levels were in small intestine, placenta and prostate. Gene expression of CXCL11 is strongly induced by IFN-g and IFN-b, and weakly induced by IFN-a. This chemokine elicits its effects on its target cells by interacting with the cell surface chemokine receptor CXCR3, with a higher affinity than do the other ligands for this receptor, CXCL9 and CXCL10. CXCL11 is chemotactic for activated T cells. Its gene is located on human chromosome 4 along with many other members of the CXC chemokine family.

STAM Binding Protein (STAMBP) is a zinc metalloprotease which specifically cleaves Lys-63-linked polyubiquitin chains, however it doesn’t cleave Lys-48-linked polyubiquitin chains. STAMBP has a role in signal transduction for cell growth and MYC induction mediated by IL-2 and GM-CSF. In addition, STAMBP potentiates BMP signaling by antagonizing the inhibitory action of SMAD6 and SMAD7. STAMBP also has a major role in regulation of cell surface receptor-mediated endocytosis and ubiquitin-dependent sorting of receptors to lysosomes. Endosomal localization of STAMBP is essential for efficient EGFR degradation but not for its internalization. STAMBP is also involved in the negative regulation of PI3K-AKT-mTOR and RAS-MAP signaling pathways.

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.