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Actin is one of the most highly-conserved proteins, differing by no more than 20% in species as diverse as algae and humans .Actin or ACTA is aprotein localized in the I band of the myofibrils in the muscle, Acting together with myosin.Actin takes part in the contraction and relaxation of muscle. Actin exists as a monomer in low salt concentrations, but filaments form rapidly as salt concentration rises, with the consequent hydrolysis of ATP.Each actin protomer binds one molecule of ATP and has one high affinity site for either calcium or magnesium ions, as well as several low affinity sites. It occurs in globular (G-actin) and fibrous (F-actin) forms. Actin is found in all eukaryotic cells (except for nematode sperm). Its other activitiessuch as cell motility, cell division and cytokinesis, vesicle and organelle movement, cell signaling, and the establishment and maintenance of cell junctions and cell shape.

SKP1 is a F-box enzyme which functions as a substrate recognition component of the SCF ubiquitin ligase complex which controls the ubiquitination of proteins involved in cell cycle progression, signal transduction and transcription. SKP1 binds to proteins containing an F-box motif, such as cyclin F, S-phase kinase-associated protein 2, and other regulatory proteins involved in ubiquitin dependent proteolysis. SKP1 takes part in the control of beta-catenin levels and the activity of beta-catenin dependent TCF transcription factors. SKP1 serves as an adapter that links the F-box protein to CUL1 in the SCF complex.

Dynein Axonemal Light Intermediate Chain1 also known as DNALI1 belongs to the inner dynein arm light chain family. DNALI1 take a dynamic role in flagellar motility. DNALI1 is the human homolog of the Chlamydomonas inner dynein arm gene, p28. The exactfunction of DNALI1 is not known yet, on the other hand, it is a potential candidate for immotile cilia syndrome. In addition it has been found that the following diseases: primary ciliary dyskinesia, and huntington's disease have been associated with DNALI1. Ultrastructural defects of the inner dynein arms are seen in patients with ICS. Immotile mutant strains ofChlamydomonas, biflagellated algae, show similar defects.

SIL1 is localized to endoplasmic reticulum (ER). SIL1 is an N-linked glycoprotein with an N-terminal ER targeting sequence, 2 putative N-glycosylation sites, and a C-terminal ER retention signal. SIL1 acts as a nucleotide exchange factor for another unfolded protein response protein. Mutations in SIL1 are linked to Marinesco-Sjogren syndrome.

Myelin Protein Zero-Like 1 (MPZL1) is a cell surface receptor, which is involved in signal transduction processes. MPZL1 recruits PTPN11/SHP-2 to the cell membrane and is a putative substrate of PTPN11/SHP-2. MPZL1 is a main receptor for concanavalin-A (ConA) and it is involved in cellular signaling induced by ConA, which most likely includes Src family tyrosine-protein kinases. MPZL1 Isoform 3 appears to have a dominant negative role by blocking tyrosine phosphorylation of MPZL1 induced by ConA. Isoform 1, but not isoform 2 and isoform 3, might be involved in regulation of integrin-mediated cell motility.

RAB3A Interacting Protein Like 1 (RAB3IL1) is a 382 amino acid protein which is a member of the SEC2 family. RAB3IL1 is a guanine nucleotide exchange factor (GEF) for Rab3A. RAB3IL1 competes for interaction with Rab3A and IHPK1 via its coiled coil domain, which doesn’t involve IHPK1 kinase activity.

ACAA1 is part of the thiolase family of enzymes and is takes part in lipid metabolism. ACAA1 enzyme is localized to the peroxisome and catalyzes the conversion of acyl-CoA and acetyl-CoA to 3-oxoacyl-CoA in the fatty acid oxidation pathway. ACAA1 shows high enzymatic activity in liver, kidney, intestine and white adipose tissue in rats. ACAA1 deficiency causes pseudo-Zellweger syndrome.

MCM7 is a highly conserved mini-chromosome maintenance protein (MCM) vital for eukaryotic genome replication initiation. The MCM proteins form a hexameric protein complex which is a key component of the pre-replication complex (pre_RC) which takes part in replication forks formation and in DNA replication related proteins recruitment. The MCM complex is comprised of MCM2, 4, 6 and 7 proteins and possesses DNA helicase activity, such as DNA unwinding.

ENO3 is one of three enolase isoenzymes in mammals. The homodimer ENO3 is located in skeletal muscle cells of adults and has a part in converting phosphoglyceric acid to phosphenolpyruvic acid in the glycolytic pathway. Mutations in ENO3 gene is linked to metabolic myopathies which is caused by low stability of the enzyme.

SDF-1 (stromal cell-derived factor-1) is small cytokine belonging to the chemokine family that is officially designated Chemokine (C-X-C motif) ligand 12 (CXCL12). It is produced in two forms, SDF-1?/CXCL12a and SDF-1?/CXCL12b, by alternate splicing of the same gene. Chemokines are characterized by the presence of four conserved cysteines, which form two disulfide bonds. The CXCL12 proteins belong to the group of CXC chemokines, whose initial pair of cysteines are separated by one intervening amino acid. CXCL12 is strongly chemotactic for lymphocytes and has been implicated as an important cell co-ordinator during development. During embryogenesis it directs the migration of hematopoietic cells from foetal liver to bone marrow. Mice which were knocked-out for CXCL12 gene were lethal before the birth or within just 1 hour of life. As another role, CXCL12a alters also the electrophysiology of neurons. CXCL12 was shown to be expressend in many tissues in mice (including brain, thymus, heart, lung, liver, kidney, spleen and bone marrow).
The receptor for this chemokine is CXCR4, which was previously called fusin. This CXCL12-CXCR4 interaction used to be considered exclusive (unlike for other chemokines and their receptors), but recently it was suggested that CXCL12 is also bound by CXCR7 receptor.
The gene for CXCL12 is located on human chromosome 10. In human and mouse both CXCL12 and CXCR4 show high identity of sequence: 99% and 90%, respectively.

Tetratricopeptide repeat protein 1 (TTC1) is comprised of 292 amino acids with 3 TPR motifs, such as a Galpha16-binding protein. This interaction is confirmed both in vitro and in transfected mammalian cells, where TTC1 also binds to a number of other Galpha proteins. TTC1 interacts with Ha-Ras especially in its active form. TTC1 also interacts with the GAP domain of NF1.

Chemokine (C-C motif) ligand 21 (CCL21) is a small cytokine belonging to the CC chemokine family. This chemokine is also known as 6Ckine (because it has six conserved cysteine residues instead of the four cysteines typical to chemokines), exodus-2, and secondary lymphoid-tissue chemokine (SLC). CCL21 is expressed predominantly in the lymph nodes and, in contrast to other CC chemokines, is chemotactic for lymphocytes. The gene for CCL21 is located on human chromosome 9. CCL21 elicits its effects by binding to a cell surface chemokine receptor known as CCR7.

SDF-1 (stromal cell-derived factor-1) is small cytokine belonging to the chemokine family that is officially designated Chemokine (C-X-C motif) ligand 12 (CXCL12). It is produced in two forms, SDF-1?/CXCL12a and SDF-1?/CXCL12b, by alternate splicing of the same gene. Chemokines are characterized by the presence of four conserved cysteines, which form two disulfide bonds. The CXCL12 proteins belong to the group of CXC chemokines, whose initial pair of cysteines are separated by one intervening amino acid. CXCL12 is strongly chemotactic for lymphocytes and has been implicated as an important cell co-ordinator during development. During embryogenesis it directs the migration of hematopoietic cells from foetal liver to bone marrow. Mice which were knocked-out for CXCL12 gene were lethal before the birth or within just 1 hour of life. As another role, CXCL12a alters also the electrophysiology of neurons. CXCL12 was shown to be expressend in many tissues in mice (including brain, thymus, heart, lung, liver, kidney, spleen and bone marrow).
The receptor for this chemokine is CXCR4, which was previously called fusin. This CXCL12-CXCR4 interaction used to be considered exclusive (unlike for other chemokines and their receptors), but recently it was suggested that CXCL12 is also bound by CXCR7 receptor.
The gene for CXCL12 is located on human chromosome 10. In human and mouse both CXCL12 and CXCR4 show high identity of sequence: 99% and 90%, respectively.

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.

Acetoacetyl-CoA thiolase (ACAT1) is an enzyme member of the membrane-bound acyltransferase family and Sterol o-acyltransferase subfamily. The ACAT1 enzyme catalyzes the reversible formation of acetoacetyl-CoA from 2 molecules of acetyl-CoA. ACAT1 plays a part in lipoprotein compilation and dietary cholesterol absorption. Added to its acyltransferase activity, ACAT1 acts as a ligase.

Profilin-1 also known as Pfn1 is a ubiquitous actin monomer-binding protein which is a member of the profilin family. Pfn1 significantly enhances skin wound healing in-vitro as well as in-vivo which is mediated by purinergic receptors. Furthermore, Pfn1 is also active in endothelial cell migration and vessel sprouting. Pfn1 is considered to regulate actin polymerization in response to extracellular signals.

Snail homolog 1 (SNAI1) is involved in induction of the epithelial to mesenchymal transition (EMT), formation and maintenance of embryonic mesoderm, growth arrest, survival and cell migration. SNAI1 binds to 3 E-boxes of the E-cadherin gene promoter and represses its transcription. The nuclear protein encoded by SNAI1 is structurally identical to the Drosophila snail protein, and is considered as well to be vital for mesoderm formation in the developing embryo. At least two variants of a similar processed pseudogene have been found on chromosome 2. Among the diseases associated with SNAI1 are waardenburg syndrome type iid, and inappropriate adh syndrome.

Neuron-specificenolase also caled NSE is a glycolytic isoenzyme which is situated in central and peripheral neurons and neuroendocrine cells. Enolase-2 is released into the CSF when neural tissue is injured. Neoplasms derived from neural or neuroendocrine tissue release Enolase-2 into the blood. Enolase-2 is a useful substance that has been detected in patients with certain tumors, such as neuroblastoma, small cell lung cancer, medullary thyroid cancer, carcinoid tumors, pancreatic endocrine tumors, and melanoma. ENO2 is 1 of the 3 enolase isoenzymes found in mammals. ENO2 isoenzyme, is found in mature neurons and cells of neuronal origin. An exchange from alpha enolase to gamma enolase occurs in neural tissue during development in rats and primates.

SAA1 protein is an acute phase apolipoprotein reactant which is produced mostly by hepatocytes and under regulation of inflammatory cytokines. SAA1 (Serum amyloid A1) protein is produced mainly in the liver and circulates in low levels in the blood. The SAA1 seems to have a role in the immune system. SAA1 protein levels increase in the blood and other tissues under conditions of inflammation. SAA1 may facilitate the repair of injured tissues; it also acts as an antibacterial agent, and signals the migration of germ-fighting cells to sites of infection. SAA1 also functions as an apolipoprotein of the HDL complex.
Elevated levels of SAA1 ultimately affect secondary amyloidosis, extracellular amassing of amyloid fibrils, resulting from a circulating precursor, in a variety of tissues and organs. The most widespread type of amyloidosis appears secondary to chronic inflammatory disease, mainly rheumatoid arthritis. The SAA1 cleavage product a designated amyloid protein A is deposited systemically as amyloid in vital organs such as the liver, spleen, and kidneys in chronic inflammatory diseases patients. These deposits are extremely insoluble and resistant to proteolysis; they disrupt tissue structure and compromise performance.

Acidic fibroblast growth factor is a member of the fibroblast growth factor (FGF) family. FGF family members possess broad mitogenic and cell survival activities, and are involved in a variety of biological processes, including embryonic development, cell growth, morphogenesis, tissue repair, tumor growth and invasion. This protein functions as a modifier of endothelial cell migration and proliferation, as well as an angiogenic factor. It acts as a mitogen for a variety of mesoderm- and neuroectoderm-derived cells in vitro, thus is thought to be involved in organogenesis.
Three alternatively spliced variants encoding different isoforms have been described.
The hep-binding growth factors are angiogenic agents in vivo and are potent mitogens for a variety of cell types in vitro. There are differences in the tissue distribution and concentration of these 2 growth factors.

THAP domain-containing protein 1 (THAP1) is a 213 amino acid protein which is restricted to the nucleoplasm and contains one THAPtype zinc finger, a conserved DNA-binding domain. THAP1 is a DNA-binding transcription regulator which regulates endothelial cell proliferation and G1/S cell-cycle progression. In addition, THAP1 has a pro-apoptopic activity by potentiating both serum-withdrawal and TNF-induced apoptosis. THAP1 protein colocalizes with the apoptosis response protein PAWR/PAR-4 in promyelocytic leukemia (PML) nuclear bodies, and serves as a proapoptotic factor which connects PAWR to PML nuclear bodies.

Connective Tissue Growth Factor belongs to the CCN family of proteins. The CCN family presently consists of six members in human also known as: Cyr61 (Cystein rich 61), CTGF (Connective Tissue Growth Factor), Nov (Nephroblastoma Overexpressed gene), WISP-1, 2 and 3 (Wnt-1 Induced Secreted Proteins). The CCN genes encode secreted proteins associated with the Extracellular Matrix (ECM) and cell membrane. CCN proteins are matricellular proteins which are involved in the regulation of various cellular functions including: proliferation, differentiation, survival, adhesion and migration. They are expressed in derivatives of the three embryonic sheets and are implicated in the development of kidney, nervous system, muscle, bone marrow, cartilage and bone. During adulthood, they are implicated in wound healing, bone fracture repair, and pathologies such as: fibrosis, vascular ailments and tumorigenesis.
Full length secreted CCN proteins can show an antiproliferative activity, whereas truncated isoforms are likely to stimulate proliferation and behave as oncogenes. The full length protein consists of four modulesModule I shares partial identity with the N-terminal part of the Insulin-like Growth Factor Binding Proteins (IGFBPs).
Module II includes a stretch of 70amino acid residues – which shares sequence identity with the Von Willebrand Factor Type C repeat (VWC).
Module III contains sequences sharing identity with the Thrombospondin type 1 repeat (TSP1) (WSXCSXXCG), which is thought to be implicated in the binding of sulfated glycoconjugates and to be important for cell adhesion. Module IV, also designated CT, is encoded by exon5. It is the leasts conserved one of the four domains at the level of nucleotide sequence, but it appears to be critical for several of the biological functions attributed to the CCN proteins. Module IV resembles the CT domain of several extracellular protein including, Von Willebrand's factor and mucins. Sequence similarities to heparin-binding motifs are also found within this domain. Proteolysis of the secreted full-length CCN proteins that has been reported in the case of CCN2 and CCN3 might result in the production of CCN-derived peptides with high affinity for ligands that full-length CNN proteins bind only poorly. Amino-truncated CCN2 isoforms were biologically active whereas no specific biological activity has been attributed to the truncated CCN3. Although the molecular processes underlying the production of these secreted isoforms is presently unknown, it is important to note that proteolysis occur at the same amino acid residues in both CCN2 and CCN3. An elevated expression of CCN2 has also been detected by Northern blotting in human invasive mammary ductal carcinomas, dermatofibromas, pyogenic granuloma, endothelial cells of angiolipomas and angioleiomyomas, and in pancreatic tumors. A study performed with chondrosarcomas representative of various histological grades established that CCN2 expression was closely correlated with increasing levels of malignancy. In agreement with CCN2 playing a role in brain tumor angiogenesis, immunocytochemistry studies indicated that both glioblastoma tumor cells and proliferating endothelial cells stained positive for CCN2. In astrocytomas, CCN2 expression was particularly elevated in high grade tumors, with a marked effect of CCN2 on cell proliferation. Downregulation of CCN2 expression in these cells was associated with a growth arrest at the G1/S transition while over-expression of CCN2 induced a two-fold increase of the number of cells in the G1 phase. Gene profiling analysis allowed to identify a set of about 50 genes whose expression might account for the proliferative activity of CCN2 in these cells.
CCN2 was seen in a higher proportion of mononuclear cells of patients with acute lymphoblastic leukemia.