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RASSF1A is a protein similar to the RAS effector proteins. Loss or altered expression of the RASSF1A gene has been linked to the pathogenesis of a variety of cancers, which suggests the tumor suppressor function of the RASSF1A gene. The inactivation of the RASSF1A gene was found to be interconnected with the hypermethylation of its CpG-island promoter region. The RASSF1A protein was found to interact with DNA repair protein XPA. RASSF1A was also shown to inhibit the accumulation of cyclin D1, and thus induce cell cycle arrest.

Vimentin expression in human malignant glioma cells depends on cellular density, algorithms of drug delivery and chemo/radio treatment. Vimentin and detyrosinated microtubules provide structural support for the extensive microtentacles observed in detached tumor cells and a mechanism to promote successful metastatic spread. Primary colorectal carcinomas display aberrant expression of vimentin, and have activated Notch and TGFbeta signaling pathways. Vimentin is a strong arterial substrate for transglutaminases. Transglutaminase-mediated vimentin dimerization results in a novel unifying pathway by which vasodilatory and remodeling responses may be regulated. Ablation of vimentin expression inhibits migration and invasion of colon and breast cancer cell lines. Vimentin is the main intermediate filament protein in mesenchymal cells and is therefore of value in the differential diagnosis of undifferentiated neoplasms.

Clathrin, light chain A (CLTA) is a member of the clathrin family. Clathrin, which is a large, soluble protein, is comprised of heavy and light chains. CLTA is one of 2 clathrin light chain proteins which are supposed to function as regulatory elements. CLTA is a key cytosolic coat protein in pits and vesicles originating from the plasma membrane and the trans-Golgi network. In receptor-mediated endocytosis, receptor proteins are encapsulated by Clathrin-coated vesicles.

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 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 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.

Chondrolectin (CHODL) is a type I membrane protein with a carbohydrate recognition domain characteristic of C-type lectins in its extracellular portion. In other proteins, this domain is involved in endocytosis of glycoproteins and exogenous sugar-bearing pathogens. The CHODL protein localizes mainly to the perinuclear region.

Acyl-CoA synthetase family member 2, also known as ACSF2 is a member of the ATP-dependent AMP-binding enzyme family. Acyl-CoA synthetases are a family of enzymes which catalyze the thioesterification of fatty acids with coenzymeA to form activated intermediates, which play a basic part in lipid metabolism as well as homeostasis of lipid-related processes. ACSF2 is required for the complex of lipid synthesis, energy production via beta-oxidation, protein acylation and fatty-acid dependent transcriptional regulation. Moreover, ACSF2 is required for fatty acid import into cells by the process of vectorial acylation.

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).

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.

Calbindins are Ca-binding proteins belonging to the troponin C superfamily. CALB28K/Calbindin1/CALB1 (D28K/Spot35 protein or cholecalcin, rat 261 aa; mouse 261 aa; human 261-aa, chromosome 8q21.3-q22.1) was originally described as 27-kDA induced by vitamin D in the duodenum of chicken. In mammals, it is expressed in the kidney, pancreatic islets, and brain. In brain, its synthesis is independent of vitamin D. CABP28K contains 4 active and 2 inactive EF-hand Ca-binding domains. The gene for CABP28K is clustered in the same region as carbonic anhydrase. The neurons in the brains of patients with Huntington disease are CAB28K depleted. There are two types of CaBPs: the "trigger"- and the "buffer"-CaBPs. The conformation of "trigger" type CaBPs changes upon Ca2+ binding and exposes regions on protein that interact with target molecules, thus altering their activity. The buffer-type CABP are thought to control the intracellular calcium concentration. Calbindin D-28K is found predominantly in subpopulations of central and peripheral nervous system neurons, and in certain epithelial cells involved in Ca2+ transport such as distal tubular cells and cortical collecting tubules of the kidney, and in enteric neuroendocrine cells.

PLAUR is one of 2 activators which convert the extracellular zymogen plasminogen to plasmin, a serine protease involved in a various normal and pathological processes that require cell migration and/or tissue destruction. PLAUR protein is synthesized and released from cells as a single-chain proenzyme with narrow enzymatic activity and is converted to an active two-chain disulfide-linked active enzyme by plasmin and other specific proteinases.

LRPAP1 is a member of the alpha-2-MRAP family. LRPAP1 cooperates with LRP1/alpha-2-macroglobulin receptor and glycoprotein 330. LRPAP1, located on the cell surface, creates a complex with the alpha 2 macroglobulin receptor light and heavy chains and has part in the pathogenesis of membrane glomerular nephritis.

DNAJB11 is a member of the evolutionarily conserved DNAJ/HSP40 family of proteins, which regulate molecular chaperone activity by stimulating ATPase activity. DNAJB11 serves as a co-chaperone for HSPA5 and binds directly to both unfolded proteins which are substrates for ERAD and nascent unfolded peptide chains, but dissociates from the HSPA5-unfolded protein complex before folding is completed.

DCTN2 is a 50kDa subunit of dynactin, which is a macromolecular complex consisting of 10-11 subunits ranging in size from 22 to 150 kDa. Dynactin binds to both microtubules and cytoplasmic dynein. Dynactin is involved in a various cellular functions, including ER-to-Golgi transport, the centripetal movement of lysosomes and endosomes, spindle formation, chromosome movement, nuclear positioning, and axonogenesis. The DCTN2 subunit is present in 4-5 copies per dynactin molecule. DCTN2 is comprised of 3 short alpha-helical coiled-coil domains which mediate association with self or other dynactin subunits. DCTN2 interacts directly with the largest subunit (p150) of dynactin and is able to affix p150 in place. DCTN2 modulates cytoplasmic dynein binding to an organelle, and plays a part in prometaphase chromosome alignment and spindle organization during mitosis. DCTN2 is involved in anchoring microtubules to centrosomes. DCTN2 has a role in synapse formation during brain development.

CTK-19 is a member of the keratin family. The keratins are intermediate filament proteins responsible for the structural integrity of epithelial cells and are subdivided into cytokeratins and hair keratins. The type I cytokeratins consist of acidic proteins which are arranged in pairs of heterotypic keratin chains. Unlike its related family members, this smallest known acidic cytokeratin is not paired with a basic cytokeratin in epithelial cells. It is specifically expressed in the periderm, the transiently superficial layer that envelopes the developing epidermis. The type I cytokeratins are clustered in a region of chromosome 17q12-q21.

BRCC3 is a subunit of the BRCA1-BRCA2-containing complex (BRCC), which is an E3 ubiquitin ligase. BRCC3 is also thought to be involved in the cellular response to ionizing radiation and progression through the G2/M checkpoint.

MICA (MHC class I chain-related gene A) is a transmembrane glycoprotein that functions as a ligand for human NKG2D. A closely related protein, MICB, shares 85% amino acid identity with MICA. These proteins are distantly related to the MHC class I proteins. They possess three extracellular Ig-like domains, but they have no capacity to bind peptide or interact with ?2-microglobulin. The genes encoding these proteins are found within the Major Histocompatibility Complex on human chromosome 6. The MICA locus is highly polymorphic with more than 50 recognized human alleles. MICA is absent from most cells but is frequently expressed in epithelial tumors and can be induced by bacterial and viral infections. MICA is a ligand for human NKG2D, an activating receptor expressed on NK cells, NKT cells,gammadelta T cells, and CD8+beta T cells. Recognition of MICA by NKG2D results in the activation of cytolytic activity and/or cytokine production by these effector cells. MICA recognition is involved in tumor surveillance, viral infections, and autoimmune diseases.

Receptor-associated Protein (aka RAP) averts the GCM-mediated enhancement of axon growth- ApoE-containing lipoproteins which are known to bind to receptors of the LDLr superfamily. In the presence of RAP, GCM doesn’t increase the axon extension rate in relation to base medium. Furthermore, the addition of RAP to the base medium doesn’t change the rate of axon extension. This implies that the growth stimulatory effect of apoE-containing lipoproteins secreted by glial cells is mediated by the LDLr family receptors. RAP annuls the growth stimulatory effect of GCM.

Aurora Kinase B (AURKB) belongs to a family of mitotic serine/threonine kinases. AURKB connects with chromosomes for the period of prophase prior to relocalizing to the spindle at anaphase. AURKB localizes to microtubules near kinetochores, specifically to the specialized microtubules called K-fibers. AURKB controls chromosome segregation through the control of microtubule-kinetochore attachment and cytokinesis. AURKB is required for kinetochore localization of BUB1 and SGOL1. AURKB expression during the G2/M phase transition is firmly coordinated with histone H3 phosphorylation, while overexpression is seen in many kinds of cancers. AURKB phosphorylates ''Ser-10'' and ''Ser-28'' of histone H3 during mitosis. AURKB is a component of the CPC (chromosomal passenger complex), which is a complex that acts as a key regulator of mitosis. High level expression of AURKB is seen in the thymus, which is also expressed in the spleen, lung, testis, colon, placenta and fetal liver. AURKB is expressed during S and G2/M phase and expression is up-regulated in cancer cells during M phase.

ARL2 is a member of the ADP-ribosylation factor (ARF) family. ARL2 functions as a component of a secretory pathway which is involved in the Ca2-dependent release of acetylcholine. ARL2 has a role in the folding of tubule proteins, thus playing a significant role in microtubule dynamics and cell cycle progression. Unlike other members of the ARF family, ARL2 doesn’t act as an activator of the catalytic subunit of cholera toxin.

PHD finger protein 11 (PHF11) is a regulator of TH1-type cytokine gene expression. The decline in PHF11 expression observed with an AD-associated genotype may promote the intense TH2 reactions which characterize numerous allergic individuals. PHF11 is linked with raised total serum IgE levels, asthma and acute atopic dermatitis (AD) in children. Even though PHF11 includes a plant homeodomain, a motif frequently found in transcriptional regulators, PHF11 function of has yet been examined.

BTLA, also known as B & T Lymphocyte Associated, is an inhibitory molecule which is part of the Ig superfamily. BTLA is a type 1 transmembrane glycoprotein in the CD28 family of T cell costimulatory molecules. BTLA is a 3rd inhibitory receptor on T lymphocytes with resemblances to CTLA-4 & PD-1. Moreover, BTLA is a ligand for TNF (receptor) superfamily, TNFRSF14, and HVEM. BTLA-HVEM complexes negatively regulate T-cell immune responses.

Treponema pallidum is a gram-negative spirochaete bacterium and is considered to be metabolically crippled. There are at least four known subspecies: T. pallidum pallidum, T. pallidum pertenue, T. pallidum carateum and T. pallidum endemicum. The helical structure of T. pallidum pallidum allows it to move in a corkscrew motion through viscous mediums such as mucus. Treponema pallidum subsp. pallidum has one of the smallest bacterial genomes at 1.14 million base pairs (Mb) and has limited metabolic capabilities, reflecting its adaptation through genome reduction to the rich environment of mammalian tissue.

NDK (Nucleoside diphosphate kinase) exists as a hexamer composed of 'A' (encoded by NME1) and 'B' (encoded by NME2) isoforms. NME1 is involved in cell proliferation, differentiation and development, signal transduction, G protein-coupled receptor endocytosis, and gene expression. It also has tumor metastasis-suppressive capacity. NME1 has a key role in the synthesis of nucleoside triphosphates other than ATP. NME1 is essential for neural development including neural patterning and cell future determination.
The NME1 gene is expressed in various tumor types where its levels have been alternatively linked to reduced or increased metastatic potential.
Decrease in NME1 expression is notably connected to aggressive behavior in melanoma, breast, colon, and gastric carcinomas. In contrast, elevated levels of NME1 gene expression are noted in the advanced stage of thyroid carcinomas.
Somatic mutations of the NME1 gene are found in neuroblastoma. Increased NME1 in neuroblastoma is linked to features of the disease that are associated with aggressive tumors.

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).