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HER-2/neu (erbB-2) encodes an 185-kDa orphan receptor tyrosine kinase that is constitutively active as a dimer and displays potent oncogenic activity when overexpressed. Herstatin, as the product of alternative HER-2 transcript, retains intron 8.
The herstatin mRNA is expressed in normal human fetal kidney and liver, but is at reduced levels relative to p185HER-2 mRNA in carcinoma cells that contain an amplified HER-2 gene. Herstatin appears to be an inhibitor of p185HER-2, because it disrupts dimers, reduces tyrosine phosphorylation of p185, and inhibits the anchorage-independent growth of transformed cells that overexpress HER-2.

MAP kinase-activated protein kinase 3 (MAPKAPK3) is involved in inflammatory Reaction by regulating tumor necrosis factor (TNF) and IL6 production post-transcriptionally. MAPKAPK3 phosphorylates AU-rich elements (AREs)-binding proteins, like TTP/ZFP36, leading to control of stability and translation of TNF and IL6 mRNAs. Phosphorylation of TTP/ZFP36 (a major post-transcriptional regulator of TNF), promotes its binding to 14-3-3 proteins and reduces its ARE mRNA affinity resulting in inhibition of dependent degradation of ARE-containing transcript. MAPKAPK3 is activated by growth inducers and stress stimulation of cells.

Endothelial cells express three different vascular endothelial growth factor (VEGF) receptors, belonging to the family of receptor tyrosine kinases (RTKs). They are named VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1), VEGFR-3 (Flt-4). Their expression is almost exclusively restricted to endothelial cells, but VEGFR-1 can also be found on monocytes, dendritic cells and on trophoblast cells. The flt-1 gene was first described in 1990. The receptor contains seven immunoglobulin-like extracellular domains, a single transmembrane region and an intracellular splited tyrosine kinase domain. Compared to VEGFR-2 the Flt-1 receptor has a higher affinity for VEGF but a weaker signaling activity. VEGFR-1 thus leads not to proliferation of endothelial cells, but mediates signals for differentiation. Interestingly a naturally occuring soluble variant of VEGFR-1 (sVEGFR-1) was found in HUVE supernatants in 1996, which is generated by alternative splicing of the flt-1 mRNA. The biological functions of sVEGFR-1 still are not clear, but it seems to be an endogenous regulator of angiogenesis, binding VEGF with the same affinity as the full-length receptor.

KIT, also known as KIT Proto-Oncogene Receptor Tyrosine, is a cytokine receptor which is expressed not only in hematopoietic stem cells but likewise in other cell types. KIT binds to receptor tyrosine kinase type III, which is a stem cell factor, also named a "rigid factor" or "c-kit ligand". Once this receptor binds to stem cell factor (SCF), it forms a dimer which activates intrinsic tyrosine kinase activity, which sequentially phosphorylates & activates signaling molecules which breed signals in cells. This receptor protects vascular smooth muscle cells from apoptosis in addition to restoring cardiac function after myocardial infarction.

Killer Cell lectin-Like Receptor Subfamily K, Member 1 (KLRK1) is an activating receptor which has recently generated considerable interest. The most fascinating of these, are a couple of closely related proteins known as MICA and MICB. These are cell-surface molecules distantly related to MHC class I proteins, and their genes have elements of heat shock promoters. Thus, MICA and MICB are expressed in the course of cell stress and are up-regulated in tumor cells and during viral infections. This receptor-ligand combination has a crucial role in the immune response to various pathologies.

Twinfilin (TWF1) is a ubiquitous actin-monomer-binding protein which is composed of two ADF-homology domains. Twinfilin forms a 1:1 complex with ADP-actin-monomers, prevents nucleotide exchange on actin monomers and blocks assembly of the monomer into filaments. TWF1 is composed of 2 ADF/cofilin-like (ADF-H) domains joined by a short linker region and followed by a C-terminal tail of approximately 20 residues. The 2 ADF-H domains are approximately 20% homologous to ADF/cofilin and to each other. TWF1 protein may be an actin monomer-binding protein, and its localization to cortical G-actin-rich structures might be regulated by the small GTPase RAC1.

Tyrosine 3-monooxygenase (Th), is a rate-limiting enzyme in catecholamine synthesis. Th utilizes tetrahydrobiopterin as well as molecular oxygen to convert tyrosine to DOPA. Th regulates dopamine (DA) neurotransmission at the biosynthesis and reuptake steps. Th takes a vital part in the physiology of adrenergic neurons. Furthermore, Th effects overexpression in lymphocytes on the differentiation as well as function of T helper cells.

Ectodysplasin A Receptor, also known as EDAR belongs to the tumor necrosis factor receptor family. EDAR is a receptor for the soluble ligand ectodysplasin A, and is capable of activating the nuclear factor-kappaB, JNK, as well as caspase-independent cell death pathways. EDAR is necessary for the development of hair, teeth, and other ectodermal derivatives. Furthermore, mutations in EDAR resulted in autosomal dominant and recessive forms of hypohidrotic ectodermal dysplasia.

Dynein light chain roadblock-type 2 (DYNLRB2) functions as one of several non-catalytic accessory components of the cytoplasmic dynein complex which are considered to be involved in linking dynein to cargos and to adapter proteins that regulate dynein function. Cytoplasmic dynein functions as a motor for the intracellular retrograde motility of vesicles and organelles along microtubules.

Dihydrofolate reductase (DHFR) is an enzyme that reduces dihydrofolic acid to tetrahydrofolic acid, with NADPH as electron donor that can be converted to the kinds of tetrahydrofolate cofactors applied in 1-carbon transfer chemistry. DHFR converts dihydrofolate into tetrahydrofolate, which is a methyl group shuttle required for the de novo synthesis of purines, thymidylic acid, and specific amino acids. Even though the functional DHFR gene is mapped to chromosome 5, numerous intronless processed pseudogenes or dihydrofolate reductase-like genes are identified on separate chromosomes.
DHFR deficiency is associated with megaloblastic anemia.
DHFR knockdown plays a role in the anticancer activity of 2-hydroxyoleic acid.
DHFR gene insertion/deletion polymorphism is linked to variation in serum and red blood cell folate concentrations in women.

Tachykinin-3 belongs to the substance P-related tachykinin family. Tachykinins are active peptides that stimulate neurons, induce behavioral responses, are effective vasodilators and secretagogues, and contract (directly or indirectly) many smooth muscles. TAC3 and its receptor are essential switches of regulator of human puberty, regulated by the brain through the release of the GnRH which starts a chain of processes which eventually lead to the production of sex hormones.
During pregnancy, the expression of TAC3 is restricted to the outer syncytiotrophoblast of the placenta, significant concentrations of TAC3 can be identified in plasma as early as week 9, and plasma concentrations of TAC3 are grossly elevated in pregnancy-induced hypertension and pre-eclampsia. Higher Tachykinin-3 concentrations in normotensive pregnant women may be caused by the advanced gestational age and/or the result of a negative interaction of other vasoactive substances. TAC3 has a role in the continuance of high placental blood flow in normal pregnancy.

Mitogen-Activated Protein Kinase 6 (MAP2K6) is a part of the dual specificity protein kinase family. MAP2K6 phosphorylates and activates p38 MAP kinase in response to inflammatory cytokines or environmental stress. MAP2K6 is a vital component of the MAP kinase signal transduction pathway. MAP2K6 takes part in various cellular processes such as stress induced cell cycle arrest and apoptosis.

Dynein light chain roadblock-type (DYNLRB1) belongs to the roadblock dynein light chain family and encodes a cytoplasmic protein which is capable of binding intermediate chain proteins. Upregulation of the DYNLRB1 gene is linked with hepatocellular carcinomas, suggesting that DYNLRB1 may be involved in tumor progression.

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.

DDIT3 reduces DNA-binding activity of C/EBP and lap by forming heterodimers which don’t bind DNA. DDIT3, also known as GADD153, is a basic domain-leucine zipper(bZIP) transcription factor of C/EBP family. DDIT3 protein is up-regulated by several stresses, such as amino acid or glucose starvation, endoplasmic reticulum (ER) stress, osmotic stress and hypoxia. DDIT3 protein is invloved in ER stress-mediated apoptosis and in disease including diabetes, brain ischemia and neurodegenerative disease. DDIT3 plays a role in asoprisnil-induced apoptosis. Hypoglycaemia-induced necrotic cell death of neuroblastoma cells is an active process mediated via the induction of the transcription factor DDIT3. DDIT3 plays an important role in melanoma progression. HRG stimulation of mammary epithelial cells induces the expression of DDIT3 mRNA and protein and transcription of DDIT3 promoter.

Tachykinin-1 (TAC1) belongs to the tachykinin peptide hormone family. TAC1 are a family of peptides which have similar biologic activities and share a common C-terminal sequence, phe-X-gly-leu-met-NH2, however they have distinct N-terminal sequences that convey receptor specificities. TAC1 is assumed to act as neurotransmitters which interact with nerve receptors and smooth muscle cells. TAC1 induces behavioral responses and serves as vasodilators and secretagogues.

Truncated BH3 interacting domain death agonist is a truncated form of the pro-apoptotic full-length BID. Truncated BH3 interacting domain death agonist is generated by Caspase-8 cleavage of BID. The truncated form of the protein translocates from the cytosol to mitochondria and transduces apoptotic signals.
BID is a pro-apoptotic Bcl-2 protein having only the BH3 domain. In reaction to apoptotic signaling, BID interacts with another Bcl-2 family of cell death regulators, called Bax, they form a heterodimer resulting to the insertion of Bax into the outer mitochondrial membrane. Bax induces the opening of the mitochondrial voltage-dependent anion channel which lead to the release of cytochrome c and other pro-apoptotic factors from the mitochondria resulting in activation of caspases. BID is a mediator of mitochondrial damage induced by caspase-8 (CASP8). CASP8 cleaves BID, and the COOH-terminal part translocates to mitochondria where it triggers cytochrome c release. The major proteolytic product p15 BID releasea cytochrome c. Isoform 1, Isoform 2 and Isoform 4 induce ice-like proteases and apoptosis while Isoform 3 does not induce apoptosis.

Gankyrin (proteasome 26S subunit) is a multicatalytic proteinase oncoprotein commonly overexpressed in most hepatocellular carcinomas. Proteasomes are found throughout eukaryotic cells at a high concentrations and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway. Gankyrin interacts with S6 ATPase of the 19S regulatory particle of the 26S proteasome. Gankyrin is involved in theregulation of the phosphorylation of the retinoblastoma protein by CDK4, and to enhance the ubiquitinylation of p53 by MDM2. Gankyrin consists of 7 ankyrin repeats and is structurally similar to I kappa Bs. Gankyrin acts as a regulatory subunit of the 26s proteasome which is involved in the atp-dependent degradation of ubiquitinated proteins. Gankyrin is involved in progression of esophageal squamous cell carcinoma. gankyrin plays an oncogenic role especially in early stages of human epatocarcinogenesis. Gankyrin binds to NF-kappaB and suppresses its activity at the transcription level by modulating acetylation through SIRT1. Structural comparison between Gankyrin & p16(INK4A) identified numerous residues of gankyrin that are potentially important for CDK4 binding.

Sepiapterin Reductase is an aldo-keto reductase that catalyzes the NADPH-dependent reduction of pteridine derivatives and is essential in the biosynthesis of BH4. Mutations in Sepiapterin Reductase gene result in DOPA-responsive dystonia due to sepiaterin reductase deficiency defined by the presence of sustained involuntary muscle contractions, often leading to abnormal postures. Sepiapterin reductase is part of the short-chain dehydrogenase/reductase family which reduces exogenous carbonyl compounds as well as phenylpropanedione. Sepiapterin reductase is an important enzyme for the biosynthesis of tetrahydrobiopterin, an necessary cofactor for aromatic amino acid hydrolases together with tyrosine hydroxylase, the rate-limiting enzyme in DOPA synthesis.

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.

TIE-1 (tyrosine kinase with Ig and EGF homology domains 1) and TIE-2/Tek comprise a receptor tyrosine kinase (RTK) subfamily with unique structural characteristics: two immunoglobulin-like domains flanking three epidermal growth factor (EGF)-like domains and followed by three fibronectin type III-like repeats in the extracellular region and a split tyrosine kinase domain in the cytoplasmic region. These receptors are expressed primarily on endothelial and hematopoietic progenitor cells and play critical roles in angiogenesis, vasculogenesis and hematopoiesis. Human TIE-1 cDNA encodes a 1122 amino acid (aa) residue precursor protein with an 18 residue putative signal peptide, a 726 residue extracellular domain and a 353 residue cytoplasmic domain. Two ligands, angiopoietin-1 (Ang1) and angiopoietin-2 (Ang2), which bind TIE-2 with high-affinity have been identified. Ang2 has been reported to act as an antagonist for Ang1. Mice engineered to overexpress Ang2 or to lack Ang1 or Tie-1 display similar angiogenic defects.

TRXR is a ubiquitous enzyme which participates in various cellular processes such as cell growth, p53 activity, and protection against oxidation stress. The mammalian Thioredoxin reductase cleaves thioredoxins as well as non-disulfide substrates such as selenite, lipoic acids, lipid hydroperoxides, and hydrogen peroxidec.

Dihydrofolate reductase (DHFR) is an enzyme that reduces dihydrofolic acid to tetrahydrofolic acid, with NADPH as electron donor that can be converted to the kinds of tetrahydrofolate cofactors applied in 1-carbon transfer chemistry. DHFR converts dihydrofolate into tetrahydrofolate, which is a methyl group shuttle required for the de novo synthesis of purines, thymidylic acid, and specific amino acids. Even though the functional DHFR gene is mapped to chromosome 5, numerous intronless processed pseudogenes or dihydrofolate reductase-like genes are identified on separate chromosomes. DHFR deficiency is associated with megaloblastic anemia. DHFR knockdown plays a role in the anticancer activity of 2-hydroxyoleic acid. DHFR gene insertion/deletion polymorphism is linked to variation in serum and red blood cell folate concentrations in women.