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ME2 catalyzes the oxidative decarboxylation of malate to pyruvate, malat + NAD(P)+? pyruvate + CO2 + NAD(P)H+, and is found both in eukaryotic and prokaryotic cells. Three different isoforms of ME are known to be in mammalian tissues: a strictly cytosolic NADP+-dependent enzyme, an NADP+-dependent mitochondriail isoform, and a mitochondrial isoenzyme that is able to use both NAD+ and NADP+ but is more effective with NAD+. The mammalian isoforms size is about 62-64 kDa. A native size of 240,000 Da proposes a tetrameric structure for the active enzyme.
Mitochondrial NAD+-dependent ME 2 activity is seen in tissues that experience many cell divisions, like spleen, thymus, and the basal cells of the small intestinal mucosa. ME2 is also expressed all through the rapid cleavage stages of early Xenopus development. Activity for this isoform is low or nonexistent in brain, muscle, and normal and regenerating liver tissue from rat but was observed in rat adrenal cortex, pigeon and human skeletal muscle, and in heart muscle of some species. In addition, it is expressed in mitochondria of all tumor cells inspected to detain ascites tumors, hepatoma cells, and a variety of other tumors and transformed cell lines.

Dehydrogenase/reductase SDR family member 9 (DHRS9) functions as a homotetramer, which converts both 3-alpha-tetrahydroprogesterone (allopregnanolone) and 3-alpha-androstanediol to dihydroxyprogesterone and is believed to have a part in retinoic acid biosynthesis.

Myeloperoxidase is an important enzyme used by granulocytes during phagocytic lysis of foreign particles engulfed. In normal tissues and in a variety of myeloproliferative disorders myeloid cells of both neutrophilic and eosinophilic types, at all stages of maturation, exhibit strong cytoplasmic reactivity for MPO. Erythroid precursors, megakaryocytes, lymphoid cells, mast cells, and plasma cells are nonreactive. MPO is not observed in the neoplastic cells of a wide variety of epithelial tumors and sarcomas. MPO is useful in differentiating between myeloid and lymphoid leukemias.

Lipase Endothelial (LIPG) has extensive phospholipase activity and may be involved in lipoprotein metabolism and vascular biology. The LIPG protein is considered a member of the TG lipase family through its sequence and characteristic lid region which provides substrate specificity for enzymes of the TG lipase family. In addition, the LIPG has triglyceride lipase activities. LIPG hydrolyzes HDLs more efficiently than other lipoproteins. LIPG also binds heparin.

LPL is a lipoprotein lipase, which is expressed in the heart, muscle, and adipose tissue. LPL acts as a homodimer, and has the dual functions of triglyceride hydrolase and ligand/bridging factor for receptor-mediated lipoprotein uptake. Type I hyperlipoproteinemia is a result of severe mutations which cause LPL deficiency, whereas less extreme mutations in LPL are linked to many disorders of lipoprotein metabolism. Lipoprotein lipase (LPL) is a fundamental enzyme in plasma triglyceride hydrolysis and is secreted by macrophages in the subendothelial space. LPL also promotes the development of atherosclerosis through facilitation of monocyte adhesion to endothelial cells, stimulation of tumor necrosis factor alpha (TNF) secretion and induction of vascular smooth muscle cell proliferation.

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.

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.

Dehydrogenase/reductase SDR family member 4 (DHRS4) is a member of the short-chain dehydrogenases/reductases (SDR) family. DHRS4 reduces all trans retinal and 9-cis retinal. In addition, the DHRS4 protein can catalyze the oxidation of all trans retinol with NADP as cofactor, but with a much lower efficiency. Furthermore, DHRS4 reduces alkyl phenyl ketones and alpha dicarbonyl compounds with aromatic rings, such as pyrimidine 4 aldehyde, 3 benzoylpyridine, 4 benzoylpyridine, menadione and 4 hexanoylpyridine.

NEIL1 is a member of a class of DNA glycosylases homologous to the bacterial Fpg/Nei family. These glycosylases initiate the first step in base excision repair by cleaving bases damaged by reactive oxygen species and introducing a DNA strand break via the associated lyase reaction. NEIL1 participates in the DNA repair pathway by initiating base excision repair by removing damaged bases, primarily oxidized pyrimidines.

Glycogen phosphorylase (PYGL) converts from inactive phosphorylase B to active phosphorylase A by phosphorylation of serine residue 15. Activity of the PYGL enzyme is further regulated by numerous allosteric effectors and hormonal controls. The liver isozyme supplies the glycemic demands of the body in general whereas the brain and muscle isozymes supply just those tissues.

MCSFR which is also familiar as CSF1R, is part of the type3 subfamily of receptor tyrosine kinases. MCSFR is expressed mainly on cells of the monocyte and macrophage lineage, stem cells, and in the growing placenta. Most of the biological effects of this cytokine are mediated by MCSFR. MCSFR contains an extracellular ligand-binding domain, a single membrane-spanning segment, and an intracellular tyrosine kinase domain. Originally CSF1 and this receptor were implicated as vital for normal trophoblastic implantation as well as monocyte development. The role of CSF1/CSF1R in normal mammary gland development is actually very interesting since this connection has also been discovered in the biology of breast cancer with the results of abnormal expression of CSF1 and its receptor. Likewise, in Alzheimer's disease and after brain injuries an increased level of CSF1R was found in the microglia, which causes the microglia to become more active.

Tumor necrosis factor is a cytokine involved in systemic inflammation and is a member of a group of cytokines that all stimulate the acute phase reaction. TNF is mainly secreted by macrophages.
TNF causes apoptotic cell death, cellular proliferation, differentiation, inflammation, tumorigenesis and viral replication, TNF is also involved in lipid metabolism, and coagulation. TNF's primary role is in the regulation of immune cells.
Dysregulation and, in particular, overproduction of TNF have been implicated in a variety of human diseases- autoimmune diseases, and cancer.

Hematopoietic Prostaglandin D Synthase (HPGDS) belongs to the sigma class glutathione-S-transferase family. The HPGDS enzyme catalyzes the conversion of PGH2 to PGD2 and has a role in the production of prostanoids in the immune system and mast cells. The presence of the HPGDS enzyme can be utilized to identify the differentiation stage of human megakaryocytes. Furthermore, HPGDS is a prostaglandin involved in smooth muscle contraction/relaxation and an effective inhibitor of platelet aggregation, and the conjugation of glutathione with a extensive range of aryl halides and organic isothiocyanates. In addition, HPGDS displays low glutathione-peroxidase activity towards cumene hydroperoxide. HPGDS is expressed in a number of megakaryocytic cell lines but not in platelets. HPGDS is highly expressed in the adipose tissue, macrophages and placenta; however it is expressed at lower levels in the lung, heart, lymph nodes, appendix, bone marrow and fetal liver.

GSTT2 belongs to the glutathione s-transferase (GST) family of proteins. There are eight GST proteins families, named alpha, kappa, mu, omega, pi, sigma, theta and zeta. Each one of the GST families has several proteins with different functions throughout the cell. The theta type members GSTT1 and GSTT2 have a 55% aa sequence homology and hold a vital role in human carcinogenesis. The theta genes are structurally similar – each has five exons with identical exon/intron boundaries.

Cardiotrophin 1 (CT-1) is a 201 amino acid member of the interleukin-6 superfamily. It was identified by its ability to induce hypertrophic response in cardiac myocytes. CT-1 mRNA levels were found both in cardiac myocytes and in cardiac nonmyocytes. CT 1 was also detected in abundance in normal adult human lung and was expressed in both fetal and adult airway smooth muscle cells. CT 1 activates gp130 dependent signaling and stimulates the Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathway to transduce hypertrophic and cytoprotective signals in cardiac myocytes.
CT 1 has also a neurotrophic function. CTF1 deficiency causes increased motoneuron cell death in spinal cord and brainstem nuclei of mice during a period between embryonic day 14 and the first postnatal week. Moreover, CT-1 is a hepatocyte survival factor that efficiently reduces hepatocellular damage in animal models of acute liver injury. Cardiotrophin 1 expression is augmented after hypoxic stimulation and it can protect cardiac cells when added either prior to simulated ischaemia or at the time of reoxygenation following simulated ischaemia. Cardiotrophin 1 can induce expression of the protective heat shock proteins (hsps) in cardiac cells.
Cardiotrophin-1 increased ventricular expression of ANP, brain natriuretic peptide (BNP) and angiotensinogen mRNA.
Cardiophin 1 levels were significantly elevated in patients with heart failure, patients with dilatative cardiomyopathy, moderate/severe mitral regurgitation, stable and unstable angina and after acute myocardial infarction.

PGLS is an enzyme in the second step pentose phosphate pathway. 6-Phosphogluconolactonase is crucial for the synthesis of nucleotide sugars and NADPH, the key cause for decreasing power. PGLS transforms 6-phosphogluconolactone to 6-phosphogluconate.

Hepatocyte Growth Factor (HGF) is a multifunctional growth factor which regulates both cell growth and cell motility. It exerts a strong mitogenic effect on hepatocytes and primary epithelial cells. HGF synergizes with Interleukin-3and GM-CSFto stimulate colony formation of hematopoietic progenitor cells in vitro and may, therefore, also modulate hematopoiesis.

Prolactin is a pituitary hormone involved in the stimulation of milk production, salt and water regulation, growth, development and reproduction. The initial step in its action is the binding to a specific membrane receptor (prolactin receptor) which belongs to the superfamily of class 1 cytokine receptors. The function of the prolactin receptor is mediated, at least in part, by two families of signaling molecules: Janus kinases and signal transducers and activators of transcription. Prolactin (PRL) is a hormone involved in a variety of important functions including ion transport and osmoregulation, stimulation of milk, protein synthesis as well as the regulation of numerous reproductive functions. PRL exerts its influence on different cell types through a signal transduction pathway which begins with the binding of the hormone to a transmembrane PRL receptor. Immunoreactive PRL receptor, a member of the cytokine receptor family, varies in size (short and long forms) with tissue source and species, from ~40 kDa to 100 kDa. The PRL receptor consists of at least three separate domains: an extracellular region with 5 cysteines which contains the prolactin binding site, a single transmembrane domain and a cytoplasmic region, the length of which appears to influence ligand binding and regulate cellular function.

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), and VEGFR-3 (Flt-4). Their expression is almost exclusively restricted to endothelial cells, but VEGFR-1 can also be found on monocytes. All VEGF-receptors have seven immunoglobulin-like extracellular domains, a single transmembrane region and an intracellular split tyrosine kinase domain. VEGFR-2 has a lower affinity for VEGF than the Flt-1 receptor, but a higher signalling activity. Mitogenic activity in endothelial cells is mainly mediated by VEGFR-2 leading to their proliferation. Differential splicing of the flt-1 gene leads to the formation of a secreted, soluble variant of VEGFR-1 (sVEGFR-1). No naturally occurring, secreted forms of VEGFR-2 have so far been reported. The binding of VEGF165 to VEGFR-2 is dependent on heparin.

GlpK also known as glycerol kinase, is a member of the FGGY kinase family. GlpK catalyzes the transfer of a phosphate group from ATP to glycerol, thereby forming glycerol phosphate. Furthermore, this intermediate can then be converted to dihydroxyacetone phosphate (DHAP), which is utilized in either glycolysis or gluconeogenesis. The activity of GlpK is affected by numerous metabolites. The non-competitive allosteric inhibition by fructose 1,6-bisphosphate (FBP) triggers modifications in the quaternary structure of Glpk.

Fibroblast Growth Factor-5 (FGF5) belongs to the FGF family of mitogenic peptides. In vitro, rhFGF5 is a mitogen for Balb/3T3 fibroblasts and bovine heart endothelial cells. FGF5 is also a major muscle-derived survival factor for cultured spinal motoneurons. In vivo, FGF5 is assumed to play central roles in both embryology and neurobiology. Developmentally, FGF5 mRNA is originally found in the embryoblast followed by the lateral somatic mesoderm, where it may play a part in angiogenesis, as well as the myotomes cranial to the tail region, where it may delay terminal myoblast differentiation during cell migration.

Il-6 is a cytokine with a wide variety of biological functions: it plays an essential role in the final differentiation of b-cells into ig-secreting cells, it induces myeloma and plasmacytoma growth, it induces nerve cells differentiation, in hepatocytes it induces acute phase reactants.

Tryptophanase, also known as tnaA, catalyzes chemical reaction using 2 substrates which are L-tryptophan and H2O. tnaA protein's three products are indole, pyruvate, and NH3.