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Dickkopf-related protein 3 (DKK3) belongs to the DKK protein family including Dkk-1, 2, 3 and -4. DKK3 is a 350 amino acid secreted glycoprotein which is comprised of an N-terminal signal peptide and 2 conserved cysteine-rich domains that are separated by a 12 amino acid linker region. DKK3 is involved in embryonic development through its inhibition of the WNT signaling pathway. DKK3 gene expression is decreased in a variety of cancer cell lines and it may act as a tumor suppressor gene.

GMCSF is a cytokine that controls the production, differentiation, and function of granulocytes and macrophages. The active form of GMCSF is found extracellularly as a homodimer. GMCSF has been localized to a cluster of related genes at chromosome region 5q31, which is known to be associated with interstitial deletions in the 5q- syndrome and acute myelogenous leukemia. Other genes in the cluster include those encoding interleukins 4, 5, and 13.
GM-CSF stimulates the growth and differentiation of hematopoietic precursor cells from various lineages, including granulocytes, macrophages, eosinophils and erythrocytes.

Hepatitis B is one of a few known non-retroviralviruses which employ reverse transcriptionas a part of its replication process. (HIV, a completely unrelated virus, also uses reverse transcription, but it is a retrovirus.) HBV invades the cell by binding to surface receptor and become internalized. The viral core particles then migrate to the hepatocyte nucleus and the partially double-stranded, relaxed circular genomes (RC-DNA) are repaired to form a covalently closed circular DNA (cccDNA), which is the template for viral genomic and sub-genomic RNAs by cellular RNA polymerase II. Of these, the pregenomic RNA(pgRNA is selectively packaged into progeny capsids and is then reverse-transcribed into new RC-DNA. The core can either bud into the endoplasmic reticulum to be enveloped or exported from the cell or recycled back into the genome for conversion to cccDNA.

The cytokine Macrophage migration inhibitory factor (MIF) has been identified to be secreted by the pituitary gland and the monocyte/macrophage and to play an important role in endotoxic shock. MIF has the unique property of being released from macrophages and T cells in response to physiological concentrations of glucocorticoids. The secretion of MIF is tightly regulated and decreases at high, anti-inflammatory steroid concentration.

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.

The FGFs are a family of more than 20 small (~17–26 kDa) secreted peptides. The initial characterization of these proteins focused on their ability to stimulate fibroblast proliferation. This mitogenic activity was mediated through FGF receptors (FGFRs) 1, 2, or 3. A fourth closely related tyrosine kinase receptor (FGFR4) was able to bind the FGFs but did not lead to a mitogenic response.
FGFs modulate cellular activity via at least 5 distinct subfamilies of high-affinity FGF receptors (FGFRs): FGFR-1, -2, -3, and -4, all with intrinsic tyrosine kinase activity and, except for FGFR-4, multiple splice isoforms, and FGFR-5, which lacks an intracellular kinase domain. There is growing evidence that FGFRs can be important for regulation of glucose and lipid homeostasis. The overexpression of a dominant negative form of FGFR-1 in ? cells leads to diabetes in mice, which thus implies that proper FGF signaling is required for normal ? cell function and glycemia maintenance. FGFR-2 appears to be a key molecule during pancreatic development. Moreover, FGFR-4 has been implicated in cholesterol metabolism and bile acid synthesis.
FGF-19, has been shown to cause resistance to diet-induced obesity and insulin desensitization and to improve insulin, glucose, and lipid profiles in diabetic rodents. Since these effects, at least in part, are mediated through the observed changes in metabolic rates, FGF-19 can be considered as a regulator of energy expenditure.
FGF-21 is preferentially expressed in liver, but an exact knowledge of FGF-21 bioactivity and its mode of action have been lacking to date. FGF-21 is a potent activator of glucose uptake on adipocytes, protects animals from diet-induced obesity when overexpressed in transgenic mice, and lowers blood glucose and triglyceride levels when therapeutically administered to diabetic rodents.

GH is a member of the prolactin family of hormones which play an important role in growth control. The gene, along with four other related genes, is located at the GH 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 GHs, 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 GH locus. Mutations in or deletions of the gene lead to GH deficiency and short stature.

A 88-kDa progranulin, also called proepithelin and PC cell-derived growth factor, is a single precursor protein of granulins which are a family of secreted, glycosylated peptides that are cleaved from a single precursor protein with 7.5 repeats of a highly conserved 12-cysteine granulin/epithelin motif. Granulins are a variety of active, 6 kDa peptides and named granulin A (epithelin 1), granulin B (epithelin 2), granulin C, etc. Both the peptides and intact progranulin protein regulate cell growth. However, different members of the granulin protein family may act as inhibitors, stimulators, or have dual actions on cell growth. Granulin family members are important in normal development, wound healing, and tumorigenesis.

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.

Growth Differentiation Factor-7 (GDF-7) belongs to the BMP family of TGF-b superfamily proteins. GDF7 elicits its bioactivity via a heterodimeric receptor complex comprised of a type 1 (BMPR-IB) and a type II (BMPR-II or Activin RII) serine/threonine kinase receptor. GDF7 signaling results in the phosphorylation and activation of Smad proteins. GDF-7 is also involved in tendon and ligament formation and repair. In addition, GDF7 regulates bone formation, mesenchymal stem cell differentiation, neuronal differentiation, and axon guidance.

Vascular endothelial growth factor is an important signaling protein involved in both vasculogenesis and angiogenesis. As its name implies, VEGF activity has been mostly studied on cells of the vascular endothelium, although it does have effects on a number of other cell types (e.g. stimulation monocyte/ macrophagemigration, neurons, cancer cells, kidney epithelial cells ).VEGF mediates increased vascular permeability, induces angiogenesis, vasculogenesis and endothelial cell growth, promotes cell migration, and inhibits apoptosis. In vitro, VEGF has been shown to stimulate endothelial cell mitogenesisand cell migration. VEGF is also a vasodilator and increases microvascular permeability and was originally referred to as vascular permeability factor.
Elevated levels of this protein are linked to POEMS syndrome, also known as Crow-Fukase syndrome. Mutations in this gene have been associated with proliferative and nonproliferative diabetic retinopathy.

The somatomedins, or insulin-like growth factors (IGFs), comprise a family of peptides that play important roles in mammalian growth and development. IGF1 mediates many of the growth-promoting effects of growth hormone (GH; MIM 139250). Early studies showed that growth hormone did not directly stimulate the incorporation of sulfate into cartilage, but rather acted through a serum factor, termed 'sulfation factor,' which later became known as 'somatomedin' (Daughaday et al., 1972). Three main somatomedins have been characterized: somatomedin C (IGF1), somatomedin A (IGF2; MIM 147470), and somatomedin B (MIM 193190) (Rotwein, 1986; Rosenfeld, 2003).

The heat-shock response is elicited by exposure of cells to thermal and chemical stress and through the activation of HSFs (heat shock factors) results in the elevated expression of heat-shock induced genes. Heat shock factor binding protein-1 (HSBP1), is a 76-amino-acid protein that binds to heat shock factor 1(HSF1), which is a transcription factor involved in the HS response. During HS response, HSF1 undergoes conformational transition from an inert non-DNA-binding monomer to active functional trimers. HSBP1 is nuclear-localized and interacts with the active trimeric state of HSF1 to negatively regulate HSF1 DNA-binding activity. Overexpression of HSBP1 in mammalian cells represses the transactivation activity of HSF1. When overexpressed in C.elegans HSBP1 has severe effects on survival of the animals after thermal and chemical stress consistent with a role of HSBP1 as a negative regulator of heat shock response.

HDL is a complex of lipids and proteins in approximately equal amounts that functions as a transporter of cholesterol in the blood. HDL is the smallest of the lipoprotein particles; it’s the densest because it contains the highest proportion of protein. The liver synthesizes these lipoproteins as complexes of apolipoproteins and phospholipid, which bear a resemblance to cholesterol-free flattened spherical lipoprotein particles. They pick up cholesterol; carry it internally, from cells by interaction with the ATP Binding Cassette Transporter A1. Lecithin-cholesterol acyltransferase (plasma enzyme) converts the free cholesterol into cholesteryl ester (a more hydrophobic form of cholesterol) which is then sequestered into the core of the lipoprotein particle ultimately making the newly synthesized HDL spherical. They increase in size as they pass through the bloodstream and integrate more cholesterol and phospholipid molecules from cells and other lipoproteins, for instance by the interaction with the ABCG1 transporter and the phospholipid transport protein. HDL transports their cholesterol generally to the liver or steroidogenic organs such as adrenals, ovary and testes by direct and indirect pathways. The release of HDL cholesterol to adrenals, ovaries and testes is important for the synthesis of steroid hormones. Since the triglycerides are not stable in HDL, they’re degraded by hepatic lipase in order that finally small HDL particles are left which resume the uptake of cholesterol from cells. The cholesterol supplied to the liver is excreted into the bile and consequently intestine either directly or indirectly after conversion into bile acids. High levels of HDL are associated with a decreased risk of atherosclerosis and coronary heart disease.

GMFB is part of the GMF subfamily of the larger actin-binding protein ADF family. GMFB is phosphorylated after phorbol ester stimulation, and is crucial for the nervous system. GMFB causes brain cell differentiation, stimulates neural regeneration and inhibits tumor cell proliferation. GMFB overexpression in astrocytes results in the increase of BDNF production. GMFB expression is increased by exercise, thus BDNF is important for exercise-induction of BDNF.

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.

The FGFs are a family of more than 20 small (~17–26 kDa) secreted peptides. The initial characterization of these proteins focused on their ability to stimulate fibroblast proliferation. This mitogenic activity was mediated through FGF receptors (FGFRs) 1, 2, or 3. A fourth closely related tyrosine kinase receptor (FGFR4) was able to bind the FGFs but did not lead to a mitogenic response.
FGFs modulate cellular activity via at least 5 distinct subfamilies of high-affinity FGF receptors (FGFRs): FGFR-1, -2, -3, and -4, all with intrinsic tyrosine kinase activity and, except for FGFR-4, multiple splice isoforms, and FGFR-5, which lacks an intracellular kinase domain. There is growing evidence that FGFRs can be important for regulation of glucose and lipid homeostasis. The overexpression of a dominant negative form of FGFR-1 in ? cells leads to diabetes in mice, which thus implies that proper FGF signaling is required for normal ? cell function and glycemia maintenance. FGFR-2 appears to be a key molecule during pancreatic development. Moreover, FGFR-4 has been implicated in cholesterol metabolism and bile acid synthesis.
FGF-19, has been shown to cause resistance to diet-induced obesity and insulin desensitization and to improve insulin, glucose, and lipid profiles in diabetic rodents. Since these effects, at least in part, are mediated through the observed changes in metabolic rates, FGF-19 can be considered as a regulator of energy expenditure.
FGF-21 is preferentially expressed in liver, but an exact knowledge of FGF-21 bioactivity and its mode of action have been lacking to date. FGF-21 is a potent activator of glucose uptake on adipocytes, protects animals from diet-induced obesity when overexpressed in transgenic mice, and lowers blood glucose and triglyceride levels when therapeutically administered to diabetic rodents.

Fibroblast Growth Factor 17 (FGF17) belongs to the fibroblast growth factor (FGF) family. FGF family members have broad mitogenic and cell survival activities, and are involved in various biological processes including embryonic development cell growth, morphogenesis, tissue repair, tumor growth and invasion. The FGF17 gene is highly expressed in the cerebellum and cortex. The mouse homolog of the FGF17 gene is localized to specific sites in the midline structures of the forebrain, the midbrain-hindbrain junction, developing skeleton and developing arteries, suggesting a role in central nervous system, bone and vascular development.

Fibroblast Growth Factor-6 (FGF6) belongs to the fibroblast growth factor (FGF) family. FGF family members possess extensive mitogenic and cell survival functions, and are involved in various biological processes, including embryonic development, cell growth, morphogenesis, tissue repair, tumor growth and invasion. The FGF6 gene displayes oncogenic transforming activity when transfected into mammalian cells. The mouse homolog of the FGF6 gene displays a restricted expression profile predominantly in the myogenic lineage, suggesting a role in muscle regeneration or differentiation.

Hepatitis B virus is the main cause for human liver disease, chronic infection frequently causes liver cancer and cirrhosis. The HBV core gene codes 2 distinct protein products, a 21.5-kDa protein being assembled to form nucleocapsid particles designated HBcAg, which wraps the viral DNA as well as the viral polymerase and RNase H, and a precore protein, designated as HBeAg, which is directly to the endoplasmic reticulum, processed at N- and C-terminally and secreted as non-particulate e-anitgen (HBeAg). The pre-core protein contains an extra 29 N-terminal amino acids, serving as a signal peptide to direct the nascent polypeptide into secretory pathway. After the secretion, mature HBeAg is deleted at the residue 149 C-terminally and retains 10 precore residues N-terminally. HBcAg and HBeAg are distinctly recognized by antibodies but highly cross-reactive at the T-cell level.
The e antigen is found in the circulation, it is found during the active HBV infection, positive result indicates the risk for contagiousness, and is also used as indicator for the effectiveness of HBV treatment. Positive anti-HBeAg specifies an active stage of acute HBV infection that is in its final stages, the risk for contagiousness is dramatically reduced.

GDF-5 is a member of the bone morphogenetic protein (BMP) family and the TGF-beta superfamily. This group of proteins is characterized by a polybasic proteolytic processing site which is cleaved to produce a mature protein containing seven conserved cysteine residues. The members of this family are regulators of cell growth and differentiation in both embryonic and adult tissues. Mutations in this gene are associated with acromesomelic dysplasia, Hunter-Thompson type; brachydactyly, type C; and chondrodysplasia, Grebe type. These associations confirm that the gene product plays a role in skeletal development.

The mammaglobin gene was first identified using a differential screening approach directed at the isolation of novel, human breast cancer-associated genes. Mammaglobin encodes a 10 kDa glycoprotein and is distantly relaetd to a family of epithelial secretory proteins that includes rat estramustine-binding protein/prostatein and human Clara cell 10 kDa protein (CC10)/uteroglobin. Mammaglobin, a mammary-specific member of the uterglobin family, is known to be overexpressed in human breast cancer. Studies suggest that mammaglobin is one of the first relatively mammary-specific and mammary-sensitive markers (85%). Mammaglobin may be valuable used in a panel with BRST-2 (GCDFP-15) and ER in evaluating tumors of unknown primary sites.
SCGB2A2 (the mammaglobin gene) is located on chromosome 11, at locus 11q13. SCGB2A2 is member of the secretoglobin superfamily of which is a group of small dimeric secreted and sometimes glycosylated proteins. Expressed mainly in mucosa, secretoglobins appear to be involved in cell signalling, immune response, chemotaxis, and might also serve as transporters for steroid hormones in humans.

Rho Guanine Nucleotide Exchange Factor 39, also known as ARHGEF39, is a protein coding gene which owns one DH (DBL-homology) domain and one PH domain. ARHGEF39 encourages cell proliferation.