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Mediator Complex Subunit 27 (MED27) is a subunit of the CRSP (cofactor required for SP1 activation) complex, which, together with TFIID, is necessary for efficient activation by SP1. MED27 is a component of the Mediator complex, a coactivator involved in the regulated transcription of virtually all RNA polymerase II-dependent genes. MED27 protein is also a component of other multisubunit complexes such as the thyroid hormone receptor-(TR-) associated proteins which interact with TR and facilitate TR function on DNA templates in conjunction with initiation factors and cofactors. The activation of MED27 gene transcription is a multistep process, which is triggered by factors that identify transcriptional enhancer sites in DNA.

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.

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 epidermal growth factor receptor (EGF R) subfamily of receptor tyrosine kinases comprises four members: EGF R (also known as HER1, ErbB1 or ErbB), ErbB2 (Neu, HER-2), ErbB3 (HER-3), and ErbB4 (HER-4). All family members are type I transmembrane glycoprotein that has an extracellular domain which contains two cysteine-rich domains separated by a spacer region that is involved in ligand-binding, and a cytoplasmic domain which has a membrane-proximal tyrosine kinase domain and a C-terminal tail with multiple tyrosine autophosphorylation sites. The human EGF R gene encodes a 1210 amino acid (aa) residue precursor with a 24 aa putative signal peptide, a 621 aa extracellular domain, a 23 aa transmembrane domain, and a 542 aa cytoplasmic domain. EGF R has been shown to bind a subset of the EGF family ligands, including EGF, amphiregulin, TGF-a , betacellulin, epiregulin, heparin-binding EGF and neuregulin-2 in the absence of a co-receptor. Ligand binding induces EGF R homodimerization as well as heterdimerization with ErbB2, resulting in kinase activation, tyrosine phosphorylation and cell signaling. EGF R can also be recruited to form heterodimers with the ligand-activated ErbB3 or ErbB4. EGF R signaling has been shown to regulate multiple biological functions including cell proliferation, differentiation, motility and apoptosis. In addition, EGF R signaling has also been shown to play a role in carcinogenesis.

XIAP Associated Factor 1 (XAF1) is a protein which binds to and counteracts the inhibitory effect of a member of the IAP (inhibitor of apoptosis) protein family. IAP proteins bind to and inhibit caspases which are activated in the course of apoptosis. The ratio of IAPs and proteins which interfere with their activity, such as the XAF1 protein, influence the progress of the apoptosis signaling pathway. Additionally, XAF1 inhibits anti-caspase activity of BIRC4. XAF1 induces cleavage and inactivation of BIRC4 independent of caspase activation. Furthermore, XAF1 mediates TNF-alpha-induced apoptosis and is involved in apoptosis in trophoblast cells.

TNFR1 belongs to the TNF-receptor superfamily. TNFR1 is a receptor for TNFSF2/TNF-alpha and homotrimeric TNFSF1/lymphotoxin-alpha.
There are 2 types of soluble TNF receptors: sTNFR-I and sTNFR-II, which act to neutralize the biological activities of TNF alpha and TNF beta. The levels of these soluble receptors seem to increase as a result of shedding of the extracellular domains of the membrane bound receptors. TNF-a, TNFR1 and TNFR2 have roles in cellular differentiation. TNFR1 and TNFR2 function in cell type-specific renal injury.
TNFR1 is capable of signaling both cell survival and apoptosis. TNFR1-induced apoptosis requires 2 sequential signaling complexes. TNFR1 is capable of activating NF-kappaB, mediate apoptosis, and function as a regulator of inflammation. Oxidative stress promotes TNFR1 and TNFR2 self-interaction, ligand-independent and enhanced ligand-dependent TNF signaling. TNFR1 contributes to the induction of non-cytocidal TNF effects including anti-viral state and activation of the acid sphingomyelinase. Human TNFR1 has a major region which controls cell surface expression. High levels of soluble TNF receptors are found in the amniotic fluid of pregnant women.
Germline mutations of the extracellular domains of TNFR1 are linked to the autosomal dominant periodic fever syndrome. The impaired receptor clearance is believed to be a mechanism of the disease. Familial hibernian fever (FHF) is caused by defects in TNFRSF1A gene.

CDNF is a member of the ARMET family and acts as a trophic factor for neurons. CDNF inhibits the 6-hydroxy (6-OHDA)-induced degeneration of neurons. When CDNF controlled after 6-OHDA-lesioning, it reestablishes the function and inhibits the degeneration of neurons in substantia nigra. CDNF is universally expressed in neuronal and non-neuronal tissues. The highest levels in the brain are found in the optic nerve and corpus callosum.

Stem cell factor / KIT ligand (SCF) is a cytokine which binds CD117(c-Kit). SCF is also known as "steel factor" or "c-kit ligand". SCF exists in two forms, cell surface bound SCF and soluble (or free) SCF. Soluble SCF is produced by the cleavage of surface bound SCF by metalloproteases.
SCF is a growth factor important for the survival, proliferation, and differentiation of hematopoietic stem cells and other hematopoietic progenitor cells. One of its roles is to change the BFU-E (burst-forming unit-erythroid) cells, which are the earliest erythrocyte precursors in the erythrocytic series, into the CFU-E (colony-forming unit-erythroid).

EIF4E is part of the eukaryotic initiation factor 4 families, controls translation of maternal mRNAs in early embryos before the onset of zygotic transcription. EIF4E identifies and binds to the 7 methyl GTP cap structure of eukaryotic mRNAs, thus modulates the initiation of translation. EIF4E enables ribosome binding by inducing the unwinding of the mRNAs secondary structures.

Myeloid leukemia factor 1 (MLF1) is a member of the MLF family, and is a widely expressed negative regulator of cell cycle progression functioning upstream of the tumor suppressor p53. MLF1 hinders the erythropoietin-induced erythroid terminal differentiation by averting cells from exiting the cell cycle through suppression of CDKN1B/p27Kip1 levels. MLF1 generally functions in multi-potent progenitor cells, and its dysregulation may be to some extent responsible for leukemogenesis. Translocations between the MLF1 gene and nucleophosmin are linked to myelodysplastic syndrome and acute myeloid leukemia.

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-1a/CXCL12a and SDF-1b/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.

NT3 a member of the neurotrophin family, that controls survival and differentiation of mammalian neurons. This protein is closely related to both nerve growth factor and brain-derived neurotrophic factor. It may be involved in the maintenance of the adult nervous system, and may affect development of neurons in the embryo when it is expressed in human placenta. NTF3-deficient mice generated by gene targeting display severe movement defects of the limbs. The mature peptide of this protein is identical in all mammals examined including human, pig, rat and mouse.

SF3B14 is a 125 amino acid nuclear protein which is a component of the splicing factor 3b complex. Splicing factor 3b is involved with s with both the U2 and U11/U12 small nuclear ribonucleoprotein complexes (U2 snRNP) of spliceosomes. SF3B14 which is required for the splicing of pre-mRNA enters the spliceosome and connect with the pre-mRNA branch site facilitating the interaction of snRNP with the branch sites of U2 and U12 of the 17S U2 and the 18S U11/U12 snRNP complex.

proBDNF (the precursor form of Brain-derived neurotrophic factor) interacts preferentially with p75NTR (the pan-neurotrophin receptor p75) and vps10p domain-containing receptor sortilin and induces neuronal apoptosis, while the mature BDNF selectively binds with great affinity to the TrkB kinase receptor and promotes the survival, growth and differentiation of neurons. Since proneurotrophins and mature neurotrophins bring forth opposite biological effects, proBDNF cleavage in the neuronal system is regulated in a specific and cell-context dependent manner. proBDNF has an important role in negative regulation of neurotrophic actions in the brain.

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.

Excess adiposity is the most important risk in the development of type 2 diabetes mellitus (T2DM). Adipose tissue produces several proteins (adipocytokines) such as leptin, adiponectin, resistin, tumor necrosis factor-a, and IL-6, that modulate sensitivity and appear to play an important role in the pathogenesis, diabetes, dyslipidemia, inflammation, and atherosclerosis. Visfatin, also known as pre-B cell colony-enhancing factor (PBEF), is a cytokine that is highly expressed in visceral fat and was originally isolated as a secreted factor that synergizes with IL-7 and stem cell factors to promote the growth of B cell precursors. Visfatin homologs have been identified in carp, invertebrate mollusks, and bacteria, as well as in vertebrates, including humans and the mouse. It has been postulated to play a role in innate immunity.
Visfatin exerts mimetic effects that are dose-dependent and quantitatively similar to stimulating muscle and adipocyte glucose transport, and in inhibiting hepatocyte glucose production. Intravenous injection of recombinant visfatin in mice decreased plasma glucose in a dose-dependent fashion. In keeping with its mimetic effects, visfatin was as effective in reducing hyperglycemia in deficient diabetic mice. Visfatin was also found to be bound to and activate receptor, causing receptor phosphorylation and the activation of downstream signaling molecules. However, visfatin did not compete for binding to the receptor, indicating that the two proteins were recognized by different regions of the receptor. Thus, visfatin might play a role in glucose homeostasis and dysregulation in biosynthesis or signal transduction, and might contribute to the pathogenesis of diabetes.

Complement C1q Tumor Necrosis Factor-Related Protein 5 (C1QTNF5) encodes a short-chain collagen which is expressed mainly in sub-retinal pigment epithelium, ciliary epithelium and adipose tissue. C1QTNF5 is increased in mtDNA-depleted myocytes and stimulates the phosphorylation of AMP activated protein kinase. C1QTNF5 takespart in the adhesion of the retinal pigment epithelium (RPE) to the Bruch Membrane. Mutations in C1QTNF5 have been associated with late-onset retinal degeneration.

Mitochondrial Ribosome Recycling Factor (MRRF) is a member of the RRF family. MRRF attaches to the large ribosomal subunit in the cleft which has a peptidyl transferase center. MRRF controls the release of ribosome from messenger RNA at the termination of protein biosynthesis. Also, it may intensify the efficacy of translation by recycling ribosome from one round of translation to another.

Intrinsic Factor is a member of the cobalamin transport protein family. It encodes a glycoprotein secreted by parietal cells of the gastric mucosa and is required for adequate absorption of vitamin B12 in the terminal ileum. Vitamin B12 is essential for erythrocyte maturation and mutations in the Intrinsic Factor may lead to congenital pernicious anemia. Upon entry into the stomach, vitamin B12 binds to one of two B12 binding proteins present in the gastric fluid. In the less acidic environment of the small intestine, these proteins dissociate from the vitamin, allowing it to bind to intrinsic factor and enter the portal circulation through a receptor in the ileal mucosa specific for the B12-intrinsic factor complex.

Ciliary Neurotrophic Factor Receptor, also known as CNTFR is a member of the type I cytokine receptor family. CNTFR binds to CNTF.The alpha subunit provides the receptor specificity.Sole nucleotide polymorphisms in CNTFR has been associated with variations in muscle strength, in addition to early onset of eating disorders.

NANOG is a multidomain homeobox transcription factor which functions to maintain the undifferentiated state of pluripotent stem cells. NANOG expression counteracts the differentiation-promoting signals induced by the extrinsic factors LIF, Stat3 and BMP. Once NANOG expression is downregulated, cell differentiation can proceed. Proteins which regulate NANOG expression include transcription factors Oct4, SOX2, FoxD3, and Tcf3 and tumor suppressor p53.

Stromal Cell-Derived Factor 2 (SDF2) is a secretory protein which is partly similar to the hydrophilic segments of yeast mannosyltransferases. SDF2 protein’s expression is ubiquitous and the gene is rather conserved among mammals. SDF2is a protein-coding gene whose alternative splicing results in coding and non-coding variants.

MAFK is a member of the bZIP family and Maf subfamily. Members from Maf family of basic region/leucine zipper (bZIP) transcription factors influence transcription in a positive or negative way, depending on their protein associate and the context of the target promoter. Small Mafs act as transcriptional repressors when they dimerize among themselves. Yet, they seem to function as transcriptional activators by dimerizing with other basic-zipper proteins and employing them to specific DNA-binding sites.

WIF1 binds to wnt proteins and inhibits their activities. WIF1 plays a role in mesoderm segmentation. WNT proteins are extracellular signaling molecules that take part in the control of embryonic development & cancer. WIF1 protein contains a WNT inhibitory factor (WIF) domain and 5 epidermal growth factor (EGF)-like domains. WIF1 takes part in mesoderm segmentation. WIF1 protein is found to be present in fish, amphibia and mammals. WIF1 is a recurrent target in human salivary gland oncogenesis. Downregulation of WIF1 takes part in the development and progression of pleomorphic adenomas. WIF1 is a tumor suppressor, specifically in nonfunctioning pituitary tumors.