Search results

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 INS desensitization and to improve INS, 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.

Epiregulin is part of the EGF family. Epiregulin functions as a ligand of EGFR, as well as a ligand of most members of the ERBB (v-erb-b2 oncogene homolog) family of tyrosine-kinase receptors.Epiregulin is expressed mostly in the placenta and peripheral blood leukocytes and in specific carcinomas of the bladder, lung, kidney and colon. Epiregulin stimulates the proliferation of keratinocytes, hepatocytes, fibroblasts and vascular smooth muscle cells. Epiregulin inhibits the growth of several tumor-derived epithelial cell lines. Human Epiregulin is initially synthesized as a glycosylated 19.0 kDa transmembrane precursor protein, which is processed by proteolytic cleavage to produce a 6.0 kDa mature secreted sequence.

Flagellin arranges itself in a hollow cylinder to create the filament in bacterial flagellum. Flagellin is the key substituent of bacterial flagellum, and is found in large quantities on almost all flagellated bacteria.

Actin is a muscle protein localized in the I band of the myofibrils; acting along with myosin, it is responsible for contraction and relaxation of muscle. Each actin protomer binds one molecule of ATP and has one high affinity site for either calcium or magnesium ions, as well as several low affinity sites. Actin exists as a monomer in low salt concentrations, but filaments form rapidly as salt concentration rises, with the consequent hydrolysis of ATP. It occurs in globular (G-actin) and fibrous (F-actin) forms. Actin is found in all eukaryotic cells (except for nematode sperm). Actin is one of the most highly-conserved proteins, differing by no more than 20% in species as diverse as algae and humans. Its other functions include cell motility, cell division and cytokinesis, vesicle and organelle movement, cell signaling, and the establishment and maintenance of cell junctions and cell shape.

Leukocyte Cell Derived Chemotaxin 1 (214-333 a.a.), also known as LECT1, is a glycosylated transmembrane protein which is cleaved to form a mature, secreted protein. The mature protein encourages chondrocyte growth and inhibits angiogenesis. The mature protein takes part in endochondral bone development by permitting cartilaginous anlagen to be vascularized and replaced by bone. LECT1 is expressed in the avascular area of prehypertrophic cartilage and its expression reduces during vascular invasion and chondrocyte hypertrophy.

Ferritin is the main intracellular iron storage protein in prokaryotes and eukaryotes. Ferritin’s major functions are the storage of iron in a soluble and nontoxic state and its release in a controlled fashion. An iron-containing protein complex is found mostly in the intestinal mucosa, spleen, and liver. Ferritin is composed of 24 subunits of the heavy and light chains. Variation in ferritin subunit composition may influence the rates of iron uptake and release in different tissues. Defects in the light chain ferritin gene are linked to a number of neurodegenerative diseases and hyperferritinemia-cataract syndrome. The genes that encode the light and heavy chains are on located different chromosomes. The light chain genes are in chromosome region 19q13.3-q13.4 whilst those for the heavy chain are in chromosome region 11q12-q13. Ferritin is shaped like a hollow sphere, inside which the iron is stored in the Fe(III) oxidation state. The iron is integrated in the mineral ferrihydrite, [FeO(OH)]8[FeO(H2PO4)], which is attached to the inner wall of the sphere. To release iron once the body needs it, the iron must be altered from the Fe(III) to the Fe(II) oxidation state. Subsequently, the iron leaves through channels in the spherical structure. Therefore, the structure of ferritin is tremendously important for the protein's ability to store and release iron in a controlled mode.
The amount of ferritin in the blood (serum ferritin level) is directly related to the amount of iron stored in the body. The body has a "buffer" against iron deficiency (if the blood has too little iron, ferritin can release more) and, to a lesser extent, iron overload (if the blood and tissues of the body have too much iron, ferritin can help store the excess iron).

Adipocyte fatty acid binding protein FABP4 is a 15 kDa member of the intracellular fatty acid binding protein (FABP) family, which is known for the ability to bind fatty acids and related compounds (bile acids or retinoids) in an internal cavity. FABP4 is expressed in a differentiation-dependent fashion in adipocytes and is a critical gene in the regulation of the biological function of these cells.
In mice, targeted mutations in FABP4 provide significant protection from hyperinsulinemia and insulin resistance in the context of both dietary and genetic obesity. Adipocytes obtained from FABP4-deficient mice also have reduced efficiency of ipolysis in vitro and in vivo, and these mice exhibited moderately improved systemic dyslipidemia. Recent studies also demonstrated FABP4 expression in macrophages upon differentiation and activation. In these cells, FABP4 modulates inflammatory responses and cholesterol ester accumulation, and total or macrophage-specific FABP4 deficiency confers dramatic protection against atherosclerosis in the apoE-/- mice. These results indicate a central role for FABP4 in the development of major components of the metabolic syndrome through its distinct actions in adipocytes and macrophages.

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.

FKBP14 enzyme accelerates the folding of proteins during protein synthesis. FKBP14 contains 2 EF-hand domains and one PPIase FKBP-type domain. Truncation of the amino-terminus of FKBP14 significantly decreases peptidyl prolyl cis-trans isomerase activity, therefore implicating that the PPIase FKBP-type domain must be located at the N-terminus.

Basic fibroblast growth factor is a member of the fibroblast growth factor (FGF) family. FGF family members possess broad mitogenic and cell survival activities, and are involved in a variety of biological processes, including embryonic development, cell growth, morphogenesis, tissue repair, tumor growth and invasion. This protein functions as a modifier of endothelial cell migration and proliferation, as well as an angiogenic factor. It acts as a mitogen for a variety of mesoderm- and neuroectoderm-derived cells in vitro, thus is thought to be involved in organogenesis. Three alternatively spliced variants encoding different isoforms have been described. The heparin-binding growth factors are angiogenic agents in vivo and are potent mitogens for a variety of cell types in vitro. There are differences in the tissue distribution and concentration of these 2 growth factors.

Vitronectin (VTN) which is a part of the pexin family is a cell adhesion and spreading factor found in serum and tissues. VTN interacts with glycosaminoglycans and proteoglycans. VTN inhibits the membrane-damaging effect of the terminal cytolytic complement pathway and binds to numerous serpin serine protease inhibitors. Scientists have been noticed an over expression of VTN, integrins and plasminogen in migrating cells during wound healing.

Procollagen C-endopeptidase enhancer 1, also known as PCOLCE binds to the C-terminal propeptide of type I procollagen and enhances procollagen C-proteinase activity. In addition, C-terminal processed part of PCPE (CT-PCPE) has a metalloproteinase inhibitory activity. Among the diseases which are associated with PCOLCE: bone fracture & oculopharyngeal muscular dystrophy.

GCSF is a cytokine that controls the production, differentiation, and function of granulocytes. The active protein is found extracellularly. Three transcript variants encoding three different isoforms have been found for this gene. Granulocyte/macrophage colony-stimulating factors are cytokines that act in hematopoiesis by controlling the production, differentiation, and function of 2 related white cell populations of the blood, the granulocytes and the monocytes-macrophages. This csf induces granulocytes.

TFPI is a protease inhibitor which controls the tissue factor (TF)-dependent pathway of blood coagulation. The coagulation process starts with the creation of a factor VIIa-TF complex, that proteolytically triggers additional proteases (factors IX and X) and eventually results in a fibrin clot. TFPI inhibits the activated factor X and VIIa-TF proteases in an autoregulatory loop. TFPI is glycosylated and predominantly located in the vascular endothelium and plasma in both free forms and complexed with plasma lipoproteins. A number of alternatively spliced transcript variants of this gene have are known, however the full-length nature of several of these variants were not yet established.

Syndecan-4 is a type I integral membrane heparan sulfate proteoglycan (HSPG), which was originally isolated from cloned rat microvascular endothelial cells as an antithrombin-binding molecule, and is now known to be a member of the syndecan family. Syndecan-4 binds to basic fibroblast growth factor (bFGF), midkine, and tissue factor pathway inhibitor via its heparan sulfate chains, and is thought to be involved in various biologic functions such as signaling of bFGF, anticoagulation, and focal adhesion formation. A previous study demonstrated that syndecan-4 is expressed in various tissues, and its level of expression in the kidney is stronger than those of other syndecan family members. Thus, syndecan-4 is thought to play certain roles in maintaining renal function. Moreover, it has been reported that proteoglycans, especially sulfated proteoglycans, are involved in organogenesis of the kidney.

EFNA1 belongs to the ephrin (EPH) family. The EPH subfamily is the biggest group of receptor protein kinases and they take part in vital nervous system function and development.

Carcinoembryonic Antigen-Related Cell Adhesion Molecule 1 (CEACAM1) belongs to the carcinoembryonic antigen (CEA) gene family which is a part of the immunoglobulin superfamily. CEACAM1 is a cell adhesion protein which mediates homophilic cell adhesion in a calcium-independent way. CEACAM1 is a surface glycoprotein expressed on various blood cells, epithelial cells, and vascular cells. CEACAM1 functions as coinhibitory receptor in immune response, and plays a role also as an activator during angiogenesis.

Carcinoembryonic Antigen-Related Cell Adhesion Molecule 8 (CEACAM8) is a cell surface glycoprotein which takes part in cell adhesion in a calciumindependent manner.CEACAM8mediates heterophilic cell adhesion with other carcinoembryonic antigen-related celladhesion molecules (CEACAM6 for example).CEACAM8main role is cell migration,cell adhesion, and pathogen binding.CEACAM-8 isexpressed mainly on the surface of human peripheral blood eosinophils isolated from healthy individuals andused as granulocyte marker.

CETN1 is an EF-hand type Ca2+-binding protein. CETN1 is localized to the centrosome of interphase cells, and reorganizes the region of the spindle poles during mitosis, reflecting the dynamic behavior of the centrosome during the cell cycle. CETN1 has a vital part in the determination of centrosome position and isolation, and in the course of microtubule separating.

Basic fibroblast growth factor is a member of the fibroblast growth factor (FGF) family. FGF family members possess broad mitogenic and cell survival activities, and are involved in a variety of biological processes, including embryonic development, cell growth, morphogenesis, tissue repair, tumor growth and invasion. This protein functions as a modifier of endothelial cell migration and proliferation, as well as an angiogenic factor. It acts as a mitogen for a variety of mesoderm- and neuroectoderm-derived cells in vitro, thus is thought to be involved in organogenesis. Three alternatively spliced variants encoding different isoforms have been described. The HPR -binding growth factors are angiogenic agents in vivo and are potent mitogens for a variety of cell types in vitro. There are differences in the tissue distribution and concentration of these 2 growth factors.

FGL1 belongs to the fibrinogen family. Fibrinogen Like 1 is homologous to the carboxy terminus of the fibrinogen beta- and gamma- subunits which comprises the 4 conserved cysteines of fibrinogens and fibrinogen related proteins. FGL1 lacks the platelet-binding site, cross-linking region and a thrombin-sensitive site which are necessary for fibrin clot formation. Fibrinogen takes part in the development of hepatocellular carcinomas.

ARPC5 is a 151 amino acid subunit of the Arp2/3 complex. ARPC5 is believed to have a role in maintaining the integrity of Arp2/3. ARPC5 is a substrate for MAPKAPK-2 which, via phosphorylation of ARPC5, may participate in Arp2/3 regulatory functions and remodeling of the Actin cytoskeleton.

GREM1 belongs to the BMP (bone morphogenic protein) antagonist family. Like BMPs, BMP antagonists comprise cystine knots and usually form homo- and heterodimers. The CAN (cerberus and dan) subfamily of BMP antagonists, to which GREM1 belongs, is characterized by a C-terminal cystine knot with an eight-membered ring. The antagonistic effect of the secreted glycosylated protein is because of its direct binding to BMP proteins. As an antagonist of BMP, GREM1 takes a place in regulating organogenesis, body patterning, and tissue differentiation. In mouse, GREM1 has been shown to convey the sonic hedgehog (SHH) signal from the polarizing region to the apical ectodermal ridge during limb bud outgrowth. Alternatively merged transcript variants encoding different isoforms have been found for this gene.