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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 desensitization and to improve, 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.

The somatomedins, or insulin-like growth factors (IGFs), comprise a family of peptides that takes part in mammalian growth and development. IGF1 mediates various 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). 3 main somatomedins have been characterized: somatomedin C (IGF1), somatomedin A (IGF2; MIM 147470), and somatomedin B (MIM 193190) (Rotwein, 1986; Rosenfeld, 2003).

Parathyroid hormone (PTH), or parathormone, is secreted by the parathyroid glands as a polypeptide containing 84 amino acids. It acts to increase the concentration of calcium in the blood, whereas calcitonin (a hormone produced by the parafollicular cells of the thyroid gland) acts to decrease calcium concentration. PTH acts to increase the concentration of calcium in the blood by acting upon parathyroid hormone receptor in three parts of the body: In the bones- It enhances the release of calcium from the large reservoir contained in the bones. Bone resorption is the normal destruction of bone by osteoclasts, which are indirectly stimulated by PTH. Stimulation is indirect since osteoclasts do not have a receptor for PTH; rather, PTH binds to osteoblasts, the cells responsible for creating bone. Binding stimulates osteoblasts to increase their expression of RANKL, which can bind to osteoclast precursors containing RANK, a receptor for RANKL. The binding of RANKL to RANK stimulates these precursors to fuse, forming new osteoclasts which ultimately enhances the resorption of bone. In the kidney- It enhances active reabsorption of calcium from distal tubules and the thick ascending limb. In the intestine- It enhances the absorption of calcium in the intestine by increasing the production of vitamin D and upregulating the enzyme responsible for 1-alpha hydroxylation of 25-hydroxy vitamin D, converting vitamin D to its active form (1,25-dihydroxy vitamin D) which effects the actual absorption of calcium (as Ca2+ ions) by the intestine via calbindin.

Omentin is a recently recognized gene highly localized to the mental tissue (visceral adipose tissue). Omentin is present in the stromal vascular cells in the adipose tissue rather than in the adipocytes. Omentin is predominantly expressed in the visceral adipose tissue than the subcutaneous tissue, with the omentin mRNA being 150 times higher in the visceral adipose tissue. Omentin has also been detected in human blood using western blot analysis, and seems to increase insulin-stimulated glucose uptake in 3T3-L1 adipocytes in mice. Omentin seems to increase Akt phosphorylation irrespective of insulin presence. Its role in glucose metabolism and obesity remains to be described; an insulin-sensitizing action is possible.Differences in Omentin expression has been noted in adipose tissue from normals and patients with inflammatory bowel disease although its significance is unknown.

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, insulin resistance, and cancer.

B-Cell Maturation Antigen or TNFRSF17 or tumor necrosis factor receptor superfamily member 17, is part of the TNF receptor protein family. This protein is a TNFSF13B/BLyS/BAFF, TNFSF13/APRIL & promotes B-cell survival receptor. TNFRSF17 has a crucial part in the humoral immunity regulation. This protein is responsible for the activation of NF-kappa-B & JNK.

PPIF is a part of the peptidyl-prolyl cis-trans isomerase (PPIase) family. PPIF accelerates the folding of proteins. It catalyzes the cis-trans isomerization of proline imidic peptide bonds in oligopeptides. PPIF is key component of the mitochondrial permeability transition pore in the inner mitochondrial membrane. Activation of this pore is thought to be involved in the induction of apoptotic and necrotic cell death.

NFKBIA belongs to the I-kappa-B family of proteins which is separated into four groups (IkB-a, IkB-b, IkB-g, IkB-e). NFKBIA inhibits the NFkB complex by binding and impounding it in the cytoplasm. When stimulated, NFKBIA is phosphorylated on serine residues targeting it for degradation by the ubiquitin pathway.

Complement Factor B, also known as CFB, encodes complement factor B which is a component of the alternative pathway of complement activation. Factor B circulates in the blood as a single chain polypeptide. Once the alternative pathway is activated it is cleaved by complement factor D yielding the noncatalytic chain Ba and the catalytic subunit Bb. The active subunit Bb is a serine protease which connects with C3b to form the alternative pathway C3 convertase. Also, Bb is involved in the proliferation of preactivated B lymphocytes, while Ba inhibits their proliferation.

PNMT is an enzyme located in the adrenal medulla and it catalyzes the final step of the catecholamine biosynthesis pathway. PNMT has beta-carboline 2N-methyltransferase activity. PNMT takes part in regulating epinephrine production. Glucocorticoid receptors form multimers of PNMT independent of the DNA binding domain. PNMT expression is regulated late in mouse gestation by AP2-alpha and glucocorticoids.

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/macrophage migration, 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 mitogenesis and 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 is linked to POEMS syndrome, also known as Crow-Fukase syndrome. Mutations in this gene have been associated with proliferative and nonproliferative diabetic retinopathy.

TBCEL, is a factor that is in charge of the microtubule cytoskeleton in determining cell behavior. TBCEL plays a role as a regulator of tubulin stability. While widely expressed in testis, TBCEL is also present in several tissues at a much lower level. TBCEL comprises of seven LRR (leucine-rich) repeats, one LRRCT domain and one ubiquitin-like domain. The gene that translates TBCEL consists of 66,704 bases and maps to human chromosome 11q23.3. Chromosome 11 houses over 1,400 genes and consist of nearly 4% of the human genome. Jervell and Lange-Nielsen syndrome, Jacobsen syndrome, Niemann-Pick disease, hereditary angioedema and Smith-Lemli-Opitz syndrome are associated with defects in genes that map to chromosome 11.

BLVRB (EC 1.3.1.24) catalyzes electron transfer from reduced pyridine nucleotides to flavins as well as methylene blue, pyrroloquinoline quinone, riboflavin, or methemoglobin. BLVRB is involved in protecting cells from oxidative damage or in regulating iron metabolism. BLVRB converts biliverdin to bilirubin in the liver, converting a double-bond between the second and third pyrrole ring into a single-bond. BLVRB plays a role as in human erythrocytic heme catabolic pathway and most mammalian species. Biliverdin reductase is abundantly expressed in kidney, spleen, liver and brain as well as at lower levels in the thymus and minimal levels being detected in testis.

GGCT is a member of the family of transferases, specifically the aminoacyltransferases. GGCT protein catalyzes the formation of 5-oxoproline from gamma-glutamyl dipeptides and takes an important part in glutathione homeostasis. GGCT induces release of cytochrome c from mitochondria with resultant induction of apoptosis.

Fibroblast growth factor 16 (FGF16) is a member of the large FGF family, whose members are heparin-binding growth factors with a core 120 amino acid (a.a.) FGF domain which allows for a common tertiary structure. Human FGF16 cDNA is a 207 aa precursor protein with one N-linked glycosylation site. FGF16 though lacking a typical signal peptide, is efficiently produced by mechanisms other than the classical protein secretion pathway. FGF16 is expressed in cardiac cells and is required for proper heart development. FGF16 gene mutation was also observed in individuals with metacarpal 4-5 fusion. FGF16 has an imperative role in the regulation of embryonic development, cell proliferation and cell differentiation, and is required for normal cardiomyocyte proliferation and heart development.

NUDT2 belongs to the MutT family of nucleotide pyrophosphatases, a subset of the larger NUDIX hydrolase family. NUDT2 conserves homeostasis by using water to cleave the metabolite NUDT symmetrically back into its original ATP and AMP molecules. In addition, NUDT2 is active towards other adenosine and diadenosine polyphosphates with four or more phosphate groups, however, not towards diadenosine triphosphate. NUDT2 has a role in heat shock and metabolic stress by regulating intracellular dinucleoside polyphosphate concentrations.

NUDT9 is a member of a superfamily of Nudix hydrolases. NUDT9 functions as a highly specific adenosine diphosphate ribose pyrophosphatase which hydrolyzes ADP ribose to AMP and ribose 5'-phosphate. In addition, NUDT9 may be involved in the regulation of the menstrual cycle and may be related to the proliferation of glandular cells in the human endometrium.

Arginase-1 is part of the urea cycle, it catalyzes the hydrolysis of arginine to ornithine and urea. There are two isoforms of mammalian arginase which differ in their tissue location, subcellular localization, immunologic crossreactivity & physiologic role. Arginase-1is a cytosolic enzyme and expressed primarily in the liver tissue. Inherited deficiency in this enzyme may lead toargininemia, which is an autosomal recessive disease in which hyperammonemia is detected.

WFDC12 belongs to the WFDC (WAP-type four-disulfide core) domain family. The WAP signature motif or WFDC domain has four disulfide bonds created by eight cysteines at the core of the protein, which operates as a protease inhibitor.

ALKBH2 is a member of the ALKB family.ALKBH2 is expressed in the heart, colon, liver, testis, ovary, prostate and the small intestine. ALKBH2 uses iron as a cofactor and acts as a dioxygenase which catalyzes the repair of alkylated DNA and RNA containing 1-methyladenine and 3-meth-ylcytosine. ALKBH2 is functionally activated by ascorbate and requires oxygen and ?-ketoglutarate for enzymatic activity.

EGF Domain-Specific O-Linked N-Acetylglucosamine Transferase (EOGT) takes part in the regulation of Notch receptor. EOGT catalyzes the transfer of a single N-acetylglucosamine from UDP-GlcNAc to a serine/ threonine residue in extracellular proteins resulting in their modification with a beta-linked N-acetylglucosamine (O-GlcNAc). EOGT mainly glycosylates the Thr residue positioned between the fifth and sixth conserved cysteines of folded EGF-like domains.

RRM2 catalyzes the formation of deoxyribonucleotides from ribonucleotides. Synthesis RRM2 is regulated in a cell-cycle dependent method. RRM2 supplies the precursors essential for DNA synthesis. RRM2 catalyzes the biosynthesis of deoxyribonucleotides from the corresponding ribonucleotides. RRM2 Inhibits Wnt signaling.

Arsenic Methyltransferase (AS3MT) catalyzes the transfer of a methyl group from S-adenosyl-L-methionine (AdoMet) to trivalent arsenical and may have a role in arsenic metabolism. AS3MT methylates arsenite to produce methylarsonate, Me-AsO3H2, which is reduced by methylarsonate reductase to methylarsonite, Me-As(OH)2. Methylarsonite which is also a substrate, is transformed into the much less toxic complex dimethylarsinate (cacodylate), Me2As(O)-OH.

D-amino-acid oxidase or DAAO is an enzyme that oxidizes D-amino acids to their imino acids form while using FAD (flavin adenine dinucleotide) as a co-factor, resulting in the formation of ammonia & hydrogen peroxide. the enzyme may take part in keeping the balance of acid base in the kidney tissue. Another role is to detoxifying molecules that abolish D-amino acids aggregated while the cell ages.