PDGF family has a lot of members and the latelet-derived growth factor (PDGFs) is a powerful mitotic and chemotactic protein necessary for early development and wound healing. In addition, they may play a pathological role in tumor growth, vascular disease and fibrous disease. Four genes are known to encode PDGF proteins, PDGF-A, PDGF-B, PDGF-C and PDGF-D. PDGFs is produced by a discrete cell population and is secreted in the form of disulfide bonds linked to dimer or heterodimer including PDGF-AA, PDGF-BB, PDGF-CC, PDGF-DD and PDGF-AB. PDGF dimers bind to PDGF receptors in a major paracrine manner. Two known PDGF receptors, PDGF R α and PDGF R β, can form both heterodimer and homologous dimer. Ligand binding promotes receptor dimerization, self-phosphorylation, activates multiple downstream intracellular signal cascades, stimulates actin rearrangement and destroys. Gap junctions communicate to initiate gene transcription and cell survival.

As for the EGF family, it could be easier. The system provides a variety of tools for epidermal growth factor (EGF) family members and their EGF R/ErbB receptors. These include highly specific EGF family antibodies, proteins, and ELISAs. Members of the EGF family are best known for their ability to stimulate cell growth and proliferation and are important for many developmental processes, including the promotion of mitosis and differentiation. Proliferation of mesenchymal and epithelial cells. EGF family members have at least one common structural motif and the EGF domain which consists of six conserved cysteine residues and forms three disulfide bonds. Most of them were synthesized in the form of membrane associated with protein cleavage before liberation. Their family members are including EGF, NeuRegins, AmphiRegin, Betacellulin and others. EGF-F active hermaphroditic members are mediated by EGF R/ErbB receptor tyrosine kinase. When not regulated, members of the family and their receptors are known to be involved in tumor formation.

And the FGF family also known as Fibroblast growth factor (FGFs) is involved in apoptosis, cell survival, chemotaxis, cell adhesion, migration, differentiation and proliferation. FGFs consists of 22 genes encoding structure-related proteins. FGFs mediates cellular responses by binding to De and activating four receptor tyrosine kinase (RTK) families. High affinity was expressed with fibroblast growth factor receptor FGFR 1-FGFR 4.

The most common pathway of FGFs is the mitogen-activated protein kinase (MAPK) pathway. It is related to lipid anchored docking protein fibroblast growth factor receptor substrate 2 (FRS 2). FGFR 1 FGFR2 and FGFR 3, but not FGFR 4. FRS2 tyrosine phosphorylation sites are recognized and bound by the adapter protein Growth factor receptor-bound protein 2 (GRB2) and the protein tyrosine phosphatase (PTP) Tyrosine phosphatase non-receptor type 11 (SHP-2) , as an adapter protein. FGFR1, FGFR3, FGFR4 can phosphorylate Shc transforming protein directly. Shc and GRB2 form a complex with the guanine nucleotide exchange factor Son of sevenless (SOS) via its SH3 domain. By binding to the plasma membrane of phosphorylated FRS 2, this complex enables SOS to activate the oncogene homology (H-Ras) of Harvey sarcoma virus via gtp exchange. It is insensitive to membrane bound H-RAS. Once in the active gtp binding state, H-Ras interacts with multiple effector proteins, thereby activating the (Erk) signal transduction of mtg activated protein kinases into ca.. Scudder. This cascade leads to cell proliferation.

Assembly of FRS2/ GRB2/ GRB2-associated binding protein 1 (GAB1) complex is induced by FGF stimulation that results in activation of Phosphatidylinositol-3 kinase (PI3K) and downstream effector proteins, such as V-akt murine thymoma viral oncogene homolog 1 (AKT(PKB)), whose cellular localization and activity are regulated by products of PI3K, Phosphatidylinositol 3,4,5-triphosphate (PtdIns (3,4,5) P3).

FGF plays a critical role in membrane phospholipid hydrolysis in the cell. Upon binding to FGFR1, FGFR3, FGFR4, FGFs stimulates cytosolic form of Phospholipase C-gamma1 (PLC-gamma 1). PLC-gamma activation by FGFleads to Phosphatidylinositol 4,5-biphosphate (PtdIns(4,5)P2 ) hydrolysis and generation of two second messengers, Diacylglycerol ( DAG ) and IP3. IP3activates IP3 receptor (IP3 receptor) and accumulation of Ca 2+ in the cytoplasm. DAG activates Protein kinase C delta (PKC-delta).