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HER-2/neu (erbB-2) encodes an 185-kDa orphan receptor tyrosine kinase that is constitutively active as a dimer and displays potent oncogenic activity when overexpressed. Herstatin, as the product of alternative HER-2 transcript, retains intron 8.
The herstatin mRNA is expressed in normal human fetal kidney and liver, but is at reduced levels relative to p185HER-2 mRNA in carcinoma cells that contain an amplified HER-2 gene. Herstatin appears to be an inhibitor of p185HER-2, because it disrupts dimers, reduces tyrosine phosphorylation of p185, and inhibits the anchorage-independent growth of transformed cells that overexpress HER-2.

ROBLD3 is a member of the GAMAD family. ROBLD3 is an adapter protein which enhances the efficiency of the MAP kinase cascade and facilitates the activation of MAPK2. ROBLD3 compels the recruitment of MP1 to late endosomes where they form a very stable heterodimeric complex required for ERK activation on endosomes. In humans, a mutation in the ROBLD3 gene has been associated with a primary immunodeficiency syndrome, and suggests a role for the ROBLD3 protein in endosomal biogenesis.

Twinfilin (TWF1) is a ubiquitous actin-monomer-binding protein which is composed of two ADF-homology domains. Twinfilin forms a 1:1 complex with ADP-actin-monomers, prevents nucleotide exchange on actin monomers and blocks assembly of the monomer into filaments. TWF1 is composed of 2 ADF/cofilin-like (ADF-H) domains joined by a short linker region and followed by a C-terminal tail of approximately 20 residues. The 2 ADF-H domains are approximately 20% homologous to ADF/cofilin and to each other. TWF1 protein may be an actin monomer-binding protein, and its localization to cortical G-actin-rich structures might be regulated by the small GTPase RAC1.

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.

Adiponectin is a hormone exclusively expressed from adipose tissue. Many studies demonstrate that adiponectin has direct anti-diabetic, anti-atherogenic and anti-inflammatory functions. APM-1 can increase insulin sensitivity of skeletal muscle, attenuate hepatic lipogenesis and luconeogenesis, regulate NO production in endothelial cells, inhibit proliferation of smooth muscle cells and prevent lipid accumulation of macrophage cells.
In the circulation, adiponectin is present as three different oligomeric complexes, including the high molecular weight (HMW), the middle molecular weight (MMW, also called hexamer) and low molecular weigh (MMW, also called trimer) forms 8. Different oligomeric complex of adiponectin activates different signaling pathways and exerts distinct functions.

DUSPs are distinguished by their ability to dephosphorylate both tyrosine and serine/threonine residues. DUSPs have been implicated as major modulators of critical signaling pathways. Dual specificity phosphatase 19 (DUSP19) belongs to the dual specificity protein phosphatase subfamily. DUSP19 is a protein phosphatase which functions as a stress-activated protein kinase pathway-regulating phosphatase. DUSP19 contains a variation of the consensus DUSP C-terminal catalytic domain, with the last serine residue replaced by alanine, and lacks the N-terminal CH2 domain found in the MKP class of DUSPs.

Docking Protein 4(DOK4) is a member of the DOK family. DOK proteins are enzymatically inert adaptor or scaffolding proteins. The DOK proteins present a docking platform for the compilation of multimolecular signaling complexes. DOK4 serves in RET-mediated neurite outgrowth and has a positive role in activation of the MAP kinase pathway. DOK4 is a putative link with downstream effectors of RET in neuronal differentiation. DOK4 is involved in the regulation of the immune response induced by T-cells.

YWHAB belongs to the 14-3-3 family of proteins which are in charge for signal transduction by binding to phosphoserine-containing proteins. YWHAB is found in both plants and mammals. YWHAB protein interacts with RAF1 and CDC25 phosphatases,thus linking mitogenic signaling and the cell cycle machinery. YWHAB is an adapter protein involved in the regulation of a large spectrum of both general and specialized signaling pathway. YWHAB binds to a large number of proteins by recognition of a phosphoserine or phosphothreonine motif. Binding generally results in the modulation of the activity of the binding partner.

Regulation Of Nuclear Pre-MRNA Domain Containing 1A (RPRD1A) is upregulated in cells overexpressing cyclin-dependent kinase inhibitor p15(INK4b) and may have a part in cell cycle regulation. RPRD1A interacts with phosphorylated C-terminal heptapeptide repeat domain (CTD) of the largest RNA polymerase II subunit POLR2A, and partakes in dephosphorylation of the CTD. RPRD1A May function as a negative regulator of cyclin-D1 (CCND1) and cyclin-E (CCNE1) in the cell cycle.

Endothelial cells express three different vascular endothelial growth factor (VEGF) receptors, belonging to the family of receptor tyrosine kinases (RTKs). They are named VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1), VEGFR-3 (Flt-4). Their expression is almost exclusively restricted to endothelial cells, but VEGFR-1 can also be found on monocytes, dendritic cells and on trophoblast cells. The flt-1 gene was first described in 1990. The receptor contains seven immunoglobulin-like extracellular domains, a single transmembrane region and an intracellular splited tyrosine kinase domain. Compared to VEGFR-2 the Flt-1 receptor has a higher affinity for VEGF but a weaker signaling activity. VEGFR-1 thus leads not to proliferation of endothelial cells, but mediates signals for differentiation. Interestingly a naturally occuring soluble variant of VEGFR-1 (sVEGFR-1) was found in HUVE supernatants in 1996, which is generated by alternative splicing of the flt-1 mRNA. The biological functions of sVEGFR-1 still are not clear, but it seems to be an endogenous regulator of angiogenesis, binding VEGF with the same affinity as the full-length receptor.

Interleukin-1 beta is a cytokine that causes inflammation and can regulate angiogenesis through interaction with vascular endothelial cells or promoting the creation of proangiogenic modulators through the paracrine system. The cytokine causes migration and proliferation of endothelial cells, creation of mediators to inflammation, expression of adhesion-molecules & recruit of leukocyte cells. Interleukin-1 beta was found crucial for the process of tumors in various organism models.

CIB2 is a member of the calcium and integrin-binding family.CIB2 is possibly a Ca2+-binding regulatory protein which interacts with DNA-dependent protein kinase catalytic subunit (DNA-PKcs). In the skeletal muscle, CIB2 co-localizes with the integrin alpha7B subunit at the sarcolemma and at the neuromuscular and myotendinous junctions. CIB2 is closely related to CIB1.

HGF, also known as scatter factor (SF) and Hepatocyte growth factor, is secreted from mesenchymal cells, targets and acts mainly on epithelial and endothelial cells. The protein is a paracrine cellular growth, motility and morphogenic factor. HGF can also be part of haemopoietic progenitor cells and T cells. HGF has a crucial role in embryonic organ development, mainly in myogenesis. In adults HGF takes part in organ regeneration and wound healing.

LAMTOR2 is a member of the GAMAD family. LAMTOR2 is highly conserved with a mouse protein linked with the cytoplasmic face of late endosomes and lysosomes. The mouse protein interacts with MAPK scaffold protein 1, which is a component of the mitogen-activated protein kinase pathway. LAMTOR2 gene mutation has been associated with a primary immunodeficiency syndrome in humans, proposing a role for this protein in endosomal biogenesis.

Endothelial cells express three different vascular endothelial growth factor (VEGF) receptors, belonging to the family of receptor tyrosine kinases (RTKs). They are named VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1), VEGFR-3 (Flt-4). Their expression is almost exclusively restricted to endothelial cells, but VEGFR-1 can also be found on monocytes, dendritic cells and on trophoblast cells. The flt-1 gene was first described in 1990. The receptor contains seven immunoglobulin-like extracellular domains, a single transmembrane region and an intracellular splited tyrosine kinase domain. Compared to VEGFR-2 the Flt-1 receptor has a higher affinity for VEGF but a weaker signaling activity. VEGFR-1 thus leads not to proliferation of endothelial cells, but mediates signals for differentiation. Interestingly a naturally occuring soluble variant of VEGFR-1 (sVEGFR-1) was found in HUVE supernatants in 1996, which is generated by alternative splicing of the flt-1 mRNA. The biological functions of sVEGFR-1 still are not clear, but it seems to be an endogenous regulator of angiogenesis, binding VEGF with the same affinity as the full-length receptor.

All three VEGF receptors belong to the class III subfamily of receptor tyrosine kinases (RTKs) characterised by the seven immunoglobulin-like loops in the extracellular domain. The expression of VEGFR-1 to -3 is almost exclusively restricted to hematopoietic precursor cells, vascular and lymphatic endothelial cells and to the monocyte/macrophage lineage. They play key roles in vasculogenesis, hematopoiesis, angiogenesis and lymphangiogenesis. The FLT-4 cDNA encodes a 1298 amino acid (aa) residue precursor protein with a 23 aa residue signal peptide. Mature VEGFR-3/FLT-4 is composed of a 751 aa residue extracellular domain, a 22 aa transmembrane domain and a 482 aa residue cytoplasmic domain. Both VEGF family members VEGF-C and VEGF-D have been shown to bind and activate VEGFR-3/FLT-4. The Flt-4 gene is widely expressed in the early embryo but becomes restricted to the lymphatic endothelial a latter stages of development. It is important for lymphangiogenesis.

Calmodulin-2 acts as an intracellular calcium sensor protein. When the intracellular Ca2+ concentration increases, calmodulin can bind up to four Ca2+, changing its conformation and regulating cellular functions such as activation or inhibition of a large number of enzymes, ion channels, and receptors. P53 protein stimulates CALM2 gene expression in 041 cells. CALM-2 is involved in the processes of Ca(2+)-induced neuronal cell death and the blockage of calmodulin attenuates brain injury after cerebral ischemia. Calmodulin-2 mediates the control of a large number of enzymes and other proteins by ca(2+). among the enzymes to be stimulated by the calmodulin-ca(2+) complex are a number of protein kinases and phosphatases.

EPH Receptor A4 (Epha4), is a single-pass type 1 membrane protein which is a part of the protein kinase superfamily and ephrin receptor subfamily. Epha4 is a receptor tyrosine kinase which binds membrane-bound ephrin family ligands residing on adjacent cells, leading to contact-dependent bidirectional signaling into neighboring cells mainly in the nervous system and in erythropoiesis.

HSPB8 displays temperature-dependent chaperone activity. HSPB8 acts as a mn(2+)-dependent serine-threonine- specific protein kinase. we are not convinced that this is its true role. Defects in HSPB8 are a cause of distal hereditary motor neuropathy type ii (DHMN2) also known as distal spinal muscular atrophy (DSMA) and spinal muscular atrophy of the charcot-marie-tooth type. it is an autosomal dominant disorder of lower motor neurons characterized by distal muscle weakness.

PIM2 is a serine/threonine protein kinase which is a part of the CAMK family. PIM2 is expressed in various tissues mainly in spleen, thymus, testis and small intestine. PIM2 is implicated in tumor phenotypes and participates in the formation and preservation of Long-Term Potentiation (LTP). PIM2 is also involved in the positive regulation of chondrocyte survival and autophagy in the epiphyseal growth plate.

p59-Fyn is a member of the protein-tyrosine kinase oncogene family. p59fyn is a membrane-associated non-receptor protein tyrosine kinase that belongs to the Src-family of kinases. p59-Fyn encodes a membrane-associated tyrosine kinase which is implicated in the control of cell growth. p59-Fyn associates with the p85 subunit of phosphatidylinositol 3-kinase and interacts with the fyn-binding protein. The unique N-terminal domain of p59fyn interacts with the CD3 and eta chains of the TcR. p59fyn can bind other proteins (p82 and p116) through its SH2 and SH3 domains, which may act as substrates or regulators of fyn activity. p59fyn is highly expressed in brain suggesting that it may have a role in the sensory nervous network and in myelination at early stages of CNS formation. Distinct isoforms exist due to alternative splicing.