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Serum-and glucocorticoid-regulated kinase (SGK1) is a serine/threonine protein kinase and a member of the “AGC” subfamily, which includes protein kinases A, G, and C. The SGK1 protein has an imperative role in activating specific potassium, sodium and chloride channels, suggesting a participation in the regulation of processes such as cell survival, neuronal excitability, and renal sodium excretion. SGK1 is activated in vitro by PDK-1 (3-phosphoinositide-dependent protein kinase-1) and in vivo in reaction to signals which activate phosphatidylinositol (PI) 3-kinase.

Tribbles Pseudokinase 3, also known as TRIB3, is a putative protein kinase which is induced by the transcription factor NF-kappaB. In addition, TRIB3 is a negative regulator of NF-kappaB, and can as well sensitize cells to TNF- and TRAIL-induced apoptosis. Furthermore, TRIB3 is able to negatively regulate the cell survival serine-threonine kinase AKT1. One of the diseases which are associated with TRIB3 is anoxia.

cAMP-regulated phosphoprotein 19 (ARPP19) is protein phosphatase inhibitor which specifically inhibits protein phosphatase 2A (PP2A) during mitosis. When phosphorylated at Ser-62 during mitosis, ARPP19 specifically interacts with PPP2R2D (PR55-delta) and inhibits its activity, leading to inactivation of PP2A, a vital condition to maintain cyclin-B1-CDK1 activity high during M phase. ARPP19 protein may indirectly boost GAP-43 expression. The 19 kDa cAMP-regulated phosphoprotein has a role in regulating mitosis by obstructing protein phosphatase-2A.

Protein Phosphatase 1, Regulatory Subunit 3B (PPP1R3B) is the catalytic subunit of the serine/theonine phosphatase, protein phosphatase-1. PPP1R3B, which is expressed both in liver and in skeletal muscle tissue, regulates glycogen synthesis in these tissues. PPP1R3B is involved in type 2 diabetes and maturity-onset diabetes of the young.

PI3Ka plays a specific role in apoptosis in human colon cancer cells. Injection of neutralizing antibodies specific to PI3Ka into adenocarcinoma cells induced apoptosis, a response that was reverted by treating cells with caspase inhibitor. It was also shown that PI3Ka mediated phosphorylation of the p85a adapter reduces the lipid kinase activity of the heterodimer and this gives hints for PI3K-dependent signaling events not requiring production of 3’-phosphorylated phosphoinositides.
PI3Ka is a key regulator of the initiation of keratinocyte differentiation. A decrease in PI3Ka activity results in a loss of keratinocyte adhesion to the extracellular membrane and the initiation of early phase differentiation.

Protein Phosphatase 1, Regulatory Subunit 8 (PPP1R8) is the RNA-binding subunit of a key species of protein phosphatase-1 in the nucleus. The PPP1R8 enzyme is an inhibitor subunit of the main nuclear protein phosphatase-1 (PP-1). PPP1R8 has RNA-binding activity however it doesn’t cleave RNA and may target PP-1 to RNA-associated substrates. Two isoforms of the PPP1R8 protein are specific inhibitors of type 1 serine/threonine protein phosphatases which can bind but not cleave RNA. The third isoform of the PPP1R8 protein is deficient in of the phosphatase inhibitory activity nonetheless it is a single-strand endoribonuclease comparable to RNase E of E. coli.

KGF-2 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. FGF-10 exhibits mitogenic activity for keratinizing epidermal cells, but essentially no activity for fibroblasts, which is similar to the biological activity of FGF7. Studies of the mouse homolog of suggested that this gene is required for embryonic epidermal morphogenesis including brain development, lung morphogenesis, and initiation of lim bud formation. This gene is also implicated to be a primary factor in the process of wound healing.

The gene for TNFRSF12A was initially recognized as a fibroblast growth factor inducible immediate early response gene Fn14 in mouse NIH 3T3 fibroblasts. Human TNFRSF12A cDNA encodes a 129 amino acid residue type I transmembrane protein with a 27 aa signal peptide, a 53 aa extracellular domain, a 21 aa transmembrane domain and a 28 aa cytoplasmic domain. Human and mouse TNFRSF12A hold 82% aa sequence identity. TNFRSF12 is the tiniest member of the TNF receptor superfamily and has only one cysteine rich region in its extracellular domain. The TNFRSF12A cytoplasmic domain holds one TRAF binding motif which binds TRAFs 1, 2, and 3. TNFRSF12A binds its ligand TWEAK/TNFSF12A with high affinity to initiate a signal transduction cascade which subject to the cell type, causes different cellular responses such as cell death, cell proliferation, and angiogenesis.

Ring Finger & CHY Zinc Finger Domain Containing 1 (RCHY1) acts as an ubiquitin ligase. RCHY1 mediates E3-dependent ubiquitination and proteasomal degradation of target proteins which among them are TP53, HDAC1 and CDKN1B, consequently regulating their levels and cell cycle progression. RCHY1 is also increases AR transcription factor activity.

ASB13 belongs to the ankyrin repeat and SOCS box-containing (ASB) family of proteins which contains ankyrin repeat sequence and a SOCS box domain. ASB13 is a protein coding gene that plays a role as a substrate-recognition part of a SCF-like ECS E3 ubiquitin-protein ligase complex which arbitrates the ubiquitination and subsequent proteasomal degradation of target proteins.

PPP3CA (aka Calcineurin A) is a major soluble calmodulin binding protein in the brain and a Ca2+/calmodulin dependent serine/threonine protein phosphatase, with a relatively limited substrate specificity. PPP3CA activates the T cells of the immune system and can be blocked by drugs. PPP3CA activates NFATc (a transcription factor) by dephosphorylating it. The activated NFATc is subsequently translocated into the nucleus, where it upregulates the expression of interleukin 2.

PPP1R14A is a phosphorylation-dependent inhibitor of smooth muscle myosin phosphatase. Inhibition of PPP1R14A results to increased myosin phosphorylation and enhances smooth muscle contraction in the absence of increased intracellular Ca(2+) concentration. Myosin phosphatase can reverse MYL (myosin light chain) phosphorylation to induce a state of relaxation. However, during agonist-induced contraction at constant Ca2+ concurrent inhibition of myosin phosphatase leads to increases in MYL phosphorylation and tension. These calcium-independent increases in myosin phosphorylation and tension are termed calcium sensitization.
Human pregnancy is characterized by the increases of PKN1 expression and CPI-17 phosphorylation in the myometrium. PPP1R14A is mapped to chromosome 19q13.13-q13.2.
PPP1R14A binds directly to protein kinase C and casein kinase I.
PPP1R14A siRNA decreased the level of merlin phosphorylation and consequently Ras and ERK activity in human tumor cell lines.
PKC/CPI-17 mediated pathway in histamine, triggeres cytoskeletal rearrangements causing lung microvascular barrier compromise.

FGF-1 Intracellular-Binding Protein (FIBP) which is a member of Fibroblast growth factors (FGFs) binds to internalized FGF-1 and is thought to be involved in mitogenic function of FGF-1. FGF activity effects development, adult tissue homeostasis, angiogenesis and cancer progression. FIBP localizes to the nucleus and is greatly expressed in heart, skeletal muscle and pancreas and at lower levels in brain, placenta, liver and kidney.

PC4 and SFRS1 Interacting Protein 1 (PSIP1) is a transcriptional coactivator involved in neuroepithelial stem cell differentiation and neurogenesis. PSIP1 is also involved particularly in lens epithelial cell gene regulation and stress responses. PSIP1 has a significant role in lens epithelial to fiber cell terminal differentiation. In addition, PSIP1 plays a protective role during stress-induced apoptosis. Furthermore, PSIP1 is a cellular cofactor for lentiviral integration.

KGF 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. FGF7 is a potent epithelial cell-specific growth factor, whose mitogenic activity is predominantly exhibited in keratinocytes but not in fibroblasts and endothelial cells. Studies of mouse and rat homologs of this gene implicated roles in morphogenesis of epithelium, reepithelialization of wounds, hair development and early lung organogenesis.

PPP3R1 is a Ser/Thr-specific calcium and calmodulin-dependent protein phosphatase which takes a vital part in the T cell activation pathway. Calcineurin is composed of two subunits; calcineurin A (CnA) and calcineurin B (CnB). Dephosphorylation of the nuclear factor of activated T-cells (NF-AT) by Calcineurin is essential for NF-AT activation, nuclear translocation, and early gene expression in T-cells.

SH3 domain-binding glutamic acid-rich-like protein 3 (SH3BGRL3) which is located on chromosome 1p34.3-35, encodes for a small 93 amino acids protein. SH3BGRL3 is the newest member of thioredoxin super family, whose posttranslational altered form was recognized as TNF-alpha inhibitory protein. SH3BGRL3 may act as a regulator in all-trans retinoic acid-induced pathway and also as a modulator of glutaredoxin biological activity.

GLRX1 has a glutathione-disulfide oxidoreductase activity in the presence of nadph and glutathione reductase. reduces low molecular weight disulfides and proteins. Glutaredoxin is a glutathione (GSH)-dependent hydrogen donor for ribonucleotide reductase and also catalyzes glutathione-disulfide oxidoreduction reactions in the presence of NADPH and glutathione reductase. GLRX1 is multifunctional enzyme with glutathione-dependent oxidoreductase, glutathione peroxidase and glutathione S-transferase (GST) activity. The disulfide bond functions as an electron carrier in the glutathione-dependent synthesis of deoxyribonucleotides by the enzyme ribonucleotide reductase. In addition, it is also involved in reducing cytosolic protein- and non-protein-disulfides in a coupled system with glutathione reductase. Required for resistance to reactive oxygen species (ROS) by directly reducing hydroperoxides and for the detoxification of ROS-mediated damage.

ANXA2 is part of the annexin family and is involved in the regulation of cellular growth and in signal transduction pathways. ANXA2 protein functions as an autocrine factor which increases osteoclast formation and bone resorption. ANXA2 is associated with sickle cell osteonecrosis. Reduced ANXA2 expression is associated with osteosarcoma metastases. ANXA2 is part of the putative cell surface vitamin D binding protein binding site complex and functions to mediate the chemotactic cofactor effect. ANXA2 is involved in dysferlin deficiency and in muscular dystrophies. Human colon adenocarcinoma cell differentiation is related with an up-regulation of ANXA2.

GNAI2 is an alpha subunit of guanine nucleotide binding proteins (G proteins) and holds a guanine nucleotide binding site. GNAI2 takes part in the hormonal regulation of adenylate cyclase. GNAI2 has varies transcript variants encoding different isoforms yet only two full-length isoforms were identified up to date.

Serine/threonine-protein kinase 3 (), is a mammalian Ste20-related protein kinases most closely related to Drosophila Hippo, which is a major regulator of cell proliferation as well as survival in the course of development. STK3 is a serine/threonine kinase which functions early in a pheromone responsive signal transduction cascade in yeast. Furthermore, STK3 activates the human large tumor suppressor kinase Lats1. STK3 also modulates stress-induced cardiac hypertrophy.

DUSP23 is a member of the protein-tyrosine phosphatase family. DUSP23 is a protein phosphatase which facilitates dephosphorylation of phosphorylated proteins on Tyr and Ser/Thr residues. In vitro, DUSP23 dephosphorylate p44-ERK1 (MAPK3) but not p54 SAPK-beta (MAPK10). In addition, DUSP23 enhances activation of JNK and p38(MAPK14).

Cyclin-dependent kinase inhibitor 3 (CDKN3) is a member of the dual specificity protein phosphatase family. CDKN3 was identified as a cyclin-dependent kinase inhibitor, and was shown to interact with, and dephosphorylate CDK2 kinase, consequently prevent the activation of CDK2 kinase. In addition CDKN3 is important in cell cycle regulation. The CDKN3 gene was reported to be deleted, mutated, or overexpressed in several kinds of cancers.