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Janus Kinase 2 (JAK2) is a protein tyrosine kinase which takes part in a specific subset of cytokine receptor signaling pathways such as cell growth, development, differentiation or histone modifications. JAK2 is linked with the prolactin receptor and is necessary for responses to gamma interferon. Mice which do not express an active protein for JAK2 show embryonic lethality associated with the absence of definitive erythropoiesis.

Thymidylate kinase (DTYMK) is involved in pyrimidine metabolism. Specifically, DTYMK catalyzes the ATP-dependent conversion of dTMP (deoxythymidine monophosphate) to dTDP (deoxythymidine diphosphate), which then acts as one of the 4 nucleotides in DNA. Through its role in the catalytic creation of dTDP, DTYMK has an imperative role in the pathway of DNA synthesis and is assumed to be involved in cell cycle progression and cell growth.

TIE-1 (tyrosine kinase with Ig and EGF homology domains 1) and TIE-2/Tek comprise a receptor tyrosine kinase (RTK) subfamily with unique structural characteristics: two immunoglobulin-like domains flanking three epidermal growth factor (EGF)-like domains and followed by three fibronectin type III-like repeats in the extracellular region and a split tyrosine kinase domain in the cytoplasmic region. These receptors are expressed primarily on endothelial and hematopoietic progenitor cells and play critical roles in angiogenesis, vasculogenesis and hematopoiesis. Human TIE-1 cDNA encodes a 1124 amino acid (aa) residue precursor protein with an 18 residue putative signal peptide, a 727 residue extracellular domain and a 354 residue cytoplasmic domain. Whereas two ligands have been described for TIE-2 [angiopoietin-1 (Ang1) and angiopoietin-2 (Ang2)], so far no ligand was found for TIE-1.

PTP4A2 is part of a small class of the protein tyrosine phosphatase (PTP) family. PTP4A2 is localized to the early endosome that take part in a variety of cellular activities. PTP4A2 protein interacts with the beta-subunit of Rab geranylgeranyltransferase II (beta GGT II), therefore has a role as a regulator of GGT II activity. Overexpression of PTP4A2 in mammalian cells conferred a transformed phenotype, which suggested its role in tumorigenesis.

Testis-specific serine/threonine-protein kinase 6 (TSSK6) is an intronless gene, which belongs to the CAMK Ser/Thr protein kinase family. The TSSK6 protein contains one protein kinase domain. TSSK6 is highly expressed in the testis and lowly expressed in the colon, prostate, thymus, small intestine, and peripheral blood leukocytes. TSSK6 interacts with the heatshock proteins HSPA8, HSPCB, and HAPA1A; these interactions seem to be essential for TSSK6 kinase activity. TSSK6 plays a role in DNA condensation during postmeiotic chromatin remodeling. In addition, TSSK6 is required for sperm production and function.

Thiamin pyrophosphokinase 1 (TPK1) is a homodimer which catalyzes the phosphorylation of thiamine to thiamine pyrophosphate. TPK1 is found in the heart, kidney, testis, small intestine and peripheral blood leukocytes, and at very low levels in a variety of tissues. TPK1 gene defects cause the thiamine metabolism dysfunction syndrome type 5, episodic encephalopathy type (THMD5), which is an autosomal recessive metabolic disorder due to an inborn error of thiamine metabolism.

TIE-1 (tyrosine kinase with Ig and EGF homology domains 1) and TIE-2/Tek comprise a receptor tyrosine kinase (RTK) subfamily with unique structural characteristics: two immunoglobulin-like domains flanking three epidermal growth factor (EGF)-like domains and followed by three fibronectin type III-like repeats in the extracellular region and a split tyrosine kinase domain in the cytoplasmic region. These receptors are expressed primarily on endothelial and hematopoietic progenitor cells and play critical roles in angiogenesis, vasculogenesis and hematopoiesis. Human TIE-1 cDNA encodes a 1122 amino acid (aa) residue precursor protein with an 18 residue putative signal peptide, a 726 residue extracellular domain and a 353 residue cytoplasmic domain. Two ligands, angiopoietin-1 (Ang1) and angiopoietin-2 (Ang2), which bind TIE-2 with high-affinity have been identified. Ang2 has been reported to act as an antagonist for Ang1. Mice engineered to overexpress Ang2 or to lack Ang1 or Tie-1 display similar angiogenic defects.

Tyrosine 3-monooxygenase (Th), is a rate-limiting enzyme in catecholamine synthesis. Th utilizes tetrahydrobiopterin as well as molecular oxygen to convert tyrosine to DOPA. Th regulates dopamine (DA) neurotransmission at the biosynthesis and reuptake steps. Th takes a vital part in the physiology of adrenergic neurons. Furthermore, Th effects overexpression in lymphocytes on the differentiation as well as function of T helper cells.

Hydroxylysine Kinase, also known as HYKK, is a Protein Coding gene. HYKK which is a part of the aminoglycoside phosphotransferase family catalyzes the GTPdependent phosphorylation of 5-hydroxy-L-lysine.

The 14-3-3 family of proteins plays a key regulatory role in signal transduction, checkpoint control, apoptotic and nutrient-sensing pathways. 14-3-3 proteins are highly conserved and ubiquitously expressed. There are at least seven isoforms that have been identified in mammals. The 14-3-3gamma, a subtype of the 14-3-3 family of proteins, was thought to be brain and neuron-specific. It has been shown to interact with RAF1 and protein kinase C, proteins involved in various signal transduction pathways.

Adenosine Kinase is an abundant enzyme in mammalian tissues which catalyzes the transfer of the gamma-phosphate from ATP to adenosine, thus is as a regulator of concentrations of both extracellular adenosine and intracellular adenine nucleotides. Adenosine has extensive effects on the cardiovascular, nervous, respiratory, and immune systems and inhibitors of the enzyme take a crucial pharmacological part in growing intravascular adenosine concentrations and acting as anti-inflammatory agents.

PINK1 is a serine/threonine protein kinase which is found in the mitochondria. PINK1 shields cells from stress-induced mitochondrial dysfunction. Mutations results in one form of autosomal recessive early-onset Parkinson disease.

Astyrosine-protein phosphatase non-receptor type 11 isoform 2 (PTPN11), is a member of the protein-tyrosine phosphatase family, non-receptor class 2 subfamily. PTPN11 takes part in signal transduction from the cell surface to the nucleus downstream of various cytosolic protein tyrosine kinases as well as receptors. PTPN11 deficient cells have poor mobility due to excessive phosphorylation of FAK as well as other proteins which interfere with the rotation of cell attachment points in the focal adhesion complex.

Inositol-tetrakisphosphate 1-kinase (ITPK1) is a 414 amino acid monomer which is a member of the ITPK1 family and exists as 2 alternatively spliced isoforms. ITPK1 highest levels are found in the brain, followed by the heart, skeletal muscle, kidney, pancreas, liver, placenta and lung. ITPK1 is comprised of one ATP-grasp domain and has been shown to phosphorylate various inositol polyphosphates and modify TNFa induced apoptosis.

MAPK14 belongs to the MAP kinase family and is most associated with p38 MAP kinases(MAPKs). MAPKs are activated mainly as a reaction to cellular stress and inflammatory cytokines, and inhibitors that target the MAPK14 and MAPK11 have demonstrated ability to cure inflammatory disease. The substrates of this kinase contain transcription regulator ATF2, MEF2C, and MAX, cell cycle regulator CDC25B, and tumor suppressor p53, which demonstrate the parts of MAPK14 in stress-related transcription, cell cycle regulation and genotoxic stress response.

Mitogen-activated protein kinase 1 (MAPK1) is also known as "extracellular signal-regulated kinase 2" (ERK2). Two similar (85% sequence identity) protein kinases were originally called ERK1 and ERK2. They were found during a search for protein kinases that are rapidly phosphorylated after activation of cell surface tyrosine kinasessuch as the epidermal growth factor receptor. Phosphorylation of ERKs leads to the activation of their kinase activity.
The molecular events linking cell surface receptors to activation of ERKs are complex. It was found that RasGTP-binding proteins are involved in the activation of ERKs. Another protein kinase, Raf-1, was shown to phosphorylate a "MAPK kinase", thus qualifying as a "MAPK kinase kinase". The MAPK kinase was named "MAPK/ERK kinase" (MEK).
Receptor-linked tyrosine kinases, Ras, Raf, MEK and MAPK could be fitted into a signaling cascade linking an extracellular signal to MAPK activation.
Transgenic gene knockoutmice lacking MAPK1 have major defects in early development.

PKLR is a pyruvate kinase which catalyzes the transphosphorylation of phohsphoenolpyruvate into pyruvate and ATP. That is the rate-limiting step of glycolysis. PKLR gene encodes the L- and R-type isoenzymes through alternate splicing events controlled by different promoters. L-type isoform can also appear as a tetramer and is upregulated by glucose with implications in maturity-onset diabetes of the young.

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.

CAMK4 is a member of the serine/threonine protein kinase family, and of the Ca(2+)/calmodulin-dependent protein kinase subfamily. CAMK4 is a multifunctional serine/threonine protein kinase with restricted tissue distribution which is associated to transcriptional regulation in lymphocytes, neurons and male germ cells.

TIE-1 (tyrosine kinase with Ig and EGF homology domains 1) and TIE-2/Tek comprise a receptor tyrosine kinase (RTK) subfamily with unique structural characteristics: two immunoglobulin-like domains flanking three epidermal growth factor (EGF)-like domains and followed by three fibronectin type III-like repeats in the extracellular region and a split tyrosine kinase domain in the cytoplasmic region. These receptors are expressed primarily on endothelial and hematopoietic progenitor cells and play critical roles in angiogenesis, vasculogenesis and hematopoiesis. Human TIE-1 cDNA encodes a 1124 amino acid (aa) residue precursor protein with an 18 residue putative signal peptide, a 727 residue extracellular domain and a 354 residue cytoplasmic domain. Whereas two ligands have been described for TIE-2 [angiopoietin-1 (Ang1) and angiopoietin-2 (Ang2)], so far no ligand was found for TIE-1.

Tyrosyl-tRNA synthetase (YARS2) is a mitochondrial protein which catalyzes the attachment of tyrosine to tRNA(Tyr) in a two-step reaction: tyrosine is first activated by ATP to form Tyr-AMP and afterward transferred to the acceptor end of tRNA(Tyr). YARS2 gene mutations are linked with myopathy with lactic acidosis and sideroblastic anemia type 2 (MLASA2).

CDK16 is a member of the CDK family of serine/threonine protein kinases which are known to regulate the cell cycle. These proteins have a core kinase domain flanked by unique amino- and carboxy- terminal domains. CDK16, which is expressed mainly in mammalian brain, cooperates with an assortment of proteins, and is a part of a multiple signal transduction cascade.

Protein Tyrosine Phosphatase 1B is the founding member of the protein tyrosine phosphatase (PTP) family, which was isolated and identified based on its enzymatic activity and amino acid sequence. PTPs catalyze the hydrolysis of the phosphate monoesters specifically on tyrosine residues. Members of the PTP family share a highly conserved catalytic motif, which is essential for the catalytic activity. PTPs are known to be signaling molecules that regulate a variety of cellular processes including cell growth, differentiation, mitotic cycle, and oncogenic transformation. This PTP has been shown to act as a negative regulator of INS signaling by dephosphorylating the phosphotryosine residues of INS receptor kinase. This PTP was also reported to dephosphorylate epidermal growth factor receptor kinase, as well as JAK2 and TYK2 kinases, which implicated the role of this PTP in cell growth control, and cell response to IFN stimulation.

Extracellular signal-regulated kinases (ERKs) or classical MAP kinases are widely expressed protein kinaseintracellular signalingmolecules which are involved in functions including the regulation of meiosis, mitosis, and postmitotic functions in differentiated cells. Many different stimuli, including growth factors, cytokines, virusinfection, ligands for heterotrimeric G protein-coupled receptors, transforming agents, and carcinogens, activate the ERK pathway.
The term, "extracellular signal-regulated kinases", is sometimes used as a synonym for mitogen-activated protein kinase(MAPK), but has more recently been adopted for a specific subset of the mammalianMAPK family. In the MAPK/ERK pathway, Rasactivates c-Raf, followed by MEKand then MAPK1/2 (below). Ras is typically activated by growth hormones through receptor tyrosine kinasesand GRB2/SOS, but may also receive other signals. ERKs are known to activate many transcription factors and some downstream protein kinases. Disruption of the ERK pathway is common in cancers, especially Ras, c-Raf and receptors such as HER2.Mitogen-activated protein kinase 3 (MAPK3) is also known as "extracellular signal-regulated kinase 1" (ERK1). Transgenic gene knockoutmice lacking MAPK3 are viable and it is thought that MAPK1 can fulfill most MAPK3 functions in most cells. The main exception is in T cells. Mice lacking MAPK3 have reduced T cell development past the CD4+CD8+ stage.