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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.

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.

PGK1 is an X-linked enzyme that has a major role in the glycolytic pathway. PGK1 is a glycolytic enzyme which catalyzes the conversion of 1,3-diphosphoglycerate to 3-phosphoglycerate, generating an ATP molecule. PGK1 may also act as a cofactor for polymerase alpha. Defects in the PGK1 gene are usually associated with chronic hemolytic anemia, though it can be accompanied by either mental retardation or muscular disease (rhabdomyolysis). Overexpression of PGK1 and its signalling targets are possibly an expression-pathway in diffuse primary gastric carcinomas promoting peritoneal dissemination. It was shown that PGK1 is differentially expressed in the dorsolateral prefrontal cortex from patients with schizophrenia.

PDXK converts vitamin B6 to Pyridoxal-5-phosphate (PLP), which is a vital cofactor in the intermediate metabolism of amino acids and neurotransmitters. PDXK is cytoplasmic and probably acts as a homodimer. The biological validity of the alternatively spliced transcript variants has not been determined.

The protein kinase A holoenzyme is a heterotetramer composed of two types of subunits: Catalytic and Regulatory. The Catalyticsubunit contains the enzyme's active site. It also contains a domain that binds ATP and a domain that binds the regulatory subunit. The Regulatory subunit consists oftwo molecules which bind one another in an anti-parallel orientation to form a homodimer; for type I subunits- this binding is covalent via disulfide bonds. This subunit also has has two domains that bind cyclic AMP, a domain that interacts with a catalytic subunit, and an "auto-inhibitory" domain that serves as a substrate or pseudosubstrate for the catalytic subunit. Regulatory subunits may also have biologic activity distinct from their role in modulating catalytic subunit activity. Regulatory subunits exist in two major forms, RI and RII, with each form having two subtypes designated alpha and beta. Each of the four isotypes of the regulatory subunit is encoded by a different gene. In addition, three isotypes of the catalytic subunit have been identified (alpha, beta and gamma). The different isotypes tend to have different distributions within cells and among tissues. Type I enzymes inhabit cytoplasmic, soluble fractions of the cell, whereas type II enzymes tend to associate with cellular membranes.

CKMT1A is in charge of the transfer of high energy phosphate from mitochondria to the cytosolic carrier, creatine. CKMT1A is a member of the creatine kinase isoenzyme family and exists as two isoenzymes, sarcomeric MtCK and ubiquitous MtCK, encoded by separate genes. Mitochondrial creatine kinase arises in two different oligomeric forms: dimers and octamers, unlike the exclusively dimeric cytosolic creatine kinase isoenzymes. Numerous malignant cancers with poor prognosis have displayed overexpression of ubiquitous mitochondrial creatine kinase which is linked to high energy turnover and inability to remove cancer cells through apoptosis.

E.Coli Acetate Kinase, also knowns as ACKA, catalyzes the formation of acetyl phosphate from acetate and ATP and also catalyzes the reverse reaction. ACKA takes part in synthesis of various ATP formed catabolically during anaerobic growth of the organism.

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.

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.

D-gluconate kinase or idnk is a thermosensitive protein, consists of 187 a.a and part of the gluconokinase gntK/gntV protein family. Idnk enhances the conversion of ATP + D-gluconate => ADP + 6-phospho-D-gluconate. Idnk has a crucial part in determination of gender, removal of a certain portion of 9p may result in the making of male to female (reversal of sex), that leads to a female that has the genotype of male X, Y.

Protein Kinase IFN Double Stranded RNA Activator, also known as PRKRA, mediates the effects of interferon when a viral infection takes place. PRKRA activates EIF2AK2/PKR in the absence of double-stranded RNA (dsRNA) and leads to phosphorylation of EIF2S1/EFI2-alpha and inhibition of translation and induction of apoptosis. Mutations in PRKRA are associated with dystonia.

NEK7, protein kinase, has a vital role in mitotic cell cycle progression. It is essential for microtubule nucleation activity of the centrosome, robust mitotic spindle formation and cytokinesis. NEK7 is greatly expressed in lung, muscle, testis, brain, heart, liver, leukocyte and spleen.

cAMP-dependent protein kinase catalytic subunit alpha isoform Calpha1 (PRKACA) belongs to the Ser/Thr protein kinase family. PRKACA is responsible for phosphorylating other proteins and substrates, changing their activity. The PRKACA protein is a member of the AGC kinase family, and contributes to the regulation of cellular processes which include glucose metabolism, cell division, and contextual memory.

p38a/SAPK2 is a member of the MAP kinase family. MAP kinases act as an integration point for multiple biochemical signals, and are involved in a wide variety of cellular processes such as proliferation, differentiation, transcription regulation and development. This kinase is activated by various environmental stresses and proinflammatory cytokines. The activation requires its phosphorylation by MAP kinase kinases (MKKs), or its autophosphorylation triggered by the interaction of MAP3K7IP1/TAB1 protein with this kinase. The substrates of this kinase include transcription regulator ATF2, MEF2C, and MAX, cell cycle regulator CDC25B, and tumor suppressor p53, which suggest the roles of this kinase in stress related transcription and cell cycle regulation, as well as in genotoxic stress response. Four alternatively spliced transcript variants of this gene encoding distinct isoforms have been reported.

pykF (pyruvate kinase I) is a member of the pyruvate kinase family. pykF is an enzyme involved in glycolysis. pykF catalyzes the transfer of a phosphate group from phosphoenolpyruvate (PEP) to ADP, yielding one molecule of pyruvate and one molecule of ATP, a process which also requires a Magnesium ion. This is the final step in the glycolytic pathway, which produces pyruvate molecules, the ultimate product of aerobic glycolysis.

ILK1 (Integrin-linked kinase) is a serine/threonine protein kinase, containing 4 ankyrin-like repeats. ILK1 regulates a number of biological properties which include: anchorage-independent cell cycle progression, tumor cell invasion and apoptosis. ILK1 can also be implicated in mediating cell architecture, adhesion to integrin substrates and anchorage-dependent growth in epithelial cells. Furthermore, ILK1 phosphorylates beta-1 and beta-3 integrin subunit on serine and threonine residues, but also AKT1 and GSK3B.
ILK1 interacts with the cytoplasmic domains of integrin ?1 and ?3 subunits in addition to several adaptors and signaling proteins, it also acts as a proximal receptor kinase regulating integrin-mediated signal transduction. ILK1 is a focal adhesion protein part of the complex ILK-PINCH. This complex is deemed to be one of the convergence points of integrin- and growth factor-signaling pathway. ILK1 is stimulated rapidly but briefly by both cell fibronectin interactions in a PI3-K-dependent manner, probably through the binding of PtdIns(3,4,5)P3 with a PH-like domain of ILK.
ILK1 over-expression has been documented in a wide variety of human malignancies.

Akt1, also known as "Akt" or protein kinaseB (PKB) is an important molecule in mammaliancellular signaling.
In humans, there are three genes in the "Akt family": Akt1, Akt2, and Akt3. These enzymesare members of the serine/threonine-specific protein kinasefamily (EC2.7.11.1).
Akt1 is involved in cellular survival pathways, by inhibiting apoptoticprocesses. Akt1 is also able to induce protein synthesispathways, and is therefore a key signaling protein in the cellular pathways that lead to skeletal muscle hypertrophy, and general tissue growth. Since it can block apoptosis, and thereby promote cell survival, Akt1 has been implicated as a major factor in many types of cancer. Akt (now also called Akt1) was originally identified as the oncogenein the transforming retrovirus, AKT8.

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 IFN. Mice which do not express an active protein for JAK2 show embryonic lethality associated with the absence of definitive erythropoiesis.

UCK2 is a member of the uridinekinase family. UCK2 catalyzes the phosphorylation of uridine monophosphate to uridine diphosphate and cytidine monophosphate. UCK2 has a part in the production of pyrimidine nucleoside triphosphates essential for RNA and DNA synthesis. Furthermore, an allele of this gene is an important player in mediating nonhumoral immunity to Hemophilus influenzae type B.

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.

MAP kinase-activated protein kinase 3 (MAPKAPK3) is involved in inflammatory Reaction by regulating tumor necrosis factor (TNF) and IL6 production post-transcriptionally. MAPKAPK3 phosphorylates AU-rich elements (AREs)-binding proteins, like TTP/ZFP36, leading to control of stability and translation of TNF and IL6 mRNAs. Phosphorylation of TTP/ZFP36 (a major post-transcriptional regulator of TNF), promotes its binding to 14-3-3 proteins and reduces its ARE mRNA affinity resulting in inhibition of dependent degradation of ARE-containing transcript. MAPKAPK3 is activated by growth inducers and stress stimulation of cells.

Mitogen-Activated Protein Kinase Kinase 2 (MAP2K2) is a dual specificity protein kinase, which is a member of the STE grouping of kinases and the MAP kinase kinase family. MAP2K2 is activated by a wide range of growth factors and cytokines and also by membrane depolarization and calcium influx. The MAP2K2 kinase is known for its vital role in mitogen growth factor signal transduction. MAP2K2 phosphorylates and consequently activates MAPK1/ERK2 and MAPK2/ERK3. The activation of the MAP2K2 kinase itself is dependent on the Ser/Thr phosphorylation by MAP kinase kinase kinases. The inhibition or degradation of the MAP2K2 kinase is also found to be involved in the pathogenesis of Yersinia and anthrax. MAP2K2 gene mutations cause cardiofaciocutaneous syndrome (CFC syndrome).

B lymphoid kinase (BLK) is a 55kDa tyrosine kinase with SH3, SH2, and catalytic domains which contain consensus sequences of the Src protein tyrosine kinase family. BLK is a nonreceptor tyrosine-kinase belonging to the src family of proto-oncogenes which are typically involved in cell proliferation and differentiation. The BLK protein is expressed specifically in the B cell lineage and has a role in the signal-transduction pathway which is restricted to B lymphoid cells. In addition, BLK stimulates ins. synthesis and secretion in response to glucose and increases the expression of several pancreatic beta-cell transcription factors.

GUK1 is part of the guanylate kinase family. GUK1 occurs as a monomer that catalyzes the ATP-dependent conversion of GMP to GDP, thus takes an important part in the recycling of GMP. Through its catalytic activity, GUK1 functions in regulation of the supply of guanine nucleotides to signal transduction pathways. GUK1 overexpression is related with pituitary adenocarcinomas, implicating that GUK1 is has a role in tumorigenesis.