Protein Kinases, catalytic domain; The protein kinase superfamily is mainly composed of the catalytic domains of serine/threonine-specific and tyrosine-specific protein kinases. It also includes RIO kinases, which are atypical serine protein kinases, aminoglycoside phosphotransferases, and choline kinases. These proteins catalyze the transfer of the gamma-phosphoryl group from ATP to hydroxyl groups in specific substrates such as serine, threonine, or tyrosine residues of proteins.

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gi 961554807   1 KPLGRGAFGQVIEADAFGIDKTATCRTVAVKMLK 34
Cdd:cd05103   13 KPLGRGAFGQVIEADAFGIDKTATCRTVAVKMLK 46

Catalytic domain of the Protein Tyrosine Kinase, Vascular Endothelial Growth Factor Receptor 2; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. VEGFR2 (or Flk1) binds the ligands VEGFA, VEGFC, VEGFD and VEGFE. VEGFR2 signaling is implicated in all aspects of normal and pathological vascular endothelial cell biology. It induces a variety of cellular effects including migration, survival, and proliferation. It is critical in regulating embryonic vascular development and angiogenesis. VEGFR2 is the major signal transducer in pathological angiogenesis including cancer and diabetic retinopathy, and is a target for inhibition in cancer therapy. The carboxyl terminus of VEGFR2 plays an important role in its autophosphorylation and activation. VEGFR2 is a member of the VEGFR subfamily of proteins, which are receptor PTKs (RTKs) containing an extracellular ligand-binding region with seven immunoglobulin (Ig)-like domains, a transmembrane segment, and an intracellular catalytic domain. The binding of VEGFRs to their ligands, the VEGFs, leads to receptor dimerization, activation, and intracellular signaling. The VEGFR2 subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 961554807   1 KPLGRGAFGQVIEADAFGIDKTATCRTVAVKMLK 34
Cdd:cd05103   13 KPLGRGAFGQVIEADAFGIDKTATCRTVAVKMLK 46

Tyrosine kinase, catalytic domain; Phosphotransferases. Tyrosine-specific kinase subfamily.

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gi 961554807     1 KPLGRGAFGQVIEADAFGIDKTaTCRTVAVKMLK 34
Cdd:smart00219   5 KKLGEGAFGEVYKGKLKGKGGK-KKVEVAVKTLK 37

Catalytic domain of the Protein Tyrosine Kinase, Vascular Endothelial Growth Factor Receptor 2; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. VEGFR2 (or Flk1) binds the ligands VEGFA, VEGFC, VEGFD and VEGFE. VEGFR2 signaling is implicated in all aspects of normal and pathological vascular endothelial cell biology. It induces a variety of cellular effects including migration, survival, and proliferation. It is critical in regulating embryonic vascular development and angiogenesis. VEGFR2 is the major signal transducer in pathological angiogenesis including cancer and diabetic retinopathy, and is a target for inhibition in cancer therapy. The carboxyl terminus of VEGFR2 plays an important role in its autophosphorylation and activation. VEGFR2 is a member of the VEGFR subfamily of proteins, which are receptor PTKs (RTKs) containing an extracellular ligand-binding region with seven immunoglobulin (Ig)-like domains, a transmembrane segment, and an intracellular catalytic domain. The binding of VEGFRs to their ligands, the VEGFs, leads to receptor dimerization, activation, and intracellular signaling. The VEGFR2 subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 961554807   1 KPLGRGAFGQVIEADAFGIDKTATCRTVAVKMLK 34
Cdd:cd05103   13 KPLGRGAFGQVIEADAFGIDKTATCRTVAVKMLK 46

Catalytic domain of the Protein Tyrosine Kinases, Vascular Endothelial Growth Factor Receptors; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. VEGFR1 (or Flt1) binds VEGFA, VEGFB, and placenta growth factor (PLGF). It regulates monocyte and macrophage migration, vascular permeability, haematopoiesis, and the recruitment of haematopietic progenitor cells from the bone marrow. VEGFR1 is a member of the VEGFR subfamily of proteins, which are receptor PTKs (RTKs) containing an extracellular ligand-binding region with seven immunoglobulin (Ig)-like domains, a transmembrane segment, and an intracellular catalytic domain. The binding of VEGFRs to their ligands, the VEGFs, leads to receptor dimerization, activation, and intracellular signaling. The VEGFR1 subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 961554807   1 KPLGRGAFGQVIEADAFGIDKTATCRTVAVKMLK 34
Cdd:cd14207   13 KSLGRGAFGKVVQASAFGIKKSPTCRVVAVKMLK 46

Catalytic domain of the Protein Tyrosine Kinases, Fibroblast Growth Factor Receptors; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. The FGFR subfamily consists of FGFR1, FGFR2, FGFR3, FGFR4, and similar proteins. They are receptor PTKs (RTKs) containing an extracellular ligand-binding region with three immunoglobulin-like domains, a transmembrane segment, and an intracellular catalytic domain. The binding of FGFRs to their ligands, the FGFs, and to heparin/heparan sulfate (HS) results in the formation of a ternary complex, which leads to receptor dimerization and activation, and intracellular signaling. There are at least 23 FGFs and four types of FGFRs. The binding of FGFs to FGFRs is promiscuous, in that a receptor may be activated by several ligands and a ligand may bind to more that one type of receptor. FGF/FGFR signaling is important in the regulation of embryonic development, homeostasis, and regenerative processes. Depending on the cell type and stage, FGFR signaling produces diverse cellular responses including proliferation, growth arrest, differentiation, and apoptosis. Aberrant signaling leads to many human diseases such as skeletal, olfactory, and metabolic disorders, as well as cancer. The FGFR subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase .

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gi 961554807   1 KPLGRGAFGQVIEADAFGIDKTATCR-TVAVKMLK 34
Cdd:cd05053   18 KPLGEGAFGQVVKAEAVGLDNKPNEVvTVAVKMLK 52

Catalytic domain of the Protein Tyrosine Kinases, Platelet Derived Growth Factor Receptors; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. The PDGFR subfamily consists of PDGFR alpha, PDGFR beta, KIT, CSF-1R, the mammalian FLT3, and similar proteins. They are receptor PTKs (RTKs) containing an extracellular ligand-binding region with five immunoglobulin-like domains, a transmembrane segment, and an intracellular catalytic domain. PDGFR kinase domains are autoinhibited by their juxtamembrane regions containing tyr residues. The binding to their ligands leads to receptor dimerization, trans phosphorylation and activation, and intracellular signaling. PDGFR subfamily receptors are important in the development of a variety of cells. PDGFRs are expressed in a many cells including fibroblasts, neurons, endometrial cells, mammary epithelial cells, and vascular smooth muscle cells. PDGFR signaling is critical in normal embryonic development, angiogenesis, and wound healing. Kit is important in the development of melanocytes, germ cells, mast cells, hematopoietic stem cells, the interstitial cells of Cajal, and the pacemaker cells of the GI tract. CSF-1R signaling is critical in the regulation of macrophages and osteoclasts. Mammalian FLT3 plays an important role in the survival, proliferation, and differentiation of stem cells. The PDGFR subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase .

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gi 961554807   1 KPLGRGAFGQVIEADAFGIDKTATCRTVAVKMLK 34
Cdd:cd05055   41 KTLGAGAFGKVVEATAYGLSKSDAVMKVAVKMLK 74

Catalytic domain of the Protein Tyrosine Kinase, Fibroblast Growth Factor Receptor 3; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Many FGFR3 splice variants have been reported with the IIIb and IIIc isoforms being the predominant forms. FGFR3 IIIc is the isoform expressed in chondrocytes, the cells affected in dwarfism, while IIIb is expressed in epithelial cells. FGFR3 ligands include FGF1, FGF2, FGF4, FGF8, FGF9, and FGF23. It is a negative regulator of long bone growth. In the cochlear duct and in the lens, FGFR3 is involved in differentiation while it appears to have a role in cell proliferation in epithelial cells. Germline mutations in FGFR3 are associated with skeletal disorders including several forms of dwarfism. Some missense mutations are associated with multiple myeloma and carcinomas of the bladder and cervix. Overexpression of FGFR3 is found in thyroid carcinoma. FGFR3 is part of the FGFR subfamily, which are receptor PTKs (RTKs) containing an extracellular ligand-binding region with three immunoglobulin-like domains, a transmembrane segment, and an intracellular catalytic domain. The binding of FGFRs to their ligands, the FGFs, results in receptor dimerization and activation, and intracellular signaling. The binding of FGFs to FGFRs is promiscuous, in that a receptor may be activated by several ligands and a ligand may bind to more that one type of receptor. The FGFR3 subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 961554807   1 KPLGRGAFGQVIEADAFGIDKTATCR--TVAVKMLK 34
Cdd:cd05100   18 KPLGEGCFGQVVMAEAIGIDKDKPNKpvTVAVKMLK 53

Catalytic domain of the Protein Tyrosine Kinase, Fibroblast Growth Factor Receptor 2; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. There are many splice variants of FGFR2 which show differential expression and binding to FGF ligands. Disruption of either FGFR2 or FGFR2b is lethal in mice, due to defects in the placenta or severe impairment of tissue development including lung, limb, and thyroid, respectively. Disruption of FGFR2c in mice results in defective bone and skull development. Genetic alterations of FGFR2 are associated with many human skeletal disorders including Apert syndrome, Crouzon syndrome, Jackson-Weiss syndrome, and Pfeiffer syndrome. FGFR2 is part of the FGFR subfamily, which are receptor PTKs (RTKs) containing an extracellular ligand-binding region with three immunoglobulin-like domains, a transmembrane segment, and an intracellular catalytic domain. The binding of FGFRs to their ligands, the FGFs, results in receptor dimerization and activation, and intracellular signaling. The binding of FGFs to FGFRs is promiscuous, in that a receptor may be activated by several ligands and a ligand may bind to more that one type of receptor. The FGFR2 subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 961554807   1 KPLGRGAFGQVIEADAFGIDKT--ATCRTVAVKMLK 34
Cdd:cd05101   30 KPLGEGCFGQVVMAEAVGIDKDkpKEAVTVAVKMLK 65

Catalytic domain of Protein Tyrosine Kinases; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. They can be classified into receptor and non-receptor tyr kinases. PTKs play important roles in many cellular processes including, lymphocyte activation, epithelium growth and maintenance, metabolism control, organogenesis regulation, survival, proliferation, differentiation, migration, adhesion, motility, and morphogenesis. Receptor tyr kinases (RTKs) are integral membrane proteins which contain an extracellular ligand-binding region, a transmembrane segment, and an intracellular tyr kinase domain. RTKs are usually activated through ligand binding, which causes dimerization and autophosphorylation of the intracellular tyr kinase catalytic domain, leading to intracellular signaling. Some RTKs are orphan receptors with no known ligands. Non-receptor (or cytoplasmic) tyr kinases are distributed in different intracellular compartments and are usually multi-domain proteins containing a catalytic tyr kinase domain as well as various regulatory domains such as SH3 and SH2. PTKs are usually autoinhibited and require a mechanism for activation. In many PTKs, the phosphorylation of tyr residues in the activation loop is essential for optimal activity. Aberrant expression of PTKs is associated with many development abnormalities and cancers.The PTK family is part of a larger superfamily that includes the catalytic domains of serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 961554807   1 KPLGRGAFGQVIEADAFGIDKtaTCRTVAVKMLK 34
Cdd:cd00192    1 KKLGEGAFGEVYKGKLKGGDG--KTVDVAVKTLK 32

Protein tyrosine and serine/threonine kinase; Protein phosphorylation, which plays a key role in most cellular activities, is a reversible process mediated by protein kinases and phosphoprotein phosphatases. Protein kinases catalyze the transfer of the gamma phosphate from nucleotide triphosphates (often ATP) to one or more amino acid residues in a protein substrate side chain, resulting in a conformational change affecting protein function. Phosphoprotein phosphatases catalyze the reverse process. Protein kinases fall into three broad classes, characterized with respect to substrate specificity; Serine/threonine-protein kinases, tyrosine-protein kinases, and dual specificity protein kinases (e.g. MEK - phosphorylates both Thr and Tyr on target proteins). This entry represents the catalytic domain found in a number of serine/threonine- and tyrosine-protein kinases. It does not include the catalytic domain of dual specificity kinases.

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gi 961554807    1 KPLGRGAFGQVIEADAFGiDKTATCRTVAVKMLK 34
Cdd:pfam07714   5 EKLGEGAFGEVYKGTLKG-EGENTKIKVAVKTLK 37

Catalytic domain of the Protein Tyrosine Kinase, Platelet Derived Growth Factor Receptor alpha; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. PDGFR alpha is a receptor PTK (RTK) containing an extracellular ligand-binding region with five immunoglobulin-like domains, a transmembrane segment, and an intracellular catalytic domain. The binding to its ligands, the PDGFs, leads to receptor dimerization, trans phosphorylation and activation, and intracellular signaling. PDGFR alpha forms homodimers or heterodimers with PDGFR beta, depending on the nature of the PDGF ligand. PDGF-AA, PDGF-AB, and PDGF-CC induce PDGFR alpha homodimerization. PDGFR signaling plays many roles in normal embryonic development and adult physiology. PDGFR alpha signaling is important in the formation of lung alveoli, intestinal villi, mesenchymal dermis, and hair follicles, as well as in the development of oligodendrocytes, retinal astrocytes, neural crest cells, and testicular cells. Aberrant PDGFR alpha expression is associated with some human cancers. Mutations in PDGFR alpha have been found within a subset of gastrointestinal stromal tumors (GISTs). An active fusion protein FIP1L1-PDGFR alpha, derived from interstitial deletion, is associated with idiopathic hypereosinophilic syndrome and chronic eosinophilic leukemia. The PDGFR alpha subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 961554807   3 LGRGAFGQVIEADAFGIDKTATCRTVAVKMLK 34
Cdd:cd05105   45 LGSGAFGKVVEGTAYGLSRSQPVMKVAVKMLK 76

Catalytic domain of the Protein Tyrosine Kinase, REarranged during Transfection protein; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. RET is a receptor PTK (RTK) containing an extracellular region with four cadherin-like repeats, a calcium-binding site, and a cysteine-rich domain, a transmembrane segment, and an intracellular catalytic domain. It is part of a multisubunit complex that binds glial-derived neurotropic factor (GDNF) family ligands (GFLs) including GDNF, neurturin, artemin, and persephin. GFLs bind RET along with four GPI-anchored coreceptors, bringing two RET molecules together, leading to autophosphorylation, activation, and intracellular signaling. RET is essential for the development of the sympathetic, parasympathetic and enteric nervous systems, and the kidney. RET disruption by germline mutations causes diseases in humans including congenital aganglionosis of the gastrointestinal tract (Hirschsprung's disease) and three related inherited cancers: multiple endocrine neoplasia type 2A (MEN2A), MEN2B, and familial medullary thyroid carcinoma. The RET subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 961554807   1 KPLGRGAFGQVIEADAFGIDKTATCRTVAVKMLK 34
Cdd:cd05045    6 KTLGEGEFGKVVKATAFRLKGRAGYTTVAVKMLK 39

Catalytic domain of the Protein Tyrosine Kinase, C-ros; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. This subfamily contains c-ros, Sevenless, and similar proteins. The proto-oncogene c-ros encodes an orphan receptor PTK (RTK) with an unknown ligand. RTKs contain an extracellular ligand-binding domain, a transmembrane region, and an intracellular tyr kinase domain. RTKs are usually activated through ligand binding, which causes dimerization and autophosphorylation of the intracellular tyr kinase catalytic domain. C-ros is expressed in embryonic cells of the kidney, intestine and lung, but disappears soon after birth. It persists only in the adult epididymis. Male mice bearing inactive mutations of c-ros lack the initial segment of the epididymis and are infertile. The Drosophila protein, Sevenless, is required for the specification of the R7 photoreceptor cell during eye development. The c-ros subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 961554807   3 LGRGAFGQVIEADAFGIDKTATCRT-VAVKMLK 34
Cdd:cd05044    3 LGSGAFGEVFEGTAKDILGDGSGETkVAVKTLR 35

Catalytic domain of the Serine/Threonine kinase, Oocyte maturation factor Mos; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. Mos (or c-Mos) is a germ-cell specific kinase that plays roles in both the release of primary arrest and the induction of secondary arrest in oocytes. It is expressed towards the end of meiosis I and is quickly degraded upon fertilization. It is a component of the cytostatic factor (CSF), which is responsible for metaphase II arrest. In addition, Mos activates a phoshorylation cascade that leads to the activation of the p34 subunit of MPF (mitosis-promoting factor or maturation promoting factor), a cyclin-dependent kinase that is responsible for the release of primary arrest in meiosis I. The Mos subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 961554807   2 PLGRGAFGQVIEADAFGidktatcRTVAVKMLK 34
Cdd:cd13979   10 PLGSGGFGSVYKATYKG-------ETVAVKIVR 35

Catalytic Domain of the Protein Tyrosine Kinases, Receptor tyrosine kinase-like Orphan Receptors; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. The Ror subfamily consists of Ror1, Ror2, and similar proteins. Ror proteins are orphan receptor PTKs (RTKs) containing an extracellular region with immunoglobulin-like, cysteine-rich, and kringle domains, a transmembrane segment, and an intracellular catalytic domain. Ror RTKs are unrelated to the nuclear receptor subfamily called retinoid-related orphan receptors (RORs). RTKs are usually activated through ligand binding, which causes dimerization and autophosphorylation of the intracellular tyr kinase catalytic domain. Ror kinases are expressed in many tissues during development. They play important roles in bone and heart formation. Mutations in human Ror2 result in two different bone development genetic disorders, recessive Robinow syndrome and brachydactyly type B. Drosophila Ror is expressed only in the developing nervous system during neurite outgrowth and neuronal differentiation, suggesting a role for Drosophila Ror in neural development. More recently, mouse Ror1 and Ror2 have also been found to play an important role in regulating neurite growth in central neurons. Ror1 and Ror2 are believed to have some overlapping and redundant functions. The Ror subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 961554807   1 KPLGRGAFGQVIEADAFGIDKTATCRTVAVKMLK 34
Cdd:cd05048   11 EELGEGAFGKVYKGELLGPSSEESAISVAIKTLK 44

Protein kinase domain;

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gi 961554807    1 KPLGRGAFGQVIEAdafgIDKtATCRTVAVKMLK 34
Cdd:pfam00069   5 RKLGSGSFGTVYKA----KHR-DTGKIVAIKKIK 33

Catalytic domain of the Serine/Threonine Kinase, Mitogen-Activated Protein Kinase; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. MAPKs serve as important mediators of cellular responses to extracellular signals. They control critical cellular functions including differentiation, proliferation, migration, and apoptosis. They are also implicated in the pathogenesis of many diseases including multiple types of cancer, stroke, diabetes, and chronic inflammation. Typical MAPK pathways involve a triple kinase core cascade comprising of the MAPK, which is phosphorylated and activated by a MAPK kinase (MAP2K or MKK), which itself is phosphorylated and activated by a MAPK kinase kinase (MAP3K or MKKK). Each cascade is activated either by a small GTP-binding protein or by an adaptor protein, which transmits the signal either directly to a MAP3K to start the triple kinase core cascade or indirectly through a mediator kinase, a MAP4K. There are three typical MAPK subfamilies: Extracellular signal-Regulated Kinase (ERK), c-Jun N-terminal Kinase (JNK), and p38. Some MAPKs are atypical in that they are not regulated by MAP2Ks. These include MAPK4, MAPK6, NLK, and ERK7. The MAPK subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 961554807   1 KPLGRGAFGQVIEAdafgIDKTaTCRTVAVKML 33
Cdd:cd07834    6 KPIGSGAYGVVCSA----YDKR-TGRKVAIKKI 33

Catalytic domain of the Protein Tyrosine Kinases, Tropomyosin Related Kinases; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. The Trk subfamily consists of TrkA, TrkB, TrkC, and similar proteins. They are receptor PTKs (RTKs) containing an extracellular region with arrays of leucine-rich motifs flanked by two cysteine-rich clusters followed by two immunoglobulin-like domains, a transmembrane segment, and an intracellular catalytic domain. Binding to their ligands, the nerve growth factor (NGF) family of neutrotrophins, leads to Trk receptor oligomerization and activation of the catalytic domain. Trk receptors are mainly expressed in the peripheral and central nervous systems. They play important roles in cell fate determination, neuronal survival and differentiation, as well as in the regulation of synaptic plasticity. Altered expression of Trk receptors is associated with many human diseases. The Trk subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 961554807   3 LGRGAFGQVIEADAFGIDKTATCRTVAVKMLK 34
Cdd:cd05049   13 LGEGAFGKVFLGECYNLEPEQDKMLVAVKTLK 44

Catalytic domain of the Serine/Threonine Kinase, Phosphoinositide-dependent kinase 1; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. PDK1 carries an N-terminal catalytic domain and a C-terminal pleckstrin homology (PH) domain that binds phosphoinositides. It phosphorylates the activation loop of AGC kinases that are regulated by PI3K such as PKB, SGK, and PKC, among others, and is crucial for their activation. Thus, it contributes in regulating many processes including metabolism, growth, proliferation, and survival. PDK1 also has the ability to autophosphorylate and is constitutively active in mammalian cells. It is essential for normal embryo development and is important in regulating cell volume. The PDK1 subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 961554807   1 KPLGRGAFGQVIEAdafgIDKTaTCRTVAVKMLK 34
Cdd:cd05581    7 KPLGEGSYSTVVLA----KEKE-TGKEYAIKVLD 35