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 18412636 275 LSRSTAHQPNALSLLGTCEPeitVYKAPEIEVKLDNFNEKTDIYSFGIVFLSLALF 330
Cdd:cd00180 138 LAKDLDSDDSLLKTTGGTTP---PYYAPPELLGGRYYGPKVDIWSLGVILYELEEL 190

Catalytic domain of Protein Kinases; PKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine or tyrosine residues on protein substrates. PKs make up a large family of serine/threonine kinases (STKs), protein tyrosine kinases (PTKs), and dual-specificity PKs that phosphorylate both serine/threonine and tyrosine residues of target proteins. Majority of protein phosphorylation occurs on serine residues while only 1% occurs on tyrosine residues. Protein phosphorylation is a mechanism by which a wide variety of cellular proteins, such as enzymes and membrane channels, are reversibly regulated in response to certain stimuli. PKs often function as components of signal transduction pathways in which one kinase activates a second kinase, which in turn, may act on other kinases; this sequential action transmits a signal from the cell surface to target proteins, which results in cellular responses. The PK family is one of the largest known protein families with more than 100 homologous yeast enzymes and more than 500 human proteins. A fraction of PK family members are pseudokinases that lack crucial residues for catalytic activity. The mutiplicity of kinases allows for specific regulation according to substrate, tissue distribution, and cellular localization. PKs regulate many cellular processes including proliferation, division, differentiation, motility, survival, metabolism, cell-cycle progression, cytoskeletal rearrangement, immunity, and neuronal functions. Many kinases are implicated in the development of various human diseases including different types of cancer. The PK family is part of a larger superfamily that includes the catalytic domains of RIO kinases, aminoglycoside phosphotransferase, choline kinase, phosphoinositide 3-kinase (PI3K), and actin-fragmin kinase.

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gi 18412636 275 LSRSTAHQPNALSLLGTCEPeitVYKAPEIEVKLDNFNEKTDIYSFGIVFLSLALF 330
Cdd:cd00180 138 LAKDLDSDDSLLKTTGGTTP---PYYAPPELLGGRYYGPKVDIWSLGVILYELEEL 190

Catalytic domain of Protein Kinases; PKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine or tyrosine residues on protein substrates. PKs make up a large family of serine/threonine kinases (STKs), protein tyrosine kinases (PTKs), and dual-specificity PKs that phosphorylate both serine/threonine and tyrosine residues of target proteins. Majority of protein phosphorylation occurs on serine residues while only 1% occurs on tyrosine residues. Protein phosphorylation is a mechanism by which a wide variety of cellular proteins, such as enzymes and membrane channels, are reversibly regulated in response to certain stimuli. PKs often function as components of signal transduction pathways in which one kinase activates a second kinase, which in turn, may act on other kinases; this sequential action transmits a signal from the cell surface to target proteins, which results in cellular responses. The PK family is one of the largest known protein families with more than 100 homologous yeast enzymes and more than 500 human proteins. A fraction of PK family members are pseudokinases that lack crucial residues for catalytic activity. The mutiplicity of kinases allows for specific regulation according to substrate, tissue distribution, and cellular localization. PKs regulate many cellular processes including proliferation, division, differentiation, motility, survival, metabolism, cell-cycle progression, cytoskeletal rearrangement, immunity, and neuronal functions. Many kinases are implicated in the development of various human diseases including different types of cancer. The PK family is part of a larger superfamily that includes the catalytic domains of RIO kinases, aminoglycoside phosphotransferase, choline kinase, phosphoinositide 3-kinase (PI3K), and actin-fragmin kinase.

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                ....*....|....*....|....*....|....*....|....*....|....*.
gi 18412636 275 LSRSTAHQPNALSLLGTCEPeitVYKAPEIEVKLDNFNEKTDIYSFGIVFLSLALF 330
Cdd:cd00180 138 LAKDLDSDDSLLKTTGGTTP---PYYAPPELLGGRYYGPKVDIWSLGVILYELEEL 190

Catalytic domain of the Serine/Threonine kinase, With No Lysine (WNK) kinase; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. WNKs comprise a subfamily of STKs with an unusual placement of a catalytic lysine relative to all other protein kinases. They are critical in regulating ion balance and are thus, important components in the control of blood pressure. They are also involved in cell signaling, survival, proliferation, and organ development. WNKs are activated by hyperosmotic or low-chloride hypotonic stress and they function upstream of SPAK and OSR1 kinases, which regulate the activity of cation-chloride cotransporters through direct interaction and phosphorylation. There are four vertebrate WNKs which show varying expression patterns. WNK1 and WNK2 are widely expressed while WNK3 and WNK4 show a more restricted expression pattern. Because mutations in human WNK1 and WNK4 cause PseudoHypoAldosteronism type II (PHAII), characterized by hypertension (due to increased sodium reabsorption) and hyperkalemia (due to impaired renal potassium secretion), there are more studies conducted on these two proteins, compared to WNK2 and WNK3. The WNK 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 18412636 285 ALSLLGTcePEitvYKAPEIevKLDNFNEKTDIYSFGIVFLSLA 328
Cdd:cd13983 160 AKSVIGT--PE---FMAPEM--YEEHYDEKVDIYAFGMCLLEMA 196