View source for Kinase Family PKA

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[[kinase classification|Kinase Classification]]: [[Kinase_Group_AGC|Group AGC]]: [[Kinase_Family_PKA|Family PKA]]

Protein Kinase A ('''PKA''') is a '''cAMP-dependent protein kinase''' with many cellular functions. It is activated by cAMP binding to its regulatory subunit, which then activates the catalytic subunit. In basal organisms, these two subunits may be fused.


The PKA family has the following subfamilies

====[[Kinase_Subfamily_PKA|Subfamily PKA]]====
Protein Kinase A is the best known structural and mechanistic model for the ePK superfamily. Three members are found in human, and the gene is found in most eukaryotes. It is activated by cyclic AMP and mediates a wide number of signaling functions.

====[[Kinase_Subfamily_PKX|Subfamily PKX]]====
In human, this consists of PRKX, on the X chromosome, and [[Kinase_PRKY|PRKY]], a possible pseudogene found on the Y chromosome. Preliminary analysis indicates that distinct PRKX genes (as opposed to PKA family genes) are found in both Drosophila and C. elegans.

====[[Kinase_Subfamily_PKAHP|Subfamily PKAHP]]====
This subfamily is found in land plants, at least one alga and stramenopiles (oomycetes). It consists of a PP2C phosphatase domain followed by a pair of cNMP-binding domains that are most similar to those of the PKA catalytic subunit, followed by a kinase domain that is most similar to the PKA catalytic subunit, but which has multiple changes that suggest it is a [[pseudokinases|pseudokinase]]. These proteins are often annotated as [[Kinase_Family_PKG|PKG]] since they contain both cNMP-binding and kinase domains in the one polypeptide, and PKG proteins are typically their best blast hits.

====[[Other_Basal_PKA|Other Basal PKA]]====
Several basal eukaryotic lineages have kinases that contain both cNMP-binding and kinase domains, with the domains most similar to those of animal PKA, but the domain arrangement similar to that of PKG. These have not yet been placed in defined subfamilies.

[[User:Gerard|Gerard]] 00:26, 8 March 2012 (UTC)