Protein Kinase Evolution
Eukaryotic Protein Kinases (ePK)
Prokaryotic PKL Kinases
The ePKs are part of a larger family of kinases that share the same fold and catalytic mechanism, most of whom are prokaryotic, and many of which have non-protein substrates.
Archaeae
Archaeae have a very simple set of PKLs: every archaeal genome has a Bud32 kinase, and a Rio1 and Rio2 kinases. These kinases are also present in all eukaryotes, almost always in single copies (some metazoans have a Rio3). The functions of all three are relatively mysterious and varied, though the Rio's have been associated with translation, jibing with the commonality between eukaryotes and archaeae in the translational apparatus. Bud32 is associated with p53 and gene regulation in metazoans, and with telomere biology, which may also jibe with the archaeal-eukaryotic link in DNA biology.
As far as we know (in 2008), archaeae have no other PKL kinases.
