Characterisation of a plant 3-phosphoinositide-dependent protein kinase-1 homologue which contains a pleckstrin homology domain.
A plant homologue of mammalian 3-phosphoinositide-dependent protein kinase-1 (PDK1) has been identified in Arabidopsis and rice which displays 40% overall identity with human 3-phosphoinositide-dependent protein kinase-1. Like the mammalian 3-phosphoinositide-dependent protein kinase-1, Arabidopsis 3-phosphoinositide-dependent protein kinase-1 and rice 3-phosphoinositide-dependent protein kinase-1 possess a kinase domain at N-termini and a pleckstrin homology domain at their C-termini. Arabidopsis 3-phosphoinositide-dependent protein kinase-1 can rescue lethality in Saccharomyces cerevisiae caused by disruption of the genes encoding yeast 3-phosphoinositide-dependent protein kinase-1 homologues. Arabidopsis 3-phosphoinositide-dependent protein kinase-1 interacts via its pleckstrin homology domain with phosphatidic acid, PtdIns3P, PtdIns(3,4,5)P3 and PtdIns(3,4)P2 and to a lesser extent with PtdIns(4,5)P2 and PtdIns4P. Arabidopsis 3-phosphoinositide-dependent protein kinase-1 is able to activate human protein kinase B alpha (PKB/AKT) in the presence of PtdIns(3,4,5)P3. Arabidopsis 3-phosphoinositide-dependent protein kinase-1 is only the second plant protein reported to possess a pleckstrin homology domain and the first plant protein shown to bind 3-phosphoinositides.
Deak
M
M
Department of Biochemistry, University of Dundee, UK. mdeak@bad.dundee.ac.uk
Casamayor
A
A
Currie
R A
RA
Downes
C P
CP
Alessi
D R
DR
D064413:3-Phosphoinositide-Dependent Protein Kinases; D000595:Amino Acid Sequence; D001483:Base Sequence; D001798:Blood Proteins / Q000235:genetics*; D003001:Cloning, Molecular; D017343:Genes, Plant; D006801:Humans; D008969:Molecular Sequence Data; D010750:Phosphoproteins; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D010944:Plants / Q000235:genetics / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000235:genetics* / Q000378:metabolism; D017421:Sequence Analysis; D017385:Sequence Homology
D001798:Blood Proteins; D010750:Phosphoproteins; D010940:Plant Proteins; C039077:platelet protein P47; D064413:3-Phosphoinositide-Dependent Protein Kinases; C578562:PDPK1 protein, human; D017346:Protein Serine-Threonine Kinases