Functional analysis of the catalytic subunit of Dictyostelium PKA in vivo.
The catalytic subunit of the cAMP-dependent protein kinase (PKA) from Dictyostelium discoideum contains several domains, including an unusually long N-terminal extension preceding a highly conserved catalytic core. We transformed the aggregationless PkaC-null strain with several deletion constructs of both domains. Strains transformed with genes expressing catalytically-inactive polypeptides could not rescue development. Cotransformation with constructs encoding the N-terminal extension and the catalytic core, both unable to rescue development by themselves, yielded transformants able to proceed to late development. A 27-amino acid long hydrophobic region, immediately upstream of the catalytic core, was found indispensable for PKA function. A putative role of this sequence in the acquisition of the active conformation of the protein is discussed.
Dammann
H
H
Unité de Régulation Enzymatique des Activités Cellulaires, Institut Pasteur, 25 rue du Dr. Roux, 75724, Paris Cedex 15, France.
Traincard
F
F
Anjard
C
C
van Bemmelen
M X
MX
Reymond
C
C
Véron
M
M
D000595:Amino Acid Sequence; D000818:Animals; D002384:Catalysis; D017868:Cyclic AMP-Dependent Protein Kinases / Q000235:genetics / Q000378:metabolism*; D004023:Dictyostelium / Q000201:enzymology* / Q000235:genetics; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D011487:Protein Conformation; D013329:Structure-Activity Relationship
D017868:Cyclic AMP-Dependent Protein Kinases