Two catalytic subunits of cAMP-dependent protein kinase generated by alternative RNA splicing are expressed in Aplysia neurons.
The amino acid sequences of two catalytic (C) subunits of Aplysia cAMP-dependent protein kinase (cAPK) have been deduced from the nucleotide sequences of cDNAs generated from neuronal poly(A)+ RNA. Both subunits contain 352 residues and are identical except for amino acids 142-183, which differ at 10 out of 42 positions. They derive from alternatively spliced transcripts of a single gene (CAPL) containing two mutually exclusive exon cassettes. CAPL transcripts are present in several classes of identified neurons containing transmitter-sensitive adenylate cyclase, including sensory cells, bag cells, and the left pleural giant cell. Combinatorial expression of the various regulatory (R) and C subunits might produce kinase isoforms with distinct roles in neuronal modulation. Alternatively, holoenzymes with overlapping properties together might contribute to the definition of individual cell types and physiological states.
Beushausen
S
S
Howard Hughes Medical Institute, Columbia University, New York, New York 10032.
Bergold
P
P
Sturner
S
S
Elste
A
A
Roytenberg
V
V
Schwartz
J H
JH
Bayley
H
H
D000595:Amino Acid Sequence; D000818:Animals; D001048:Aplysia / Q000166:cytology / Q000378:metabolism*; D001483:Base Sequence; D051379:Mice; D008969:Molecular Sequence Data; D009474:Neurons / Q000378:metabolism*; D009693:Nucleic Acid Hybridization; D011494:Protein Kinases / Q000235:genetics* / Q000378:metabolism; D012313:RNA / Q000378:metabolism*; D012326:RNA Splicing; D012689:Sequence Homology, Nucleic Acid
D012313:RNA; D011494:Protein Kinases