A Go-like protein in Drosophila melanogaster and its expression in memory mutants.
G proteins couple receptors for extracellular signals to several intracellular effector systems and play a key role in signalling transduction mechanisms. In particulate preparations of Drosophila melanogaster heads, only one substrate for pertussis toxin at 39-40 kd was detected. This substrate, which showed only one isoform when analysed by isoelectric focusing, was recognized by immunoblotting and immunoprecipitation techniques using a polyclonal antibody against the alpha subunit of the Go protein purified from bovine brain and can be thus considered as a Go-like protein. Antibodies obtained against a carboxy-terminal sequence of the alpha subunit of Go (but not of Gi1 or Gi2) and against an internal sequence shared by all the alpha subunits, were also able to cross-react with the alpha subunit of this protein in insects. We have also studied the Go-like protein in several D.melanogaster mutants, primarily in memory and learning mutants. In these mutants there was a sex-dependent enhancement in pertussis toxin-catalysed ADP-ribosylation with respect to the wild-type. This increase could be attributed in part to an increase in the alpha subunit of the Go-like protein, as revealed by immunoblotting with anti-Go alpha polyclonal antibody. This report constitutes the first evidence for the participation of a Go protein in learning and memory.
Guillén
A
A
Centre CNRS-INSERM de Pharmacologie-Endocrinologie, Montpellier, France.
Jallon
J M
JM
Fehrentz
J A
JA
Pantaloni
C
C
Bockaert
J
J
Homburger
V
V
D000246:Adenosine Diphosphate Ribose / Q000378:metabolism; D000818:Animals; D004331:Drosophila melanogaster / Q000235:genetics / Q000502:physiology*; D019204:GTP-Binding Proteins / Q000096:biosynthesis* / Q000235:genetics; D015151:Immunoblotting; D007525:Isoelectric Focusing; D007858:Learning / Q000502:physiology; D008565:Membrane Proteins / Q000378:metabolism; D008568:Memory / Q000502:physiology*; D009154:Mutation; D037342:Pertussis Toxin; D011233:Precipitin Tests; D012727:Sex Characteristics; D010566:Virulence Factors, Bordetella
D008565:Membrane Proteins; D010566:Virulence Factors, Bordetella; D000246:Adenosine Diphosphate Ribose; D037342:Pertussis Toxin; D019204:GTP-Binding Proteins