Characterisation of cAMP-dependent protein kinase isoforms in the brain of the crab Chasmagnathus

F. Locatelli, C. LaFourcade, H. Maldonado, A. Romano

Research output: Contribution to journalArticlepeer-review

16 Scopus citations

Abstract

In the crab Chasmagnathus learning model, systemic administration of cAMP analogues that are specific activators or inhibitors of cAMP-dependent protein kinase (PKA) proved to respectively facilitate or impair long-term retention. The aims of the present work were to analyse PKA activity distribution in the crab brain and to characterise PKA isoforms. The neuropils from the eyestalk showed higher levels of induced PKA activity when compared with other neuropils of the central nervous system. Two PKA isoforms, homologous to mammalian PKA I and PKA II, were detected from central brain protein extracts using DEAE chromatography. Only PKA II was found in lateral protocerebrum extracts, suggesting a role of this isoform in the processing of visual inputs and in the integration of this information with other sensory inputs. PKA I was observed to be ten-fold more sensitive to cAMP than PKA II. cGMP induced a high activation of both PKA isoforms, similar to that obtained with cAMP. PKA I showed a two-fold greater sensitivity for cGMP than PKA II. An autophosphorylation assay was performed and a protein of 55 kDa, corresponding to phosphorylated R II regulatory subunit, was detected. The presence of a PKA I isoform with high sensitivity for cAMP in the central brain suggests a role of this subtype in long-term memory.
Original languageAmerican English
Pages (from-to)33-40
Number of pages8
JournalJournal of Comparative Physiology - B Biochemical, Systemic, and Environmental Physiology
Volume171
Issue number1
DOIs
StatePublished - 1 Jan 2001
Externally publishedYes

Keywords

  • cAMP and cGMP
  • Crab brain
  • Memory
  • PKA autophosphorylation
  • PKA isoforms

Fingerprint Dive into the research topics of 'Characterisation of cAMP-dependent protein kinase isoforms in the brain of the crab Chasmagnathus'. Together they form a unique fingerprint.

Cite this