First published online May 11, 2006
Development 133, 1104e (2006)
© The Company of Biologists Limited
Dicty talk by GABAling
GABA (gamma amino butyric acid) is an important neurotransmitter in C.
elegans, Drosophila and all vertebrates. Now, Anjard and Loomis report that
GABA has another role in intercellular communication – inducing
sporulation in Dictyostelium (see
p. 2253). This
finding excitingly shows that GABA is not only an important neurotransmitter
but also an ancient intercellular signal. Towards the end of Dictyostelium
development, prespore cells migrate to the top of the fruiting body where they
encapsulate in response to a secreted peptide SDF-2, which is generated from a
precursor, AcbA, by a prestalk-specific protease. The researchers show that
GABA triggers the release and processing of AcbA. By examining the
Dictyostelium genome, they identified a putative receptor for GABA–GrlE.
Dictyostelium cells that lack this G-protein-coupled receptor did not produce
SDF-2 in response to GABA. Finally, the authors used pharmacological
inhibitors and specific mutations to reveal that the effects of GABA on
sporulation are mediated by PI3 kinase and a protein kinase B-related kinase,
proteins that often act downstream of G-protein-coupled receptors.
Related articles in Development:
- GABA induces terminal differentiation of Dictyostelium through a GABAB receptor
- Christophe Anjard and William F. Loomis
Development 2006 133: 2253-2261.
[Abstract]
[Full Text]
