First published online August 24, 2007
Development 134, 1805e (2007)
© The Company of Biologists Limited
Dicty culmination: a breath of ancient air
The soil amoeba Dictyostelium is an excellent model system in
which to study how environmental signals regulate development. Starvation
induces the amoebae to aggregate into a slug, which migrates to the soil
surface. Here it `culminates', forming a fruiting body of spores and stalk
cells. Culmination is O2-dependent and, on
p. 3349, West and
co-workers reveal that the enzyme prolyl 4-hydroxylase-1 (P4H1) acts as an
O2 sensor during this stage of Dictyostelium development.
Culmination normally requires O2 levels above 10%. But, the
researchers show, disruption of the P4H1 gene increases this requirement so
that culmination is blocked at ambient O2 levels. By contrast,
overexpression of P4H1 reduces the O2 requirement of culmination to
below 5%. Because P4H1 is an orthologue of the prolyl hydroxlases that sense
O2 levels in animals, the researchers suggest that it functions as
part of an ancient mechanism for O2 sensing that predates the
evolution of animals and that, in Dictyostelium, regulates
culmination.
Related articles in Development:
- Prolyl 4-hydroxylase-1 mediates O2 signaling during development of Dictyostelium
- Christopher M. West, Hanke van der Wel, and Zhuo A. Wang
Development 2007 134: 3349-3358.
[Abstract]
[Full Text]
