First published online September 28, 2005
Development 132, 2004e (2005)
© The Company of Biologists Limited
Crowd control the Dicty way
Dictyostelium discoideum spends most of its life as vegetative
amoebae, but, when food becomes limiting, the amoebae stop dividing, aggregate
and develop into a mass of spores supported by a stalk. Unexpectedly, Brock
and Gomer have now found that growing Dictyostelium cells secrete a
protein (called AprA, for autocrine proliferation repressor) that represses
their proliferation (see p.
4553). They show that
aprA-null cells proliferate faster than wild-type cells, and that
purified AprA slows the proliferation of both wild-type and aprA-null
cells. However, upon starvation, aprA-null cells make spores less
efficiently than wild-type cells do. Overall, these results indicate that
there is an evolutionary advantage to slowing proliferation when
Dictyostelium cells get crowded. In addition, the researchers suggest
that AprA may be part of a Dictyostelium chalone–in metazoa,
chalones are secreted autocrine factors thought to control organ size.
Related articles in Development:
- A secreted factor represses cell proliferation in Dictyostelium
- Debra A. Brock and Richard H. Gomer
Development 2005 132: 4553-4562.
[Abstract]
[Full Text]
