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Updated: Aug 15, 2026
07:48
Investigating the Function of Coronin A in the Early Starvation Response of Dictyostelium discoideum by Aggregation Assays
Published on: June 18, 2016
A secreted factor represses cell proliferation in Dictyostelium
Debra A Brock1, Richard H Gomer
1Howard Hughes Medical Institute and Department of Biochemistry and Cell Biology, MS-140, Rice University, 6100 South Main Street, Houston, TX 77005-1892, USA.
Development (Cambridge, England)
|September 24, 2005
Summary
Dictyostelium cells secrete a novel protein, AprA (autocrine proliferation repressor), that acts as a chalone to inhibit cell proliferation. Deletion of AprA leads to faster growth and abnormal development, suggesting its crucial role in regulating cell growth and differentiation.
Area of Science:
- Cell Biology
- Developmental Biology
- Biochemistry
Background:
- Chalones are hypothesized factors that limit cell proliferation, but specific molecular identities are often unknown.
- Understanding endogenous regulators of cell growth is crucial for developmental processes.
Purpose of the Study:
- To identify and characterize the molecular factor responsible for autocrine proliferation control in Dictyostelium.
- To investigate the function of the identified factor in cell proliferation and development.
Main Methods:
- Gene knockout and overexpression in Dictyostelium discoideum.
- Protein purification via immunoprecipitation.
- Cell proliferation assays.
- Analysis of developmental structures and spore formation.
Main Results:
- A 60 kDa protein, AprA (autocrine proliferation repressor), was identified as a secreted factor.
- AprA-null cells exhibited faster proliferation, while AprA-overexpressing cells showed slower proliferation.
- Purified AprA inhibited proliferation of both wild-type and aprA-null cells.
- AprA-null cells displayed increased multinucleation and defects in spore formation during starvation.
Conclusions:
- AprA functions as a chalone, regulating Dictyostelium cell proliferation.
- AprA plays a role in preventing multinucleation and promoting efficient spore production during development.
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