A cell-counting factor regulating structure size in Dictyostelium.

D A Brock; R H Gomer

doi:10.1101/gad.13.15.1960

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A cell-counting factor regulating structure size in Dictyostelium.

D A Brock·R H Gomer

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Abstract

Developing Dictyostelium cells form large aggregation streams that break up into groups of 0.2 x 10(5) to 1 x 10(5) cells. Each group then becomes a fruiting body. smlA cells oversecrete an unknown factor that causes aggregation streams to break up into groups of approximately 5 x 10(3) cells and thus form very small fruiting bodies. We have purified the counting factor and find that it behaves as a complex of polypeptides with an effective molecular mass of 450 kD. One of the polypeptides is a 40-kD hydrophilic protein we have named counting. In transformants with a disrupted counting gene, there is no detectable secretion of counting factor, and the aggregation streams do not break up, resulting in huge (up to 2 x 10(5) cell) fruiting bodies.

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Amino Acid Sequence Animals Base Sequence Cell Aggregation Cell Count Cloning, Molecular Culture Media, Conditioned Dictyostelium Molecular Sequence Data Molecular Weight Mutation Phenotype Protein Sorting Signals Protozoan Proteins RNA, Messenger Sequence Analysis Signal Transduction Journal Article Research Support, Non-U.S. Gov't

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D A Brock, R H Gomer. 1999-08-01. A cell-counting factor regulating structure size in Dictyostelium.. https://doi.org/10.1101/gad.13.15.1960

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