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Updated: Jun 6, 2026

Genetic Engineering of Dictyostelium discoideum Cells Based on Selection and Growth on Bacteria
Published on: January 25, 2019
Sex determination in the social amoeba Dictyostelium discoideum
Gareth Bloomfield1, Jason Skelton, Alasdair Ivens
1Medical Research Council Laboratory of Molecular Biology, Hills Road, Cambridge CB2 0QH, UK. garethb@mrc-lmb.cam.ac.uk
Abstract:
The genetics of sex determination remain mysterious in many organisms, including some that are otherwise well studied. Here we report the discovery and analysis of the mating-type locus of the model organism Dictyostelium discoideum. Three forms of a single genetic locus specify this species' three mating types: two versions of the locus are entirely different in sequence, and the third resembles a composite of the other two. Single, unrelated genes are sufficient to determine two of the mating types, whereas homologs of both these genes are required in the composite type. The key genes encode polypeptides that possess no recognizable similarity to established protein families. Sex determination in the social amoebae thus appears to use regulators that are unrelated to any others currently known.
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