Stalk cell differentiation without polyketides in the cellular slime mold.
Polyketides induce prestalk cell differentiation in Dictyostelium. In the double-knockout mutant of the SteelyA and B polyketide synthases, most of the pstA cells-the major part of the prestalk cells-are lost, and we show by whole mount in situ hybridization that expression of prestalk genes is also reduced. Treatment of the double-knockout mutant with the PKS inhibitor cerulenin gave a further reduction, but some pstA cells still remained in the tip region, suggesting the existence of a polyketide-independent subtype of pstA cells. The double-knockout mutant and cerulenin-treated parental Ax2 cells form fruiting bodies with fragile, single-cell layered stalks after cerulenin treatment. Our results indicate that most pstA cells are induced by polyketides, but the pstA cells at the very tip of the slug are induced in some other way. In addition, a fruiting body with a single-cell layered, vacuolated stalk can form without polyketides.
a Graduate School of Science and Technology , Sophia University , Tokyo Japan.
Yukie G
YG
Sato
b Department of Cellular and Molecular Medicine, Centro de Investigaciones Biológicas , Consejo Superior de Investigaciones Científicas , Madrid , Spain.
Teresa
T
Suarez
c Faculty of Science and Technology , Sophia University , Tokyo , Japan.
Tamao
T
Saito
D002454:Cell Differentiation / Q000235:genetics*; D002569:Cerulenin / Q000494:pharmacology; D004023:Dictyostelium / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism / Q000648:ultrastructure; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015870:Gene Expression; D055786:Gene Knockout Techniques; D017403:In Situ Hybridization; D007527:Isoenzymes / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D048630:Polyketide Synthases / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D061065:Polyketides / Q000378:metabolism* / Q000494:pharmacology; D015800:Protozoan Proteins / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism
D004791:Enzyme Inhibitors; D007527:Isoenzymes; D061065:Polyketides; D015800:Protozoan Proteins; D002569:Cerulenin; D048630:Polyketide Synthases
cerulenin; differentiation; polyketide synthase; prestalk