Induction of Macrocyst Germination in the Cellular Slime Mould Dictyostelium mucoroides

Abstract

~~~~Despite the usefulness of the macrocyst cycle for genetic analysis of slime mould cells, a great difficulty has been the extremely poor germination of the macrocysts. We describe culture conditions for reliable, high-frequency macrocyst germination, using Dictyostelium mucoroides 7 (Dm7) and a mutant MFl derived from it. Irradiation with relatively short-wavelength light (blue-near-UV) was particularly important for the induction of germination, and only a short period of irradiation was required to obtain a high percentage of germination. There was a critical temperature between 19 and 22 "C for efficient induction of germination; a relatively high pH, around 8-0, also favoured germination. Germination competence increased with the age of the macrocysts.

Patterning of development in Dictyostelium discoideum: factors regulating growth, differentiation, spore dormancy, and germination

“…While the cells are being engulfed, they begin to synthesize a tripartite wall to become dormant macrocysts (West and Erdos 1990). The macrocysts mature, meiosis and mitosis occur, and a mass of amoebae emerges from the cysts completing the sexual life cycle (Raper 1984;Abe and Maeda 1986). Because such alternative life cycles occur, they should also be considered in any theoretical modelling of the developmental processes in D. discoideum.…”

Cyclic AMP and Ca2+ as regulators of zygote formation in the cellular slime mold Dictyostelium mucoroides

“…The macrocyst thus formed germinates to release some amoebae, and each of them enters a new life cycle. A method for inducing a high germination rate has been explored by Abe and Maeda [2]. Macrocysts are formed homothallically in Dm7 [28], while heterothallically in D. discoideum [20].…”

Induction of Heterothallic and Homothallic Zygotes in Dictyostelium discoideum by Ethylene

“…The macrocyst thus formed germinates to release some amoebae and to complete the life cycle. Induction of a high germination rate has been explored by Abe and Maeda (1).…”