Question

Explain what type of signaling the amoeba Dictyostelium discoideum uses and for which goal

Answer 1

Ans:-) Continuous signalling is necessary for communication among the cells. Intracellular signals are used in plants and animals for communication. The signals are also used in Dictyostelium discoideum.

In these, solitary cells aggregate together to form multicellular structure. Many of signals are recognised by surface receptors that are seven transmembrane proteins. These proteins are coupled with G proteins which pass signal on to the components within cytoplasm.

The amoeba cells have to judge sufficient density of cell has reached to warrant transition from growth to differentiation. They have to recognise when exogenous nutrients become limiting and then initiate development.

After few hours they signal each other with cAMP which regulate gene expression and direct chemotactic aggregation.

They then recognise because they develop only when they are surrounded by close kin.

After all this, cell diverge into 2 cell types :- prestalk and prespore cells. Both of these communicate each other to form wel developed fruiting bodies.

In this signaling is necessary in Dictyostelium discoideum for proper development.