Pitfall traps set into the ground catch wandering species such as beetles and spiders. These have rain covers to prevent the animals from drowning

 

TLS Online TPP Program

#Id: 3802

#Unit 5. Developmental Biology

During growth, unicellular D. discoideum monitor their cell density relative to that of their bacterial food source by secreting a glycoprotein called prestarvation factor at a constant rate.

TLS Online TPP Program

#Id: 3803

#Unit 5. Developmental Biology

When the ratio of PSF relative to that of bacteria exceeds a certain threshold, cells stop proliferating and initiate the expression of genes that are required for their aggregation.

TLS Online TPP Program

#Id: 3804

#Unit 5. Developmental Biology

Early on during aggregation, gene expression requires the activity of cAMP-dependent protein kinase.

TLS Online TPP Program

#Id: 3805

#Unit 5. Developmental Biology

High PSF to food ratio is upregulate the translation of the PKA catalytic subunit PKA-C.

TLS Online TPP Program

#Id: 3806

#Unit 5. Developmental Biology

A second glycoprotein secreted during starvation is CMF (conditioned medium factor)

TLS Online TPP Program

#Id: 3807

#Unit 5. Developmental Biology

CMF stimulates gene expression in parallel with PSF, and both signals potentiate cAMP signalling by inducing genes involved in cAMP synthesis and detection