Core enzyme binds indiscriminately to any DNA. Sigma factor reduces the affinity for sequence-independent binding and confers specificity for promoters.

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

TLS Online TPP Program

#Id: 3808

#Unit 5. Developmental Biology

Newly activated genes are:

Adenylate cyclase A (ACA)

PKA

Extracellular cAMP phosphodiesterase PdsA

An intracellular cAMP phosphodiesterase RegA

TLS Online TPP Program

#Id: 3809

#Unit 5. Developmental Biology

Once all proteins are functioning, a few starving cells start to emit cAMP pulses.

TLS Online TPP Program

#Id: 3811

#Unit 5. Developmental Biology

Chemotaxis of Dictyostelium myxamoebae is a result of spiral waves of cAMP.

TLS Online TPP Program

#Id: 3817

#Unit 5. Developmental Biology

Neighboring cells respond to cAMP in two ways:

Initiate a movement toward the cAMP pulse for about a minute

Release cAMP of their own

TLS Online TPP Program

#Id: 3820

#Unit 5. Developmental Biology

The top of the mound continues to emit cAMP pulses and is pushed upwards by the movement of cells underneath