The TIR1 protein binds to the SCF complex and is then headed for degradation after binding to these entities.
The TIR1 protein binds to the SCF complex and is then headed for degradation after binding to these entities. PGP and PIN are proteins involved in the transport of these molecules. Their transport also involves a decrease in the pH of the cell, which induces the activation of expansins. Excess concentration of these molecules can induce Ethylene synthesis, which causes leaf abscission. Indole-3-acetic acid is an important member of this class of molecules, which play a significant role in apical dominance. For 10 points, identify these plant hormones which are best known for their influence in phototropism and geotropism. 
The TIR1 protein binds to the SCF complex and is then headed for degradation after binding to these entities.
auxins