S phase cyclin-CDK accumulates in late G1 , they are immediately inactivated by binding of a CKI called Sic1

TLS Online TPP Program

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#Unit 6. System Physiology – Plant

Several compounds have been synthesized that can act as auxin transport inhibitors (ATIs), including

NPA (1-Nnaphthylphthalamic acid)

TIBA (2,3,5-triiodobenzoic acid)

CPD( 2- carboxyphenyl-3-phenylpropane-1,3- dione)

NOA ( naphthoxyacetic acid)

Gravacin

TLS Online TPP Program

#Id: 7522

#Unit 6. System Physiology – Plant

NPA, TBA, CPD and gravacin are auxin efflux

inhibitors

NOA is an auxin influx inhibitor

AEIs can interfere with the trafficking of the plasma membrane proteins to which they bind, apparently by altering protein-preotein interactions.

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#Id: 7523

#Unit 6. System Physiology – Plant

Cytochalasin D, an inhibitor of actin polymerization, also inhibits AUXIN efflux

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#Id: 7524

#Unit 6. System Physiology – Plant

Auxin-induced proton extrusion acidifies the cell wall and increases cell extension Auxin increase the rate of proton extrusion (wall acidification), and the kinetics of proton extrusion should closely match those of auxin-induced growth.

TLS Online TPP Program

#Id: 7525

#Unit 6. System Physiology – Plant

TLS Online TPP Program

#Id: 7526

#Unit 6. System Physiology – Plant

AUXIN SIGNAL TRANSDUCTION PATHWAYS