Respiratory roots or pneumatophores

The roots of some trees and shrubs growing in saline marshes (mangrove plants) suffer from the lack of oxygen. Atmospheric air enters these roots through the minute pores of special lenticels (pneumathodes) on the exposed root tips.

TLS Online TPP Program

#Id: 8334

#XL - Q Biochemistry

Phalloidin 

isolated from Amanita phalloides, binds at the interface between subunits in F-actin, locking adjacent subunits together and preventing depolymerization.

TLS Online TPP Program

#Id: 8333

#XL - Q Biochemistry

Jasplakinolide,

a sponge toxin, enhances nucleation by binding and stabilizing actin dimers and lowering the Cc.

TLS Online TPP Program

#Id: 8332

#XL - Q Biochemistry

Latrunculin, 

a toxin secreted by sponges, binds and sequesters G-actin

TLS Online TPP Program

#Id: 8331

#XL - Q Biochemistry

Cytochalasin D, 

a fungal alkaloid, depolymerizes actin filaments by binding to the (+) end of F-actin.

TLS Online TPP Program

#Id: 8330

#XL - Q Biochemistry

TLS Online TPP Program

#Id: 8329

#XL - Q Biochemistry

Treadmilling

Because the critical concentrations for the two ends are different, at steady state the free ATP–G-actin will be intermediate between Cc+ and Cc - , so the (+)end will grow and the (-)end will lose subunits.