What would happen to treadmilling of actin if you add phallo

What would happen to treadmilling of actin if you add phalloidin to a cell?

Solution

Treadmilling: - This phenomenon occurs in cellular filaments, cytoskeletal filaments especially in microtubule and actin filament. Actually in treadmilling there will be elongation of one end by addition of subunits and removal of subunits from opposite end which cause the movement in substitution side. Removal and addition of subunits on ends of filament cause the movements.

Phalloidin is toxic compoud. When it added to cell it will binds with actin, and prevent the depolymerization and cause the poisoning in cell. It is a heptapeptide,which binds with actin filaments strongly than monomer subunit of actin, After that the rate of dissociation from one end will decrease which inhibit the actin movement. In normal condition dissociation stablize the the actin filament by depolymerization. Phalloidin increase the rate of polymerization of actin subunit. In opposite it reduce rate of dissociation.