Actin polymerization

Cell migration is initiated by a stimulus that activates a set of signaling pathways leading to cellular polarization and a rapid reorganization of actin filaments and microtubules. Actin is therefore one of key players of cell migration.

How can I identify and characterize actin polymerization/depolymerization effectors?

With the Actin Polymerization Biochem Kit™

The Actin Polymerization Biochem Kit™ (Cat nr BK003) is based upon the increase of fluorescence of pyrene-conjugated actin that occurs during the polymerization. The enhanced fluorescence that occurs when pyrene G-actin (monomer) forms pyrene F-actin can be measured in a fluorimeter to follow polymerization over time.

Also, by using preformed pyrene F-actin, it is possible to follow depolymerization.

Both cell/tissue extracts and purified proteins can be added to the reaction mixture to identify their effect on actin polymerization.

Discover the kit ( Cat nr BK003) and its contents here.

Application example: characterization of an actin binding protein

The Actin Polymerization Biochem Kit™ was used to study the effects of Arp2/3  and the VCA domain of WASP on actin polymerization rates. The Arp2/3 complex is an actin filament nucleator but has low nucleating/polymerizing activity on its own. The VCA domain of WASP is an activator of the Arp2/3 complex. Hence, when the Arp2/3 complex is mixed with the WASP VCA domain, these two exert a potent actin polymerizing activity:

 

 

Actin polymerization stimulated by Arp2/3 complex and the VCA domain of WASP. Actin polymerization was measured using kit Cat nr BK003. The addition of Arp2/3 complex or the VCA domain alone to actin has minimal effects on actin polymerization, while the combination of Arp2/3 and the VCA domain strongly stimulates the rate of actin polymerization.