Product Uses Include

• Fluorescent staining of actin filaments in fixed tissue sections and tissue culture cells preparations.Note: Unlike many actin antibodies, Acti-stain? 555 phalloidin binds only to F-actin resulting in low background fluorescence.  Furthermore, actin staining is not appreciably different between species.

• Preparation of stabilized fluorescent actin filaments in vitro.

Actin staining is very useful in determining the structure and function of the cytoskeleton in living a nd fixed cells. The actin cytoskeleton is a very dynamic and labile structure in the living cell, but it can be fixed with paraformaldehyde prior to probing or staining for actin structures. 

Material

Phalloidin is a seven amino acid peptide toxin from the mushroom Amanita phalloides, which binds specifically and with high affinity (Kd 20 nM) to the polymerized form of actin (F-actin).  Phalloidin lowers the critical concentration of actin polymerization to less than 1 μg/ml, thereby acting as a polymerization enhancer. Phalloidin has been labeled with a proprietary red fluorescent dye which allows it to be used to stain actin filaments in tissue cultured cells and tissue sections (1, see Figure 1)?and cell-free preparations.  Acti-stain? 555 phalloidin-labeled actin filaments retain many functional characteristics of unlabeled actin including their ability to interact with myosin.  Actin-stain? 555 phalloidin is supplied as a red solid. 

Note: Phalloidin is toxic and must be handled with care (LD50 human = 2mg/Kg).