Product uses include

  • Positive control to study the activity of F-actin capping and cutting proteins
  • Investigation of the effect of actin-binding proteins (ABPs) on actin dynamics

Product Name: Homo sapiens Recombinants

Material

Gelsolin protein has been purified from E.coli expressing 6xHIS-tagged recombinant human gelsolin (plasma isoform). Gelsolin belongs to a class of actin cleavage and protection proteins called class I F-actin protection proteins. Each of these class I proteins contain a series of conserved 125-150 amino acid repeat motifs. Gelsolin is characterized by the presence of six repeat motifs, three of which are actin-binding domains.

Gelsolin exerts a powerful regulatory role on the length of the actin filament and its activity can be modulated by Ca2+ levels, pH, polyphosphoinositides and post-translational modification. Plasma gelsolin contains an additional 25aa leader sequence compared to the cytoplasmic isoform. Gelsolin is supplied as a white lyophilised powder. After reconstitution with nanopure water, the protein will be in the following buffer: 10 mM Tris pH 7.5, 10 mM NaCl, 0.1 mM MgCl2, 1% (w/v) sucrose, and 0.1% dextran (w/w). Lyophilized protein is stable at 4°C desiccated (<10% humidity) for 6 months.

Purity

Protein purity is determined by scanning densitometry of Coomassie blue-stained protein on a 4-20% gradient polyacrylamide gel. The gelsolin protein is greater than 90% pure (see Figure 1) and operates at approximately 95 kDa (due to the leader sequence and the 6xHIS tag).

Biological activity

The biological activity of gelsolin is determined in an F-actin cleavage assay. F-actin is incubated with gelsolin and the reaction products are centrifuged at 100,000 x g for 1 h. The ratio of actin in the supernatant (G-actin) versus pellet (F-actin) is compared to a control reaction without gelsolin. Strict quality control ensures that gelsolin (2 µg) can solubilize 70-80% of F-actin (5 µg) within five minutes.