Minute TM Plasma Membrane Protein Isolation Kit for Plants

Plasma membrane (PM) protein accounts for a small fraction of total cellular protein in plants but performs a very critical role in plant physiology. Isolation and purification of PM protein from plant tissues have been traditionally done by sucrose density ultracentrifugation and aqueous two-phase partitioning. These relatively effective methods require ultracentrifugation and a large amount of starting material. The procedures are usually tedious and time-consuming. To overcome the shortcomings, we have developed this PM isolation kit. Plant tissues are first sensitized by buffer A, homogenized and then passed through a specialized filter cartridge that allows homogenates to pass through with a zigzag path. The cell membranes are ruptured into a range of predefined sizes during the process. Native plasma membranes are separated from a mixture of unruptured cells, nuclei, cytosol and organelles by subsequent differential centrifugation and density centrifugation without using ultracentrifugation. Due to the use of the same amount of starting material, defined centrifugal force and predefined duration in every experiment, the result is much more consistent with a high degree of PM protein enrichment. The procedure can be completed in about 1 hour.