U-Blot™ Plant Plasma Membrane Protein Isolation Kit

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 or aqueous two-phase partitioning. These methods, while relatively effective, require ultracentrifugation and 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 pass 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 size during the process. Native plasma membranes are separated from a mixture of un-ruptured cells, nuclei, cytosol and organelles by subsequent differential centrifugation and density centrifugation without using ultracentrifugation. Due to the use of same amount of starting material, defined centrifugal force and pre-defined duration in every experiment, the result is much more consistent with high degree of PM protein enrichment. The procedure can be completed in about 1h.