Purification of rabbit lacrimal gland plasma membranes by aqueous two-phase affinity partitioning

摘要

We describe the purification of lacrimal gland plasma membralleS by affinity partitioning using a two-phase system containing polyethylene glycol and dextran in which wheat germ agglutinin conjugated to dextran is used as affinity ligand. When partitioning a microsomal fraction. the plasma membrane marker 5'-nucleotidase was obtained in the affinity ligand-containing bottom phase. whereas the endoplasmic reticulum marker NADH-ferricyanide reductase remained in the top phase. The affinity partitioning behaviour of components involved in exocytosis and cellular signalling was also examined.