Identification of sterol-containing domains in vacuolar membranes by confocal microscopy

Abstract

Sterol-containing domains in the tonoplast of beet root cells were identified by confocal microscopy with a membrane probe filipin. The presence of sterol-containing domains in the tonoplast was confirmed using methyl-β-cyclodextrin. Sterol-containing domains with separate small intensely fluorescing sterol-enriched sites were found in the vacuolar membrane; these sites can be attributed to raft structures. It was shown that sterol content in the isolated rafts can be assessed by confocal microscopy. β-Sitosterol, stigmasterol, α-tocopherol, and cholesterol were identified among the sterols of the isolated rafts.