TY - JOUR
T1 - Plant sterol metabolism. Δ7-Sterol-C5-Desaturase (STE1/DWARF7), Δ5,7-Sterol-Δ7-Reductase (DWARF5) and Δ24-Sterol-Δ24-Reductase (DIMINUTO/DWARF1) show multiple subcellular localizations in Arabidopsis thaliana (Heynh) L
AU - Silvestro, Daniele
AU - Andersen, Tonni Grube
AU - Schaller, Hubert
AU - Jensen, Poul Erik
PY - 2013/2/8
Y1 - 2013/2/8
N2 - Sterols are crucial lipid components that regulate membrane permeability and fluidity and are the precursors of bioactive steroids. The plant sterols exist as three major forms, free sterols, steryl glycosides and steryl esters. The storage of steryl esters in lipid droplets has been shown to contribute to cellular sterol homeostasis. To further document cellular aspects of sterol biosynthesis in plants, we addressed the question of the subcellular localization of the enzymes implicated in the final steps of the post-squalene biosynthetic pathway. In order to create a clear localization map of steroidogenic enzymes in cells, the coding regions of Δ7-sterol-C5-desaturase (STE1/DWARF7), Δ24-sterol-Δ24-reductase (DIMINUTO/DWARF1) and Δ5,7-sterol-Δ7-reductase (DWARF5) were fused to the yellow fluorescent protein (YFP) and transformed into Arabidopsis thaliana mutant lines deficient in the corresponding enzymes. All fusion proteins were found to localize in the endoplasmic reticulum in functionally complemented plants. The results show that both Δ5,7-sterol-Δ7-reductase and Δ24-sterol-Δ24-reductase are in addition localized to the plasma membrane, whereas Δ7-sterol-C5-desaturase was clearly detected in lipid particles. These findings raise new challenging questions about the spatial and dynamic cellular organization of sterol biosynthesis in plants.
AB - Sterols are crucial lipid components that regulate membrane permeability and fluidity and are the precursors of bioactive steroids. The plant sterols exist as three major forms, free sterols, steryl glycosides and steryl esters. The storage of steryl esters in lipid droplets has been shown to contribute to cellular sterol homeostasis. To further document cellular aspects of sterol biosynthesis in plants, we addressed the question of the subcellular localization of the enzymes implicated in the final steps of the post-squalene biosynthetic pathway. In order to create a clear localization map of steroidogenic enzymes in cells, the coding regions of Δ7-sterol-C5-desaturase (STE1/DWARF7), Δ24-sterol-Δ24-reductase (DIMINUTO/DWARF1) and Δ5,7-sterol-Δ7-reductase (DWARF5) were fused to the yellow fluorescent protein (YFP) and transformed into Arabidopsis thaliana mutant lines deficient in the corresponding enzymes. All fusion proteins were found to localize in the endoplasmic reticulum in functionally complemented plants. The results show that both Δ5,7-sterol-Δ7-reductase and Δ24-sterol-Δ24-reductase are in addition localized to the plasma membrane, whereas Δ7-sterol-C5-desaturase was clearly detected in lipid particles. These findings raise new challenging questions about the spatial and dynamic cellular organization of sterol biosynthesis in plants.
U2 - 10.1371/journal.pone.0056429
DO - 10.1371/journal.pone.0056429
M3 - Journal article
C2 - 23409184
SN - 1932-6203
VL - 8
JO - P L o S One
JF - P L o S One
IS - 2
M1 - e56429
ER -