Functions of sterols in plants

Abstract

Sterols have at least three functions in animals: they may act as precursors of other steroids, as hormones and as membrane components. The author advances the hypothesis that sterols have similar functions in plants.

Sterol Accumulation and Composition in Developing Zea mays L. Kernels

“…However, Heftman (6) has suggested that sitosterol may function as a reserve supply for other phytosterols. Cholesterol has been described as a key intermediate of other plant steroids (6) and Kemp and Mercer (10) found the esterified cholesterol to be the major sterol of the nuclear and chloroplastic fraction in maize shoots.…”

Assessment of lipid compounds and phosphorus in mangrove sediments of Santa Catarina Island, SC, Brazil

“…10 C 28 and C 29 desmethyl sterols in sediments that are believed to originate predominantly from vascular plants include: campesterol (24-methyl-5-cholesten-3β-ol), β-sitosterol (24α-ethyl-5-cholesten-3β-ol), and stigmasterol (24α-ethyl-5, (22E)-cholestadien-3β-ol). 11 In spite of these compounds being commonly used as tracers of continentally derived organic matter inputs into marine systems, inferences drawn from sterol distributions regarding terrigenous vs. marine sources of organic matter must be made with caution. 10,12,13 Animals are thought to be unable to synthesize sterols containing an alkyl chain at the C-24 position.…”

Effects of Free Sterols, Steryl Ester, and Steryl Glycoside on Membrane Permeability

“…However, in this same study the steryl glycosides were very similar in composition to the free sterols, making this sterol form the more likely for translocation. But it is also possible that the steryl esters and/or steryl glycosides are precursors to other steroids which may act as plant hormones (9,17).…”