Sterols found in all eukaryotic organisms are membrane components which regulate the fluidity and the permeability of phospholipid bilayers. Certain sterols in minute amounts, such as campesterol in Arabidopsis thaliana, are precursors of oxidized steroids acting as growth hormones collectively named brassinosteroids. The crucial importance of brassinosteroids upon growth and development has been established through the study of a set of dwarf mutants affected in brassinosteroid synthesis or perception. Some of these dwarfs are, in fact, deficient in the final steps of sterol biosynthesis and their developmental phenotypes are primarily caused by a depletion in the sterol precursor for brassinosteroids. Recently, the characterization of genes encoding sterol biosynthetic enzymes and the isolation of novel plant lines affected in the expression of those genes, either by insertional or classical mutagenesis, overexpression or cosuppression, have shed new light on the involvement of sterols in biological processes such as embryonic development, cell and plant growth, and fertility, which will be presented and discussed in this review article.

中文翻译：

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固醇在植物生长发育中的作用。

在所有真核生物中发现的甾醇是调节磷脂双层的流动性和渗透性的膜成分。某些微量的固醇，例如拟南芥中的菜油甾醇，是氧化类固醇的前体，它们充当生长激素，统称为油菜素类固醇。通过研究一系列受油菜素类固醇合成或感知影响的矮化突变体，已经确定了油菜素类固醇对生长和发育的至关重要。实际上，其中一些矮人在固醇生物合成的最后步骤中是不足的，它们的发育表型主要是由油菜素固醇的固醇前体的消耗引起的。最近，