Institut de Biologie Moléculaire des Plantes du Centre National de la Recherche Scientifique, IBMP-CNRS-UPR2357, Université de Strasbourg, 28 Rue Goethe, F-67083 Strasbourg Cedex, France.
Prog Lipid Res. 2012 Apr;51(2):95-148. doi: 10.1016/j.plipres.2011.12.001. Epub 2011 Dec 14.
When compared to other organisms, plants are atypical with respect to isoprenoid biosynthesis: they utilize two distinct and separately compartmentalized pathways to build up isoprene units. The co-existence of these pathways in the cytosol and in plastids might permit the synthesis of many vital compounds, being essential for a sessile organism. While substrate exchange across membranes has been shown for a variety of plant species, lack of complementation of strong phenotypes, resulting from inactivation of either the cytosolic pathway (growth and development defects) or the plastidial pathway (pigment bleaching), seems to be surprising at first sight. Hundreds of isoprenoids have been analyzed to determine their biosynthetic origins. It can be concluded that in angiosperms, under standard growth conditions, C₂₀-phytyl moieties, C₃₀-triterpenes and C₄₀-carotenoids are made nearly exclusively within compartmentalized pathways, while mixed origins are widespread for other types of isoprenoid-derived molecules. It seems likely that this coexistence is essential for the interaction of plants with their environment. A major purpose of this review is to summarize such observations, especially within an ecological and functional context and with some emphasis on regulation. This latter aspect still requires more work and present conclusions are preliminary, although some general features seem to exist.
与其他生物相比，植物在异戊二烯生物合成方面是非典型的：它们利用两种不同的、分别分隔的途径来构建异戊二烯单位。这些途径在细胞质和质体中的共存可能允许合成许多重要的化合物，这对一个固着生物来说是必不可少的。虽然已经证明了各种植物物种之间存在跨膜的底物交换，但最初看来，由于细胞质途径（生长和发育缺陷）或质体途径（色素漂白）的失活而导致的强表型的互补缺失似乎令人惊讶。已经分析了数百种异戊二烯来确定它们的生物合成起源。可以得出结论，在被子植物中，在标准生长条件下，C₂₀-植基部分、C₃₀-三萜类和 C₄₀-类胡萝卜素几乎完全在分隔的途径中合成，而其他类型的异戊二烯衍生分子的混合起源则很普遍。这种共存似乎对植物与环境的相互作用是必不可少的。本文综述的主要目的是总结这些观察结果，特别是在生态和功能背景下，并对调控进行一些强调。尽管存在一些普遍特征，但这一方面仍需要更多的工作，目前的结论还只是初步的。
