Leong Bryan J, Hurney Steven, Fiesel Paul, Anthony Thilani M, Moghe Gaurav, Jones Arthur Daniel, Last Robert L
Department of Plant Biology Michigan State University East Lansing Michigan USA.
Present address: Horticultural Sciences Department University of Florida Gainesville Florida USA.
Plant Direct. 2022 Jun 18;6(6):e415. doi: 10.1002/pld3.415. eCollection 2022 Jun.
Plants make a variety of specialized metabolites that can mediate interactions with animals, microbes, and competitor plants. Understanding how plants synthesize these compounds enables studies of their biological roles by manipulating their synthesis in vivo as well as producing them in vitro. Acylsugars are a group of protective metabolites that accumulate in the trichomes of many Solanaceae family plants. Acylinositol biosynthesis is of interest because it appears to be restricted to a subgroup of species within the Solanum genus. Previous work characterized a triacylinositol acetyltransferase involved in acylinositol biosynthesis in the Andean fruit plant (lulo or naranjilla). We characterized three additional trichome expressed enzymes and found that virus-induced gene silencing of each caused changes in acylinositol accumulation. pH was shown to influence the stability and rearrangement of the product of ASAT1H and could potentially play a role in acylinositol biosynthesis. Surprisingly, the in vitro triacylinositol products of these enzymes are distinct from those that accumulate . This suggests that additional enzymes are required in acylinositol biosynthesis. These characterized enzymes, nonetheless, provide opportunities to test the biological impact and properties of these triacylinositols in vitro.
植物会产生多种特殊的代谢产物，这些产物能够介导植物与动物、微生物以及竞争性植物之间的相互作用。了解植物如何合成这些化合物，有助于通过在体内操纵其合成以及在体外进行生产，来研究它们的生物学作用。酰基糖是一类保护性代谢产物，在许多茄科植物的毛状体中积累。酰基肌醇的生物合成备受关注，因为它似乎仅限于茄属中的一个物种亚群。先前的研究对参与安第斯水果植物（卢洛或纳兰吉亚）中酰基肌醇生物合成的一种三酰基肌醇乙酰转移酶进行了表征。我们对另外三种在毛状体中表达的酶进行了表征，发现对每种酶进行病毒诱导的基因沉默都会导致酰基肌醇积累的变化。研究表明，pH值会影响ASAT1H产物的稳定性和重排，并且可能在酰基肌醇生物合成中发挥作用。令人惊讶的是，这些酶的体外三酰基肌醇产物与积累的产物不同。这表明酰基肌醇生物合成还需要其他酶。尽管如此，这些已表征的酶为在体外测试这些三酰基肌醇的生物学影响和特性提供了机会。
