ABSTRACT

Formate is produced, in plants, by various biochemical pathways and it is degraded by Formate Dehydrogenase FDH, in presence of NAD⁺, into CO₂ and NADH. FDH has been proposed as one of the enzymes regulating molybdenum (Mo) and iron (Fe) homeostasis. Here we explored the impact of FDH perturbation on Mo and Fe plant nutritional status and FDH relevance on the plant responses against abiotic stresses, by using in silico and experimental approaches. The characterization of different Arabidopsis thaliana and Nicotiana tabacum FDH transgenic lines suggests that FDH promoter activity is dependent on both Mo and Fe nutritional supply and that FDH overexpression alters Mo concentrations in seeds and Fe concentration in seeds, leaves and stems. Also, FDH overexpression delays the dark-induced senescence whereas the lack of FDH accelerates its progression. FDH is therefore a multifaceted enzyme with impact on Mo and Fe homeostasis and regulation of dark-induced senescence.

摘要

甲酸酯在植物中通过各种生化途径产生，在NAD ⁺存在下，甲酰胺脱氢酶FDH将其降解为CO ₂和NADH。已经提出了FDH作为调节钼（Mo）和铁（Fe）稳态的酶之一。在这里，我们通过计算机模拟和实验方法探讨了FDH摄动对Mo和Fe植物营养状况的影响以及FDH对植物对非生物胁迫的响应的相关性。不同拟南芥和烟草的表征FDH转基因品系表明FDH启动子的活性取决于Mo和Fe的营养供应，并且FDH的过表达改变了种子中Mo的浓度以及种子，叶和茎中Fe的浓度。同样，FDH的过表达延迟了黑暗诱导的衰老，而缺乏FDH则加速了它的进程。因此，FDH是一种多方面的酶，可影响Mo和Fe的体内稳态并调节黑暗诱导的衰老。