Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI-CONICET), Universidad Nacional de Rosario, 2000, Rosario, Argentina.
Instituto de Investigaciones Biotecnológicas, IIB-INTECH, CONICET-UNSAM, Chascomús, Argentina.
Plant Cell Rep. 2019 Aug;38(8):981-990. doi: 10.1007/s00299-019-02419-9. Epub 2019 May 7.
The ISC Fe-S cluster biosynthetic pathway would play a key role in the regulation of iron and sulfur homeostasis in plants. The Arabidopsis thaliana mitochondrial cysteine desulfurase AtNFS1 has an essential role in cellular ISC Fe-S cluster assembly, and this pathway is one of the main sinks for iron (Fe) and sulfur (S) in the plant. In different plant species it has been reported a close relationship between Fe and S metabolisms; however, the regulation of both nutrient homeostasis is not fully understood. In this study, we have characterized AtNFS1 overexpressing and knockdown mutant Arabidopsis plants. Plants showed alterations in the ISC Fe-S biosynthetic pathway genes and in the activity of Fe-S enzymes. Genes involved in Fe and S uptakes, assimilation, and regulation were up-regulated in overexpressing plants and down-regulated in knockdown plants. Furthermore, the plant nutritional status in different tissues was in accordance with those gene activities: overexpressing lines accumulated increased amounts of Fe and S and mutant plant had lower contents of S. In summary, our results suggest that the ISC Fe-S cluster biosynthetic pathway plays a crucial role in the homeostasis of Fe and S in plants, and that it may be important in their regulation.
ISC 的 Fe-S 簇生物合成途径将在植物中铁和硫稳态的调节中发挥关键作用。拟南芥的线粒体半胱氨酸脱硫酶 AtNFS1 在细胞内 ISC Fe-S 簇组装中具有重要作用，该途径是植物中铁 (Fe) 和硫 (S) 的主要吸收途径之一。在不同的植物物种中，已经报道了 Fe 和 S 代谢之间的密切关系；然而，对这两种营养物质稳态的调节还不完全清楚。在这项研究中，我们对过表达和敲低突变拟南芥植物中的 AtNFS1 进行了表征。植物表现出 ISC Fe-S 生物合成途径基因和 Fe-S 酶活性的改变。参与 Fe 和 S 摄取、同化和调节的基因在过表达植物中上调，在敲低植物中下调。此外，不同组织中的植物营养状况与这些基因活性一致：过表达系积累了更多的 Fe 和 S，而突变体植物的 S 含量较低。总之，我们的结果表明，ISC 的 Fe-S 簇生物合成途径在植物中铁和硫的稳态中起着至关重要的作用，并且可能在其调节中很重要。
