Diurnal Dynamics in the Biogenesis of Iron-Sulfur Cluster and other Metalloproteins of Plants in Dependence on Cluster Assembly

遗传模式植物拟南芥的基因组编码100多种蛋白质，这些蛋白质需要铁硫簇辅助因子来发挥其生物学功能，例如在光合作用、呼吸和核酸代谢中。植物具有三条组装FeS簇的细胞途径，分别位于叶绿体、线粒体和细胞质中。作为固着生物，它们必须有效地保护FeS蛋白在波动和非最佳环境条件下的生物发生，例如在存在活性氧物种或过量干扰金属的情况下。为了检验这是如何实现的，我们使用全基因组翻译组测序(RIBO-SEQ)作为替代，分析了不同细胞间隔中依赖FeS和其他金属蛋白的生物发生的日动态。这结合了对金属和低分子量螯合剂浓度、亚细胞金属分布以及主要钼辅因子(MOCO-)和FeS依赖蛋白的酶活性的日动态分析。我们比较了野生型植物和在三个FES簇组装途径中每一个都表现出缺陷的植物，以揭示亚细胞FES簇组装对金属动态平衡和金属蛋白生物合成的可能依赖和调节作用。我们的结果可以作为未来优化生物能源生产和农业施肥计划的战略的基础。

The genome of the genetic model plant Arabidopsis thaliana encodes more than 100 proteins that require iron-sulfur (FeS) cluster cofactors for their biological function, for example in photosynthesis, respiration and nucleic acid metabolism. Plants possess three cellular pathways of FeS cluster assembly in chloroplasts, mitochondria and the cytosol, respectively. As sessile organisms, they must efficiently protect the biogenesis of FeS proteins under fluctuating and non-optimal environmental conditions, for example in the presence of reactive oxygen species or an excess of interfering metals. To examine how this is accomplished, we analyze the diurnal dynamics in the biogenesis of FeS-dependent and other metalloproteins in different cellular compartments by using genome-wide translatome sequencing (ribo-seq) as a proxy. This is combined with an analysis of the diurnal dynamics of metal and low-molecular-weight chelator concentrations, sub-cellular metal distribution and enzyme activities of major molybdenum cofactor(Moco-) and FeS-dependent proteins. We compare wild-type plants with plants exhibiting defects in each of the three FeS cluster assembly pathways to reveal a possible dependence on, and regulatory roles of, subcellular FeS cluster assembly for metal homeostasis and metalloprotein biosynthesis. Our results can serve as a basis for future strategies to optimize bioenergy production and agricultural fertilization schemes.