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

基因模型植物拟南芥的基因组编码超过100种蛋白质，这些蛋白质需要铁硫（FeS）簇辅因子才能发挥其生物学功能，例如在光合作用、呼吸作用和核酸代谢中。植物体内存在三种FeS簇组装途径，分别在叶绿体、线粒体和细胞质中组装。作为固着生物，它们必须在波动和非最佳环境条件下有效地保护FeS蛋白的生物合成，例如在活性氧或过量干扰金属的存在下。为了研究这是如何实现的，我们分析了FeS依赖性和其他金属蛋白在不同细胞隔室的生物起源的昼夜动态，通过使用全基因组翻译组测序（ribo-seq）作为代理。这是结合金属和低分子量螯合剂浓度，亚细胞金属分布和酶活性的主要钼辅因子（Moco-）和FeS依赖性蛋白质的昼夜动态分析。我们比较野生型植物与植物表现出缺陷的三个FeS簇组装途径，揭示了可能的依赖，和调节作用，亚细胞FeS簇组装金属稳态和金属蛋白的生物合成。我们的研究结果可以作为未来战略的基础，以优化生物能源生产和农业施肥方案。

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.