Rodríguez-Marín Fernando, Pérez-Ruiz Juan M, Cejudo Francisco J
Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla and CSIC, Sevilla, Spain.
Departamento de Bioquímica Vegetal y Biología Molecular, Facultad de Biología, Universidad de Sevilla, Sevilla, Spain.
Physiol Plant. 2025 Mar-Apr;177(2):e70203. doi: 10.1111/ppl.70203.
NADPH-dependent thioredoxin reductase C (NTRC) plays a central role in redox regulation of chloroplast photosynthetic metabolism. Accordingly, Arabidopsis (Arabidopsis thaliana) NTRC-null mutants show defective photosynthetic performance and growth inhibition. Remarkably, these mutants show almost a wild-type phenotype at the seedling stage, which raises the question of whether NTRC plays different functions throughout plant development. In this work, we have addressed this issue by performing transcriptome comparisons of Arabidopsis wild-type and ntrc mutant lines at seedling and adult stages of development. In contrast with the high impact of NTRC on leaves from adult plants, the low transcriptomic differences in seedlings suggested a less relevant function of NTRC at this stage of plant development. Notably, the ntrc mutant showed transcriptomic changes resembling the response to Fe excess throughout plant development, though this response was almost unique at the seedling stage. The lack of NTRC caused altered levels of Mn, Zn, Cu, S, P, K and Na, but no significant differences in the content of Fe, as compared with the wild type. Moreover, at the seedling stage, the lack of NTRC caused hypersensitivity to Fe deficit but a protective effect in response to Fe excess, most likely due to lower ROS accumulation in the mutant seedlings. Our results reveal the different impacts of NTRC throughout plant development and identify Fe homeostasis as a process highly affected by NTRC, most notably at the seedling stage.
依赖烟酰胺腺嘌呤二核苷酸磷酸（NADPH）的硫氧还蛋白还原酶C（NTRC）在叶绿体光合代谢的氧化还原调节中起核心作用。因此，拟南芥NTRC缺失突变体表现出光合性能缺陷和生长受抑制。值得注意的是，这些突变体在幼苗期几乎呈现野生型表型，这就提出了NTRC在植物整个发育过程中是否发挥不同功能的问题。在这项研究中，我们通过对拟南芥野生型和ntrc突变体系在幼苗期和成年期发育阶段进行转录组比较来解决这个问题。与NTRC对成年植株叶片的高度影响相反，幼苗中转录组差异较小，表明NTRC在植物发育的这个阶段功能不太相关。值得注意的是，ntrc突变体在植物整个发育过程中表现出类似于对铁过量反应的转录组变化，尽管这种反应在幼苗期几乎是唯一的。与野生型相比，NTRC的缺失导致锰、锌、铜、硫、磷、钾和钠水平发生改变，但铁含量没有显著差异。此外，在幼苗期，NTRC的缺失导致对铁缺乏超敏感，但对铁过量有保护作用，这很可能是由于突变体幼苗中活性氧积累较低。我们的结果揭示了NTRC在植物整个发育过程中的不同影响，并确定铁稳态是一个受NTRC高度影响的过程，最明显的是在幼苗期。
