Goto Mina, Nemoto Takanari, Sakoda Kazuma, Sakurai Atsushi, Imamura Sousuke, Masuda Shinji
Department of Life Science and Technology, Institute of Science Tokyo, Yokohama, Japan.
Space Environment and Energy Laboratories, NTT Corporation, Musashino-shi, Japan.
Front Plant Sci. 2025 Jan 13;15:1524665. doi: 10.3389/fpls.2024.1524665. eCollection 2024.
To enhance plant biomass production under low nitrogen conditions, we employed a method to artificially and temporarily accumulate the bacterial second messenger, guanosine tetraphosphate (ppGpp), to modify plastidial or mitochondrial metabolism. Specifically, we fused a chloroplast or mitochondrial transit-peptide to the N-terminus of the bacterial ppGpp synthase YjbM, which was conditionally expressed by an estrogen-inducible promoter in . The resulting recombinant plants exhibited estrogen-dependent ppGpp accumulation in chloroplasts or mitochondria and showed reduced fresh weight compared to wild type (WT) plants when grown on agar-solidified plates containing a certain amount of estrogen. This finding aligns with the previous study indicating that plastidial ppGpp levels can influence plant biomass production. When the recombinant plants were grown in the soil with estrogen and low nitrogen-containing water at specific time intervals, they exhibited greater fresh weight than WT plants. These results suggest that the conditional accumulation of ppGpp in not only chloroplasts, but also in mitochondria can lead to improved plant biomass production in soil with low nitrogen applications.
为了提高低氮条件下的植物生物量产量，我们采用了一种方法，人工地、暂时地积累细菌第二信使鸟苷四磷酸（ppGpp），以改变质体或线粒体的代谢。具体而言，我们将叶绿体或线粒体转运肽与细菌ppGpp合酶YjbM的N端融合，该合酶由雌激素诱导型启动子在……中进行条件表达。所得的重组植物在叶绿体或线粒体中表现出雌激素依赖性的ppGpp积累，并且在含有一定量雌激素的琼脂固化平板上生长时，与野生型（WT）植物相比鲜重降低。这一发现与先前的研究一致，该研究表明质体中的ppGpp水平可影响植物生物量产量。当重组植物在特定时间间隔用雌激素和低氮水浇灌种植于土壤中时，它们表现出比WT植物更大的鲜重。这些结果表明，ppGpp不仅在叶绿体中，而且在线粒体中的条件性积累都可导致在低氮土壤中种植时植物生物量产量提高。
