Miyazaki Sho, Jiang Kai, Kobayashi Masatomo, Asami Tadao, Nakajima Masatoshi
a Department of Applied Biological Chemistry , The University of Tokyo , Tokyo , Japan.
b BioResource Center, RIKEN , Tsukuba , Japan.
Biosci Biotechnol Biochem. 2017 Nov;81(11):2152-2159. doi: 10.1080/09168451.2017.1381018. Epub 2017 Oct 11.
Helminthosporol was isolated from a fungus, Helminthosporium sativum, as a natural plant growth regulator in 1963. It showed gibberellin-like bioactivity that stimulated the growth of the second leaf sheath of rice. After studying the structure-activity relationship between the compound and some synthesized analogs, it was found that helminthosporic acid (H-acid) has higher gibberellin-like activity and chemical stability than helminthosporol. In this study, we showed that (1) H-acid displays gibberellin-like activities not only in rice but also in Arabidopsis, (2) it regulates the expression of gibberellin-related genes, (3) it induces DELLA degradation through binding with a gibberellin receptor (GID1), and (4) it forms the GID1-(H-acid)-DELLA complex to transduce the gibberellin signal in the same manner as gibberellin. This work shows that the H-acid mode of action acts as an agonist for gibberellin receptor.
1963年，蠕孢醇从真菌稻瘟病菌中分离出来，作为一种天然植物生长调节剂。它表现出类似赤霉素的生物活性，能刺激水稻第二叶鞘的生长。在研究该化合物与一些合成类似物之间的构效关系后，发现蠕孢酸（H-酸）比蠕孢醇具有更高的类似赤霉素活性和化学稳定性。在本研究中，我们表明：（1）H-酸不仅在水稻中，而且在拟南芥中都表现出类似赤霉素的活性；（2）它调节赤霉素相关基因的表达；（3）它通过与赤霉素受体（GID1）结合诱导DELLA降解；（4）它形成GID1-（H-酸）-DELLA复合物，以与赤霉素相同的方式转导赤霉素信号。这项工作表明，H-酸的作用模式作为赤霉素受体的激动剂。
