posted on 2023-08-21, 09:43authored byZhaoyong Kang, Yujie Yan, Ruirui Lu, Xiaoqi Dong, Jun Xu, Dong Zheng, Suhua Li, Qingzhi Gao, Shengnan Liu
The artificially synthesized strigolactone (SL) analogue
GR24 is
currently the most widely used reference compound in studying the
biological functions of SLs. To elucidate the structure–activity
relationship and find more promising derivatives with unique molecular
profiles, we design and synthesized three series of novel GR24 derivatives
and explored their activities in hypocotyl and root development of Arabidopsis. Among the 50 synthesized compounds, A11a, A12a, and A20d were found
to have high activities comparable to GR24 for hypocotyl and/or primary
root elongation inhibition in Arabidopsis. Some new analogues have been discovered to exhibit unique activities:
(1) A20c, A21e, and A21o are
specific inhibitors in primary root elongation; (2) A21c, A26c, and A27a exhibit a high promotion
effect on Arabidopsis primary root
elongation; and (3) A27e possesses the most unique profiles
completely opposite to GR24 that promotes both hypocotyl elongation
and primary root development. Moreover, we revealed that the AtD14
receptor does not affect the inhibitory effect of SL analogues in Arabidopsis root development. The ligand–receptor
interactions for the most representative analogues A11a and A27e were deciphered with a long time scale molecular
dynamics simulation study, which provides the molecular basis of their
distinct functions, and may help scientists design novel phytohormones.