Open AccessThe auxin receptor TIR 1 homolog (Pag FBL 1) regulates adventitious rooting through interactions with Aux/ IAA 28 in Populus
Author(s) -
Shu Wenbo,
Zhou Houjun,
Jiang Cheng,
Zhao Shutang,
Wang Liuqiang,
Li Quanzi,
Yang Zhangqi,
Groover Andrew,
Lu MengZhu
Publication year - 2019
Publication title -
plant biotechnology journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.525
H-Index - 115
eISSN - 1467-7652
pISSN - 1467-7644
DOI - 10.1111/pbi.12980
Subject(s) - auxin , biology , primordium , arabidopsis , microbiology and biotechnology , lateral root , transcriptome , cambium , botany , cutting , gene expression , gene , xylem , biochemistry , mutant
Summary Adventitious roots occur naturally in many species and can also be induced from explants of some tree species including Populus , providing an important means of clonal propagation. Auxin has been identified as playing a crucial role in adventitious root formation, but the associated molecular regulatory mechanisms need to be elucidated. In this study, we examined the role of Pag FBL 1 , the hybrid poplar ( Populus alba × P . glandulosa clone 84K) homolog of Arabidopsis auxin receptor TIR 1, in adventitious root formation in poplar. Similar to the distribution pattern of auxin during initiation of adventitious roots, Pag FBL 1 expression was concentrated in the cambium and secondary phloem in stems during adventitious root induction and initiation phases, but decreased in emerging adventitious root primordia. Overexpressing Pag FBL 1 stimulated adventitious root formation and increased root biomass, while knock‐down of Pag FBL 1 transcript levels delayed adventitious root formation and decreased root biomass. Transcriptome analyses of Pag FBL 1 overexpressing lines indicated that an extensive remodelling of gene expression was stimulated by auxin signalling pathway during early adventitious root formation. In addition, Pag IAA 28 was identified as downstream targets of Pag FBL 1. We propose that the Pag FBL 1 ‐ Pag IAA 28 module promotes adventitious rooting and could be targeted to improve Populus propagation by cuttings.