Open AccessThe rice Os NAC 6 transcription factor orchestrates multiple molecular mechanisms involving root structural adaptions and nicotianamine biosynthesis for drought tolerance
Author(s) -
Lee DongKeun,
Chung Pil Joong,
Jeong Jin Seo,
Jang Geupil,
Bang Seung Woon,
Jung Harin,
Kim Youn Shic,
Ha SunHwa,
Choi Yang Do,
Kim JuKon
Publication year - 2017
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.12673
Subject(s) - biology , drought tolerance , rhizosphere , transgene , genetically modified crops , reprogramming , transcription factor , gene , microbiology and biotechnology , mutant , botany , biochemistry , genetics , bacteria
Summary Drought has a serious impact on agriculture worldwide. A plant's ability to adapt to rhizosphere drought stress requires reprogramming of root growth and development. Although physiological studies have documented the root adaption for tolerance to the drought stress, underlying molecular mechanisms is still incomplete, which is essential for crop engineering. Here, we identified Os NAC 6 ‐mediated root structural adaptations, including increased root number and root diameter, which enhanced drought tolerance. Multiyear drought field tests demonstrated that the grain yield of Os NAC 6 root‐specific overexpressing transgenic rice lines was less affected by drought stress than were nontransgenic controls. Genome‐wide analyses of loss‐ and gain‐of‐function mutants revealed that Os NAC 6 up‐regulates the expression of direct target genes involved in membrane modification, nicotianamine ( NA ) biosynthesis, glutathione relocation, 3′‐phophoadenosine 5′‐phosphosulphate accumulation and glycosylation, which represent multiple drought tolerance pathways. Moreover, overexpression of NICOTIANAMINE SYNTHASE genes, direct targets of Os NAC 6, promoted the accumulation of the metal chelator NA and, consequently, drought tolerance. Collectively, Os NAC 6 orchestrates novel molecular drought tolerance mechanisms and has potential for the biotechnological development of high‐yielding crops under water‐limiting conditions.