Osmotic stress represses strigolactone biosynthesis in Lotus japonicus roots: exploring the interaction between strigolactones and ABA under abiotic stress
Type
ArticleAuthors
Liu, JunweiHe, Hanzi
Vitali, Marco
Visentin, Ivan
Charnikhova, Tatsiana V.
Haider, Imran

Schubert, Andrea
Ruyter-Spira, Carolien P.
Bouwmeester, Harro J J
Lovisolo, Claudio
Cardinale, Francesca
KAUST Department
Biological and Environmental Science and Engineering (BESE) DivisionCenter for Desert Agriculture
Date
2015-02-26Online Publication Date
2015-02-26Print Publication Date
2015-06Permanent link to this record
http://hdl.handle.net/10754/566142
Metadata
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Main conclusion: Strigolactone changes and cross talk with ABA unveil a picture of root-specific hormonal dynamics under stress.Abstract: Strigolactones (SLs) are carotenoid-derived hormones influencing diverse aspects of development and communication with (micro)organisms, and proposed as mediators of environmental stimuli in resource allocation processes; to contribute to adaptive adjustments, therefore, their pathway must be responsive to environmental cues. To investigate the relationship between SLs and abiotic stress in Lotus japonicus, we compared wild-type and SL-depleted plants, and studied SL metabolism in roots stressed osmotically and/or phosphate starved. SL-depleted plants showed increased stomatal conductance, both under normal and stress conditions, and impaired resistance to drought associated with slower stomatal closure in response to abscisic acid (ABA). This confirms that SLs contribute to drought resistance in species other than Arabidopsis. However, we also observed that osmotic stress rapidly and strongly decreased SL concentration in tissues and exudates of wild-type Lotus roots, by acting on the transcription of biosynthetic and transporter-encoding genes and independently of phosphate abundance. Pre-treatment with exogenous SLs inhibited the osmotic stress-induced ABA increase in wild-type roots and down-regulated the transcription of the ABA biosynthetic gene LjNCED2. We propose that a transcriptionally regulated, early SL decrease under osmotic stress is needed (but not sufficient) to allow the physiological increase of ABA in roots. This work shows that SL metabolism and effects on ABA are seemingly opposite in roots and shoots under stress.Citation
Liu, J., He, H., Vitali, M., Visentin, I., Charnikhova, T., Haider, I., … Cardinale, F. (2015). Osmotic stress represses strigolactone biosynthesis in Lotus japonicus roots: exploring the interaction between strigolactones and ABA under abiotic stress. Planta, 241(6), 1435–1451. doi:10.1007/s00425-015-2266-8Publisher
Springer NatureJournal
Plantaae974a485f413a2113503eed53cd6c53
10.1007/s00425-015-2266-8