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Dual role of SND1 facilitates efficient communication between abiotic stress signalling and normal growth in Arabidopsis.

ABSTRACT: Certain plant cells synthesize secondary cell walls besides primary cell walls. This biosynthesis is strictly controlled by an array of transcription factors. Here, we show that SND1, a regulator of cell-wall biosynthesis, regulates abscisic acid (ABA) biosynthesis to ensure optimal plant growth. In Arabidopsis, the lack of SND1 and its homolog NST1 leads to the deficiency of secondary cell walls, preventing snd1nst1 double mutant seedlings from growing upright. Compared to wild type seedlings, the snd1 knockout mutant seedlings accumulated less anthocyanin and exhibited low tolerance to salt stress. Compared to wild type seedlings, the snd1 knockout seedlings were more sensitive to salt stress. Although SND1 can bind to the promoter of Myb46, we observed that SND1 binds directly to the promoter of the ABI4 gene, thereby reducing ABA levels under normal growth conditions. Thus, plants adjust secondary cell wall thickening and growth via SND1. SND1 has a dual function: it activates the Myb46 pathway, fostering lignin biosynthesis to produce sufficient cell wall components for growth, while maintaining a low ABA concentration, as it inhibits growth. This dual function of SND1 may help plants modulate their growth efficiently.

SUBMITTER: Jeong CY

PROVIDER: S-EPMC6031621 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Dual role of SND1 facilitates efficient communication between abiotic stress signalling and normal growth in Arabidopsis.

Jeong Chan Young CY Lee Won Je WJ Truong Hai An HA Trịnh Cao Sơn CS Jin Joo Yeon JY Kim Sulhee S Hwang Kwang Yeon KY Kang Chon-Sik CS Moon Joon-Kwan JK Hong Suk-Whan SW Lee Hojoung H

Scientific reports 20180704 1

Certain plant cells synthesize secondary cell walls besides primary cell walls. This biosynthesis is strictly controlled by an array of transcription factors. Here, we show that SND1, a regulator of cell-wall biosynthesis, regulates abscisic acid (ABA) biosynthesis to ensure optimal plant growth. In Arabidopsis, the lack of SND1 and its homolog NST1 leads to the deficiency of secondary cell walls, preventing snd1nst1 double mutant seedlings from growing upright. Compared to wild type seedlings, ...[more]

PMID: 29973639

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Dataset Information

Dual role of SND1 facilitates efficient communication between abiotic stress signalling and normal growth in Arabidopsis.

Publications

Dual role of SND1 facilitates efficient communication between abiotic stress signalling and normal growth in Arabidopsis.

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