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PbrMYB21, a novel MYB protein of Pyrus betulaefolia, functions in drought tolerance and modulates polyamine levels by regulating arginine decarboxylase gene.

ABSTRACT: MYB comprises a large family of transcription factors that play significant roles in plant development and stress response in plants. However, knowledge concerning the functions of MYBs and the target genes remains poorly understood. Here, we report the identification and functional characterization of a novel stress-responsive MYB gene from Pyrus betulaefolia. The MYB gene, designated as PbrMYB21, belongs to the R2R3-type and shares high degree of sequence similarity to MdMYB21. The transcript levels of PbrMYB21 were up-regulated under various abiotic stresses, particularly dehydration. PbrMYB21 was localized in the nucleus with transactivation activity. Overexpression of PbrMYB21 in tobacco conferred enhanced tolerance to dehydration and drought stresses, whereas down-regulation of PbrMYB21 in Pyrus betulaefolia by virus-induced gene silencing (VIGS) resulted in elevated drought sensitivity. Transgenic tobacco exhibited higher expression levels of ADC (arginine decarboxylase) and accumulated larger amount of polyamine in comparison with wild type (WT). VIGS of PbrMYB21 in Pyrus betulaefolia down-regulated ADC abundance and decreased polyamine level, accompanied by compromised drought tolerance. The promoter region of PbrADC contains one MYB-recognizing cis-element, which was shown to be interacted with PbrMYB21, indicating the ADC may be a target gene of PbrMYB21. Take together, these results demonstrated that PbrMYB21 plays a positive role in drought tolerance, which may be, at least in part, due to the modulation of polyamine synthesis by regulating the ADC expression.

SUBMITTER: Li K

PROVIDER: S-EPMC5552480 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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PbrMYB21, a novel MYB protein of Pyrus betulaefolia, functions in drought tolerance and modulates polyamine levels by regulating arginine decarboxylase gene.

Li Kongqing K Xing Caihua C Yao Zhenghong Z Huang Xiaosan X

Plant biotechnology journal 20170401 9

MYB comprises a large family of transcription factors that play significant roles in plant development and stress response in plants. However, knowledge concerning the functions of MYBs and the target genes remains poorly understood. Here, we report the identification and functional characterization of a novel stress-responsive MYB gene from Pyrus betulaefolia. The MYB gene, designated as PbrMYB21, belongs to the R2R3-type and shares high degree of sequence similarity to MdMYB21. The transcript ...[more]

PMID: 28190292

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Dataset Information

PbrMYB21, a novel MYB protein of Pyrus betulaefolia, functions in drought tolerance and modulates polyamine levels by regulating arginine decarboxylase gene.

Publications

PbrMYB21, a novel MYB protein of Pyrus betulaefolia, functions in drought tolerance and modulates polyamine levels by regulating arginine decarboxylase gene.

Similar Datasets

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