Scholarlink

Key message <p>The transcription factor LbaR2R3-MYB3 of goji promotes the biosynthesis of wax components including alkanes, alcohols, fatty acids, and ketones, increases total leaf cuticular wax load, and consequently enhances tobacco resistance to powdery mildew.</p> Abstract <p>Goji (<i>Lycium barbarum</i>) is one of the important economic forest species in northwest China. Powdery mildew is a common disease of goji plants that significantly reduces yield and quality, causing substantial economic losses for growers. Cuticular wax serves as the first physical barrier protecting plants against both biotic and abiotic stresses. Members of the R2R3-MYB transcription factor family in goji have not been previously reported, and the relationship between the key member LbaR2R3-MYB3 and cuticular wax biosynthesis and powdery mildew resistance remains unclear. Therefore, this study employed “Ningqi I” goji as the experimental material and identified 75 R2R3-MYB transcription factor family members distributed across 11 chromosomes in the genome. The goji LbaR2R3-MYB proteins mainly localized in the nucleus, mitochondria, cytoplasm, and chloroplasts. Ten conserved motifs were identified in LbaR2R3-MYB3 proteins, with Motif1, Motif2, and Motif3 being the most widely distributed. The promoters of these family members contain multiple cis-acting elements responsive to hormones and abiotic stress. Members of the LbaR2R3-MYB transcription factor family exhibited evolutionary instability. The <i>LbaR2R3-MYB3</i> gene was cloned from goji leaves yielding a 756&#xa0;bp fragment. Heterologous expression vectors were successfully constructed, and transgenic tobacco lines overexpressing LbaR2R3-MYB3 (LbaR2R3-MYB3-OE) were obtained. Compared with wild-type tobacco, the cuticular wax load in transgenic tobacco leaves was significantly increased by 1.82-fold, with significant increases in alkanes, alcohols, fatty acids, and ketones. The transgenic tobacco lines showed a 38.2% reduction in powdery mildew incidence and a 59.8% decrease in disease index compared to WT, indicating significantly enhanced resistance to powdery mildew. These results demonstrate that the transcription factor LbaR2R3-MYB3 promotes the biosynthesis of wax components including alkanes, alcohols, fatty acids, and ketones, increases total leaf cuticular wax load, and consequently enhances tobacco resistance to powdery mildew.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Identification of the R2R3-MYB transcription factor family in goji and LbaR2R3-MYB3 mediated wax biosynthesis enhancing powdery mildew resistance in tobacco

  • 期刊论文

  • 发表日期：

    2026年6月30日

查看全文
  • Xingbin Wang,
  • Jie Li,
  • Sitian Li,
  • Xiao Zhang,
  • Jing Wang,
  • Tong Hou,
  • Jing He

摘要

Key message

The transcription factor LbaR2R3-MYB3 of goji promotes the biosynthesis of wax components including alkanes, alcohols, fatty acids, and ketones, increases total leaf cuticular wax load, and consequently enhances tobacco resistance to powdery mildew.

Abstract

Goji (Lycium barbarum) is one of the important economic forest species in northwest China. Powdery mildew is a common disease of goji plants that significantly reduces yield and quality, causing substantial economic losses for growers. Cuticular wax serves as the first physical barrier protecting plants against both biotic and abiotic stresses. Members of the R2R3-MYB transcription factor family in goji have not been previously reported, and the relationship between the key member LbaR2R3-MYB3 and cuticular wax biosynthesis and powdery mildew resistance remains unclear. Therefore, this study employed “Ningqi I” goji as the experimental material and identified 75 R2R3-MYB transcription factor family members distributed across 11 chromosomes in the genome. The goji LbaR2R3-MYB proteins mainly localized in the nucleus, mitochondria, cytoplasm, and chloroplasts. Ten conserved motifs were identified in LbaR2R3-MYB3 proteins, with Motif1, Motif2, and Motif3 being the most widely distributed. The promoters of these family members contain multiple cis-acting elements responsive to hormones and abiotic stress. Members of the LbaR2R3-MYB transcription factor family exhibited evolutionary instability. The LbaR2R3-MYB3 gene was cloned from goji leaves yielding a 756 bp fragment. Heterologous expression vectors were successfully constructed, and transgenic tobacco lines overexpressing LbaR2R3-MYB3 (LbaR2R3-MYB3-OE) were obtained. Compared with wild-type tobacco, the cuticular wax load in transgenic tobacco leaves was significantly increased by 1.82-fold, with significant increases in alkanes, alcohols, fatty acids, and ketones. The transgenic tobacco lines showed a 38.2% reduction in powdery mildew incidence and a 59.8% decrease in disease index compared to WT, indicating significantly enhanced resistance to powdery mildew. These results demonstrate that the transcription factor LbaR2R3-MYB3 promotes the biosynthesis of wax components including alkanes, alcohols, fatty acids, and ketones, increases total leaf cuticular wax load, and consequently enhances tobacco resistance to powdery mildew.