Scholarlink

<p>Pepper (<i>Capsicum annuum</i> L.) exhibits a significant increase in capsaicinoids accumulation under drought stress, but the transcriptional cascade mechanism regulating this process is still not fully understood. With the increase of drought stress, the contents of capsaicin, dihydrocapsaicin and total capsaicinoids increased significantly. In the severe stress group with soil water, the contents of capsaicin, dihydrocapsaicin and total capsaicinoids increased by 42.87%, 41.29% and 42.48%, respectively. The synthetic structural genes displayed coordinated upregulation, among which capsaicinoids synthesis gene <i>AT3</i> expression increased most markedly with a fold change of 8.80-19.67 times. In this study, a DOF family transcription factor <i>CaCDF3</i> was identified from the transcriptome data of pepper under drought stress, and its expression pattern was significantly positively correlated with the accumulation of capsaicinoids. Subcellular localization analysis showed that <i>CaCDF3</i> was mainly localized in the nucleus. Transient overexpression elevated <i>CaCDF3</i> transcript level to 2.63–5.78 times of control, and <i>AT3</i> expression synchronously increased to 1.66–7.86 times. Correspondingly, the contents of capsaicin, dihydrocapsaicin and total capsaicinoids increased to 1.53–3.69, 0.33–1.84 and 1.44–3.50 times of the control group, respectively. By contrast, VIGS-mediated gene silencing achieved 26.03%–77.08% silencing efficiency of <i>CaCDF3</i>, causing <i>AT3</i> expression to drop by 36.54%–80.71%. The contents of capsaicin, dihydrocapsaicin and total capsaicinoids decreased by 33.24%–65.83%, 27.84%–76.59% and 32.25%–67.79% respectively. Yeast one‑hybrid (Y1H) analysis confirmed that <i>CaCDF3</i> specifically interacts with the <i>AT3</i> promoter region; dual-luciferase reporter assay further verified that <i>CaCDF3</i> enhanced <i>AT3</i> promoter activity by 4.11 times; Electrophoretic mobility shift assay (EMSA) validated the specific binding of CaCDF3 protein with the AAAG motif in the <i>AT3</i> promoter. In summary, this study found that <i>CaCDF3</i> binds to the promoter of the capsaicinoids synthesis gene <i>AT3</i>, thereby regulating its transcription and promoting the accumulation of capsaicinoids, providing new insights into its molecular mechanism.</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

CaCDF3 Positively Regulates Capsaicinoids Biosynthesis Under Drought Stress in Capsicum annuum

  • 期刊论文

  • 发表日期：

    2026年6月26日

查看全文
  • Jiaqin Li,
  • Miao Li,
  • Qing Wen,
  • Yongqing Bai,
  • Xinzhuan Yao,
  • Muhammad Safiullah Virk,
  • Shiyu Tian,
  • Shilai Tian,
  • Hufang Chen,
  • Yumei He,
  • Jianjian Wang,
  • Litang Lu

摘要

Pepper (Capsicum annuum L.) exhibits a significant increase in capsaicinoids accumulation under drought stress, but the transcriptional cascade mechanism regulating this process is still not fully understood. With the increase of drought stress, the contents of capsaicin, dihydrocapsaicin and total capsaicinoids increased significantly. In the severe stress group with soil water, the contents of capsaicin, dihydrocapsaicin and total capsaicinoids increased by 42.87%, 41.29% and 42.48%, respectively. The synthetic structural genes displayed coordinated upregulation, among which capsaicinoids synthesis gene AT3 expression increased most markedly with a fold change of 8.80-19.67 times. In this study, a DOF family transcription factor CaCDF3 was identified from the transcriptome data of pepper under drought stress, and its expression pattern was significantly positively correlated with the accumulation of capsaicinoids. Subcellular localization analysis showed that CaCDF3 was mainly localized in the nucleus. Transient overexpression elevated CaCDF3 transcript level to 2.63–5.78 times of control, and AT3 expression synchronously increased to 1.66–7.86 times. Correspondingly, the contents of capsaicin, dihydrocapsaicin and total capsaicinoids increased to 1.53–3.69, 0.33–1.84 and 1.44–3.50 times of the control group, respectively. By contrast, VIGS-mediated gene silencing achieved 26.03%–77.08% silencing efficiency of CaCDF3, causing AT3 expression to drop by 36.54%–80.71%. The contents of capsaicin, dihydrocapsaicin and total capsaicinoids decreased by 33.24%–65.83%, 27.84%–76.59% and 32.25%–67.79% respectively. Yeast one‑hybrid (Y1H) analysis confirmed that CaCDF3 specifically interacts with the AT3 promoter region; dual-luciferase reporter assay further verified that CaCDF3 enhanced AT3 promoter activity by 4.11 times; Electrophoretic mobility shift assay (EMSA) validated the specific binding of CaCDF3 protein with the AAAG motif in the AT3 promoter. In summary, this study found that CaCDF3 binds to the promoter of the capsaicinoids synthesis gene AT3, thereby regulating its transcription and promoting the accumulation of capsaicinoids, providing new insights into its molecular mechanism.