<p>In this study, we investigated the genetic control of dwarfism in naturally occurring dwarf mutant lines of grapevines. Through trait–segregation and marker–trait association analyses, we identified a major locus on Chromosome 14 tightly associated with the dwarf trait. Subsequently, we conducted a bulked RNA-seq analysis, fine mapped the dwarf trait and identified <i>VviBR6OX1</i>, a cytochrome P450 enzyme involved in brassinosteroid synthesis, as a candidate gene for the observed dwarfism. RNA-seq sequence analyses revealed two in-frame deletions in the gene: a 12-bp deletion in exon 1 and a 9-bp deletion in exon 4. A survey of the two indels in <i>Vitis</i> germplasm suggested that the 9-bp deletion is most likely the cause of dwarfism in the mutant. We recreated similar dwarf grapevines by knocking out <i>VviBR6OX1</i> using CRISPR/Cas9 gene editing and confirmed <i>VviBR6OX1</i>’s role in controlling vine architecture. Additionally, we observed several vines with an extreme compact dwarf phenotype and determined that the compact dwarfing phenotype was a result of simultaneous editing of a second <i>BR6OX</i> gene, <i>VviBR6OX2</i>. The discovery of BR-related dwarfism in grapevine provides an important genetic avenue for developing desirable vine architecture for various breeding purposes.</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

First brassinosteroid-based dwarf mutant discovered and characterized in grapevine

  • Yingzhen Yang,
  • Jie Arro,
  • Cheng Zou,
  • Madeline Oravec,
  • Bruce Reisch,
  • Gan-Yuan Zhong

摘要

In this study, we investigated the genetic control of dwarfism in naturally occurring dwarf mutant lines of grapevines. Through trait–segregation and marker–trait association analyses, we identified a major locus on Chromosome 14 tightly associated with the dwarf trait. Subsequently, we conducted a bulked RNA-seq analysis, fine mapped the dwarf trait and identified VviBR6OX1, a cytochrome P450 enzyme involved in brassinosteroid synthesis, as a candidate gene for the observed dwarfism. RNA-seq sequence analyses revealed two in-frame deletions in the gene: a 12-bp deletion in exon 1 and a 9-bp deletion in exon 4. A survey of the two indels in Vitis germplasm suggested that the 9-bp deletion is most likely the cause of dwarfism in the mutant. We recreated similar dwarf grapevines by knocking out VviBR6OX1 using CRISPR/Cas9 gene editing and confirmed VviBR6OX1’s role in controlling vine architecture. Additionally, we observed several vines with an extreme compact dwarf phenotype and determined that the compact dwarfing phenotype was a result of simultaneous editing of a second BR6OX gene, VviBR6OX2. The discovery of BR-related dwarfism in grapevine provides an important genetic avenue for developing desirable vine architecture for various breeding purposes.