Identification of Candidate HY5-Dependent and -Independent Regulators of Anthocyanin Biosynthesis in Tomato
Identification of Candidate HY5-Dependent and -Independent Regulators of Anthocyanin Biosynthesis in Tomato
复制标题
番茄花青素生物合成候选 HY5 依赖和独立调节因子的鉴定
DOI：
10.1093/pcp/pcy236
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发表时间：
2019-03-01
影响因子：
4.9
通讯作者：
Cao, Bihao
中科院分区：
文献类型：
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作者：
Qiu, Zhengkun;Wang, Haijing;Cao, Bihao
植物中大量的花青素对生物和非生物逆境具有潜在的保护作用。研究表明，bZIP转录因子HY5在控制花青素积累对光的响应中起着关键作用。然而，在hy5突变体中检测到了残留的花青素，这表明存在其他调控因子以不依赖于HY5的方式调节花青素的生物合成。在这里，我们利用CRISPR/Cas9(簇状规则散布短回文重复序列/CRISPR相关蛋白9)系统，特异性地在紫色番茄品种‘Indigo Rose’中诱导SLHY5的定向突变。由1个碱基插入突变的SLHY5移码零等位基因纯合的番茄植株T2代花青素含量较低。转录分析表明，大多数花青素生物合成结构基因和几个调控基因在hy5突变系中表达下调。通过对hy5突变株系不同组织的转录组分析，确定了8个候选转录因子，它们可能以不依赖于HY5的方式调节花青素的生物合成。这些发现加深了我们对光如何控制花青素积累的理解，并有助于以不依赖于HY5的方式识别花青素生物合成的调控因子。
High quantities of anthocyanins in plants confer potential protective benefits against biotic and abiotic stressors. Studies have shown that the bZIP transcription factor HY5 plays a key role in controlling anthocyanin accumulation in response to light. However, in hy5 mutants, residual anthocyanins have been detected, indicating that other regulators exist to regulate anthocyanin biosynthesis in an HY5-independent manner. Here, we employed the CRISPR/Cas9 (clustered regularly interspersed short palindromic repeats/CRISPR-associated protein 9) system specifically to induce targeted mutagenesis of SlHY5 in the purple tomato cultivar 'Indigo Rose'. The T2 generation of tomato plants homozygous for the null allele of the SlHY5 frameshift mutated by a 1 bp insertion contained a lower anthocyanin content. Transcriptional analysis showed that most of the anthocyanin biosynthesis structural genes and several regulatory genes were down-regulated in the hy5 mutant lines. With transcriptome analyses of the various tissues from hy5 mutant lines, eight candidate transcription factors were identified that may regulate anthocyanin biosynthesis in an HY5-independent manner. These findings deepen our understanding of how light controls anthocyanin accumulation and facilitate the identification of the regulators of anthocyanin biosynthesis in an HY5-independent manner.