Hair, encoding a single C2H2 zinc-finger protein, regulates multicellular trichome formation in tomato
Hair, encoding a single C2H2 zinc-finger protein, regulates multicellular trichome formation in tomato
复制标题
头发编码单个 C2H2 锌指蛋白，调节番茄多细胞毛状体的形成
DOI：
10.1111/tpj.14018
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发表时间：
2018-10-01
期刊：
影响因子：
7.2
通讯作者：
Ye, Zhibiao
中科院分区：
文献类型：
--
作者：
Chang, Jiang;Yu, Ting;Ye, Zhibiao
毛状体起源于几乎所有陆生植物的表皮细胞，是特化的单细胞或多细胞结构。虽然单细胞毛状体形成的分子机制已被广泛研究，但多细胞毛状体形成所必需的大多数基因仍是未知的。在这项研究中，我们通过对180个不同品种番茄i型毛状体的全基因组关联研究（GWAS），确定了10号染色体长臂上的一个相关位点。利用图谱克隆技术，我们克隆了控制这类毛状体起始的关键基因Hair (H)，该基因编码一个C2H2锌指蛋白。转基因实验表明，头发缺失表型是由H的整个编码区缺失引起的。我们鉴定了H的三个等位基因，其中包含几个错义突变和一个核苷酸缺失，分别导致氨基酸替换和阅读框移位。此外，H或Woolly （Wo）的敲低抑制i型毛状体的形成，表明这两种调节因子可能作为异源二聚体起作用。通过pull-down和酵母双杂交实验进一步检测它们之间的直接蛋白相互作用。此外，H在烟草中的异位表达以及H在辣椒和烟草中的同源物在番茄中的异位表达均可触发毛状体的形成。综上所述，这些发现表明H基因可能在茄科物种的多细胞毛状体形成中具有功能保守性。
Trichomes originate from the epidermal cells of nearly all terrestrial plants, which are specialized unicellular or multicellular structures. Although the molecular mechanism regulating unicellular trichome formation has been extensively characterized, most of the genes essential for multicellular trichome formation remain unknown. In this study, we identified an associated locus on the long arm of chromosome 10 using a genome-wide association study (GWAS) on type-I trichomes of 180 diverse Solanum lycopersicum (tomato) accessions. Using map-based cloning we then cloned the key gene controlling the initiation of this type of trichome, named Hair (H), which encodes a single C2H2 zinc-finger protein. Transgenic experiments showed that hair-absent phenotype is caused by the deletion of the entire coding region of H. We identified three alleles of H containing several missense mutations and a nucleotide deletion, which result in amino acid substitutions and a reading frame shift, respectively. In addition, knockdown of H or Woolly (Wo) represses the formation of type-I trichomes, suggesting that both regulators may function as a heterodimer. Direct protein-protein interaction between them was further detected through pull-down and yeast two-hybrid assays. In addition, ectopic expression of H in Nicotiana tabacum (tobacco) and expression of its homologs from Capsicum annuum (pepper) and tobacco in tomato can trigger trichome formation. Taken together, these findings suggest that the H gene may be functionally conserved in multicellular trichome formation in Solanaceae species.