Hair, encoding a single C2H2 zinc‐finger protein, regulates multicellular trichome formation in tomato. (30th July 2018)

• Record Type: Journal Article
• Authors: Chang, Jiang; Yu, Ting; Yang, Qihong; Li, Changxing; Xiong, Cheng; Gao, Shenghua; Xie, Qingmin; Zheng, Fangyan; Li, Hanxia; Tian, Zhendong; Yang, Changxian; Ye, Zhibiao
• Is Part Of: Plant journal. Volume 96:Number 1(2018)
• Page Start: 90
• Page End: 102
• Publication Date: 2018-07-30
• Subjects: hair absent -- tomato -- trichomes -- Woolly -- zinc‐finger protein; Plant molecular biology -- Periodicals; Plant cells and tissues -- Periodicals; Botany -- Periodicals; 580
• DOI: 10.1111/tpj.14018
• Languages: English
• ISSNs: 0960-7412

Abstract

Summary: 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. Significance Statement: In this study, we cloned and identified the H gene, responsible for multicellular trichome formation, through GWAS and map‐based cloning. H regulates the initiation of type‐I trichomes by interacting with Wo, which may be functionally conserved in multicellular trichome formation in Solanaceae species. This result will provide a basis to elucidate the regulatory pathway of multicellular trichome formation and cell fate determination in plants.