Correlation Between GL6 Expression Driven by Varied Promoters and Development of Epidermal Hairs on Leaves of Rice Plant

  Objective  Being one of the important agronomic traits that reflect the yield and physiological functions of a rice plant, the growth and photosynthesis of the fine hairs on the surface of rice leaves were studied.

  Method  The sequences of GL6 gene promoters relating to leaf epidermal hair development were obtained and cloned from different rice varieties. That of Mutant 75-1-127 showing the characteristic epidermal hair development was compared with those of the wild type rice lacking it. The CDS sequence of the mutant gene was cloned. Then, the maize Ubiquitin and cauliflower mosaic virus CaMV35S were used as promoter-driven overexpression vectors to transform the wild-type Japonica rice, Kitaake, mediated by Agrobacterium.

  Result  There were significant differences on the sequences in regions of the genes regulated by the promoters and cloned from different cultivars. The leaves of transgenic rice plants with GL6 driven by maize Ubiquitin promoter had significant hairy phenotype of the typical velvet appearance, but not those involved CaMV35S as a promoter.

  Conclusion  It was clearly demonstrated that the promoters affected the expression of the target gene GL6 and that the epidermal hair development on leaves of Mutant 75-1-127 was derived by the promoter with a unique sequence.