Objective   Regulation functions of JsMYB108 and JsMYB305 on the promoters of three terpene synthase genes (TPSs) relating to the aroma synthesis of jasmine were analyzed.

  Method   The promoter fragments of JsTPSs were cloned by genome walking with the DNA of jasmine leaves as template to determine the sequences of the cis-acting elements in them. The fragments were constructed separately in the reporter vector pGWB433. Then, tobacco leaves were transformed with the reporter vector alone or with pK7FWG2.0-JsMYB108 and pK7FWG2.0-JsMYB305 effect vectors to detect the activation of JsMYB108 and JsMYB305 on the promoters. Binding of JsMYB108 and JsMYB305 to the promoters was verified by the yeast one-hybrid assay.

  Result   The cloned promoter fragments of the three JsTPSs were 1 357 bp, 1 849 bp, and 1 005 bp with MYB recognition sites. The elements relating to light response, damage response, and abscisic acid induced cis-acting were predicted in different promoter sequences. The GUS staining and activity detection in tobacco leaves confirmed varying degrees of activity of the fragments by introducing JsMYB108 and JsMYB305. Comparing to control, JsMYB108 expanded the activities 1.96-fold on the promoter of JsTPS1, 6.47-fold on that of JsTPS3, and 4.15-fold on that of JsTPS4, while JsMYB305 did 1.57-fold, 15.18-fold, and 3.12-fold, respectively. The yeast one-hybrid assay further verified the bindings of JsMYB108 and JsMYB305 to JsTPS1, JsTPS3, and JsTPS4.

  Conclusion   JsMYB108 and JsMYB305 could activate the promoters of JsTPS1, JsTPS3, andJsTPS4. These two transcription factors might play a key role in the synthesis and metabolism of aromatic terpenes in jasmine flowers.