Transcriptome-Wide Identification and Characterization of MYB Transcription Factor Genes in the Laticifer Cells of .

MYB transcription factors hold vital roles in the regulation of plant secondary metabolic pathways. Laticifers in rubber trees (v) are of primary importance in natural rubber production because natural rubber is formed and stored within these structures. To understand the role of MYB transcription factors in the specialized cells, we identified 44 MYB genes (named to ) by using our previously obtained transcriptome database of rubber tree laticifer cells and the public rubber tree genome database. Expression profiles showed that five MYB genes were highly expressed in the laticifers. and were selected for further study. HblMYB19 and HblMYB44 bound the promoters of , , and in yeast. Furthermore, the transient overexpression of HblMYB19 and HblMYB44 in tobacco plants significantly increased the activity of the promoters of , , and . Basing on this information, we proposed that HblMYB19 and HblMYB44 are the regulators of , , and , which are involved in the biosynthesis pathway of natural rubber.