RTD1 INVOLVED IN TOCOPHEROL BIOSYNTHESIS AND PLANT DEVELOPMENT IN RICE
Tocopherols are one of the most important antioxidants with roles in living organisms. The functions of tocopherols have been characterized in animals and artificial membranes. However, the genetic and molecular functions of tocopherols in plants are less understood. The team of Yunhui Zhang from Jiangsu Academy of Agricultural Sciences aims to study a tocopherol-deficient mutant rice, rtd1.
The rtd1 mutant showed overall growth retardation throughout its growth period. Most of the agronomic traits were also impaired in rtd1. Analysis revealed that the RTD1 gene encoded homogentisate phytyltransferase, an enzyme catalyzing a key step in tocopherol biosynthesis. RTD1 was also found to be expressed in green leafy tissues, and the protein was located in chloroplasts. Cold tolerance was also found to be reduced in the rtd1 mutant.
The rtd1 mutant also exhibited a reduced response to gibberellin (GA). However, the GA content was not changed, suggesting a transcriptional regulation of SLR1.
These findings implied that tocopherols play important roles in regulating rice growth and development.