MYB76 Inhibits Seed Fatty Acid Accumulation in Arabidopsis.

Shaowei Duan,Kaige Liu,Mingxun Chen,Changyu Jin,Haoli Ma,Shuanghui Qi,Jiangbo Hai,Chenhao Gao,Dong Li

doi:10.3389/fpls.2017.00226

Abstract

The MYB family of transcription factors is important in regulatory networks controlling development, metabolism and responses to biotic and abiotic stresses in Arabidopsis. However, their role in regulating fatty acid accumulation in seeds is still largely unclear. Here, we found that MYB76, localized in the nucleus, was predominantly expressed in developing seeds during maturation. The myb76 mutation caused a significant increase in the amounts of total fatty acids and several major fatty acid compositions in mature seeds, suggesting that MYB76 functioned as an important repressor during seed oil biosynthesis. RNA sequencing and quantitative real-time PCR analysis revealed remarkable alteration of numerous genes involved in photosynthesis, fatty acid biosynthesis, modification, and degradation, and oil body formation in myb76 seeds at 12 days after pollination. These results help us to understand the novel function of MYB76 and provide new insights into the regulatory network of MYB transcriptional factors controlling seed oil accumulation in Arabidopsis.

Highlights

Fatty acids (FAs) and FA-derived complex lipids stored in the seed serve as the main source of nutrients for humans and livestock, and facilitate successful seed germination and subsequent seedling establishment (Li et al, 2006; Graham, 2008)
This suggested that MYB76 regulates seed oil accumulation mainly occurring at the maturation stage in Arabidopsis seeds (Baud et al, 2002, 2008; Fait et al, 2006; Graham, 2008; Baud and Lepiniec, 2009)
We found that the myb76 mutation resulted in a considerable increase in the amounts of total FAs and several major FA compositions in mature seeds (Figures 2D–F)

Summary

Introduction

Fatty acids (FAs) and FA-derived complex lipids stored in the seed serve as the main source of nutrients for humans and livestock, and facilitate successful seed germination and subsequent seedling establishment (Li et al, 2006; Graham, 2008). They can be wildly used in industries (Lu et al, 2011) and serve as feedstock for biofuels production (Durrett et al, 2008).

Methods

Results

Conclusion