| Autor: |
Zeng, Zhanghui, Zhang, Wenqian, Shi, Yaqi, Wei, Haonan, Zhou, Chun, Huang, Xiaoping, Chen, Zhehao, Xiang, Taihe, Wang, Lilin, Han, Ning, Bian, Hongwu |
| Zdroj: |
Journal of Agricultural and Food Chemistry; January 2024, Vol. 72 Issue: 2 p1146-1161, 16p |
| Abstrakt: |
Tocotrienols and tocopherols (vitamin E) are potent antioxidants that are synthesized in green plants. Unlike ubiquitous tocopherols, tocotrienols predominantly accumulate in the endosperm of monocot grains, catalyzed by homogentiate geranylgeranyl transferase (HGGT). Previously, we generated a tocotrienol-deficient hvhggtmutant with shrunken barley grains. However, the relationship between tocotrienols and grain development remains unclear. Here, we found that the hvhggtlines displayed hollow endosperms with defective transfer cells and reduced aleurone layers. The carbohydrate and starch contents of the hvhggtendosperm decreased by approximately 20 and 23%, respectively. Weighted gene coexpression network analyses identified a critical gene module containing HvHGGT, which was strongly associated with the hvhggtmutation and enriched with gene functions in starch and sucrose metabolism. Metabolome measurements revealed an elevated soluble sugar content in the hvhggtendosperm, which was significantly associated with the identified gene modules. The hvhggtendosperm had significantly higher NAD(H) and NADP(H) contents and lower levels of ADPGlc (regulated by redox balance) than the wild-type, consistent with the absence of tocotrienols. Interestingly, exogenous α-tocotrienol spraying on developing hvhggtspikes partially rescued starch accumulation and endosperm defects. Our study supports a potential novel function of tocotrienols in grain starch accumulation and endosperm development in monocot crops. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
|
