Journal
PLANT SCIENCE
Volume 313, Issue -, Pages -Publisher
ELSEVIER IRELAND LTD
DOI: 10.1016/j.plantsci.2021.111089
Keywords
Phloem unloading; Sugar metabolism; Carboxyfluorescein imaging; Sugar transporter; Xanthoceras sorbifolia
Categories
Funding
- Fundamental Research Funds for the Central Universities [2015ZCQ-LX-02]
Ask authors/readers for more resources
The research revealed the sugar transport mechanisms in Xanthoceras sorbifolia fruit and identified XsSWEET10 protein as a key player in this process.
The process of phloem unloading and post-unloading transport of photoassimilate is critical to crop output. Xanthoceras sorbifolia is a woody oil species with great biomass energy prospects in China; however, under -production of seeds seriously restricts its development. Here, our cytological studies by ultrastructural obser-vation revealed that the sieve element-companion cell complex in carpellary bundle was symplasmically interconnected with surrounding parenchyma cells at the early and late fruit developmental stages, whereas it was symplasmically isolated at middle stage. Consistently, real-time imaging showed that fluorescent tracer 6(5) carboxyfluorescein was confined to phloem strands at middle stage but released into surrounding parenchymal cells at early and late stages. Enzymatic assay showed that sucrose synthase act as the key enzyme catalyzing the progress of Suc degradation post-unloading pathway whether in pericarp or in seed, while vacuolar acid invertase and neutral invertase play compensation roles in sucrose decomposition. Sugar transporter XsSWEET10 had a high expression profile in fruit, especially at middle stage. XsSWEET10 is a plasma membrane-localized protein and heterologous expression in SUC2-deficient yeast strain SUSY7/ura3 confirmed its ability to uptake sucrose. These findings approved the transition from symplasmic to apoplasmic phloem unloading in Xanthoceras sorbifolia fruit and XsSWEET10 as a key candidate in sugar transport.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available