The Arabidopsis vacuolar sugar transporter SWEET2 limits carbon sequestration from roots and restricts Pythium infection

Hsin Yi Chen, Jung Hyun Huh, Ya Chi Yu, Li Hsuan Ho, Li Qing Chen, Dorothea Tholl, Wolf B. Frommer, Woei Jiun Guo

研究成果: Article同行評審

76 引文 斯高帕斯(Scopus)

摘要

Plant roots secrete a significant portion of their assimilated carbon into the rhizosphere. The putative sugar transporter SWEET2 is highly expressed in Arabidopsis roots. Expression patterns of SWEET2-β-glucuronidase fusions confirmed that SWEET2 accumulates highly in root cells and thus may contribute to sugar secretion, specifically from epidermal cells of the root apex. SWEET2-green fluorescent protein fusions localized to the tonoplast, which engulfs the major sugar storage compartment. Functional analysis of SWEET2 activity in yeast showed low uptake activity for the glucose analog 2-deoxyglucose, consistent with a role in the transport of glucose across the tonoplast. Loss-of-function sweet2 mutants showed reduced tolerance to excess glucose, lower glucose accumulation in leaves, and 15-25% higher glucose-derived carbon efflux from roots, suggesting that SWEET2 has a role in preventing the loss of sugar from root tissue. SWEET2 root expression was induced more than 10-fold during Pythium infection. Importantly, sweet2 mutants were more susceptible to the oomycete, showing impaired growth after infection. We propose that root-expressed vacuolar SWEET2 modulates sugar secretion, possibly by reducing the availability of glucose sequestered in the vacuole, thereby limiting carbon loss to the rhizosphere. Moreover, the reduced availability of sugar in the rhizosphere due to SWEET2 activity contributes to resistance to Pythium.

原文English
頁(從 - 到)1046-1058
頁數13
期刊Plant Journal
83
發行號6
DOIs
出版狀態Published - 2015 九月 1

All Science Journal Classification (ASJC) codes

  • Genetics
  • Plant Science
  • Cell Biology

指紋 深入研究「The Arabidopsis vacuolar sugar transporter SWEET2 limits carbon sequestration from roots and restricts Pythium infection」主題。共同形成了獨特的指紋。

引用此