2010年
The role of the rice aquaporin Lsi1 in arsenite efflux from roots
NEW PHYTOLOGIST
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- 巻
- 186
- 号
- 2
- 開始ページ
- 392
- 終了ページ
- 399
- 記述言語
- 英語
- 掲載種別
- 研究論文(学術雑誌)
- DOI
- 10.1111/j.1469-8137.2010.03192.x
- 出版者・発行元
- WILEY-BLACKWELL PUBLISHING, INC
When supplied with arsenate (As(V)), plant roots extrude a substantial amount of arsenite (As(III)) to the external medium through as yet unidentified pathways. The rice (Oryza sativa) silicon transporter Lsi1 (OsNIP2;1, an aquaporin channel) is the major entry route of arsenite into rice roots. Whether Lsi1 also mediates arsenite efflux was investigated.
Expression of Lsi1 in Xenopus laevis oocytes enhanced arsenite efflux, indicating that Lsi1 facilitates arsenite transport bidirectionally.
Arsenite was the predominant arsenic species in arsenate-exposed rice plants. During 24-h exposure to 5 mu M arsenate, rice roots extruded arsenite to the external medium rapidly, accounting for 60-90% of the arsenate uptake. A rice mutant defective in Lsi1 (lsi1) extruded significantly less arsenite than the wild-type rice and, as a result, accumulated more arsenite in the roots. By contrast, Lsi2 mutation had little effect on arsenite efflux to the external medium.
We conclude that Lsi1 plays a role in arsenite efflux in rice roots exposed to arsenate. However, this pathway accounts for only 15-20% of the total efflux, suggesting the existence of other efflux transporters.
Expression of Lsi1 in Xenopus laevis oocytes enhanced arsenite efflux, indicating that Lsi1 facilitates arsenite transport bidirectionally.
Arsenite was the predominant arsenic species in arsenate-exposed rice plants. During 24-h exposure to 5 mu M arsenate, rice roots extruded arsenite to the external medium rapidly, accounting for 60-90% of the arsenate uptake. A rice mutant defective in Lsi1 (lsi1) extruded significantly less arsenite than the wild-type rice and, as a result, accumulated more arsenite in the roots. By contrast, Lsi2 mutation had little effect on arsenite efflux to the external medium.
We conclude that Lsi1 plays a role in arsenite efflux in rice roots exposed to arsenate. However, this pathway accounts for only 15-20% of the total efflux, suggesting the existence of other efflux transporters.
- リンク情報
- ID情報
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- DOI : 10.1111/j.1469-8137.2010.03192.x
- ISSN : 0028-646X
- ORCIDのPut Code : 9166172
- Web of Science ID : WOS:000276024900020