本期《Science》兩項研究提出，涉及硼轉運的基因幫助植物在毒性生長條件下存活,。雖然研究人員還不知道這個微量營養(yǎng)素究竟對植物起什么作用，但是他們知道植物需要適量的硼，太多或太少都對植物的生長不利,。硼毒性在赤道附近國家和旱區(qū)的農業(yè)中最為明顯。現在,，兩項研究對植物如何處理硼提供了一些線索,。在一篇報告中，Tim Sutton和澳大利亞的同事描述了克隆一個大麥的硼轉運基因,、并顯示一種特別能耐高硼的大麥有該基因的多個拷貝,。在另一篇簡報中， Kyoko Miwa和日本的同事揭示,，用基因工程改造后過渡表達一個與硼轉運有關的基因的擬南芥植物,，其生長條件能承受更高的硼。這兩篇文章為基因改造作物使其能耐硼,、從而適應貧瘠土地種植指出了方法,。
原始出處（一）:
Science 30 November 2007:
Vol. 318. no. 5855, pp. 1446 - 1449
DOI: 10.1126/science.1146853
Reports
Boron-Toxicity Tolerance in Barley Arising from Efflux Transporter Amplification
Tim Sutton,* Ute Baumann, Julie Hayes, Nicholas C. Collins, Bu-Jun Shi, Thorsten Schnurbusch, Alison Hay, Gwenda Mayo, Margaret Pallotta, Mark Tester, Peter Langridge
Both limiting and toxic soil concentrations of the essential micronutrient boron represent major limitations to crop production worldwide. We identified Bot1, a BOR1 ortholog, as the gene responsible for the superior boron-toxicity tolerance of the Algerian barley landrace Sahara 3771 (Sahara). Bot1 was located at the tolerance locus by high-resolution mapping. Compared to intolerant genotypes, Sahara contains about four times as many Bot1 gene copies, produces substantially more Bot1 transcript, and encodes a Bot1 protein with a higher capacity to provide tolerance in yeast. Bot1 transcript levels identified in barley tissues are consistent with a role in limiting the net entry of boron into the root and in the disposal of boron from leaves via hydathode guttation.
Australian Centre for Plant Functional Genomics, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Private Mail Bag 1, Glen Osmond, South Australia 5064, Australia.
* To whom correspondence should be addressed. E-mail: [email protected]
