2006年1月
Reduction of polar auxin transport in tobacco by the tumorigenic Agrobacterium tumefaciens AK-6b gene
PLANTA
- ,
- ,
- ,
- 巻
- 223
- 号
- 2
- 開始ページ
- 237
- 終了ページ
- 247
- 記述言語
- 英語
- 掲載種別
- 研究論文(学術雑誌)
- DOI
- 10.1007/s00425-005-0080-4
- 出版者・発行元
- SPRINGER
The plant-tumorigenic 6b (AK-6b) gene of Agrobacterium tumefaciens strain AKE10 induces morphological alterations to tobacco plants, Nicotiana tabacum. To investigate the molecular mechanisms underlying these processes, we generated transgenic tobacco harboring the AK-6b gene under the control of a dexamethazone-inducible promoter. Upon induction, transgenic tobacco seedlings exhibited distinct classes of aberrant morphologies, most notably adventitious outgrowths and stunted epicotyls. Histological analysis revealed massive proliferation and altered venation in the newly established outgrowths. Prominent vascular development suggested that auxin metabolism or signaling had been altered. Indeed, basipetal auxin transport in the hypocotyls of the transgenic seedlings was reduced by 50-80%, whereas intracellular auxin contents were only slightly reduced. Analysis of cell extracts by HPLC revealed a large accumulation of phenolic compounds, including the flavonoid kaempferol-3-rutinoside, in transgenic plants compared with wild-type seedlings. As some naturally occurring flavonoids have been shown to affect auxin transport, we suggest that the AK-6b gene expression impairs auxin transport via modulation of phenylpropanoid metabolism, and ultimately results in the observed morphological alterations.
- リンク情報
- ID情報
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- DOI : 10.1007/s00425-005-0080-4
- ISSN : 0032-0935
- Web of Science ID : WOS:000234273500009