Osaka Prefecture University College of Integrated Arts and Sciences
Osaka Prefecture University College of Integrated Arts and Sciences
Nagoya City University Graduate School of Natural Sciences
Nagoya City University Graduate School of Natural Sciences
Japan Aerospace Exploration Agency Institute of Space and Astronautical Science
出版者
宇宙航空研究開発機構宇宙科学研究本部
出版者（英）
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA/ISAS)
雑誌名
宇宙利用シンポジウム 第20回 平成15年度
雑誌名(英)
Space Utilization Research: Proceedings of the Twentieth Space Utilization Symposium
ページ
102 - 105
発行年
2004-03
抄録（英）
STS-95 space experiments have demonstrated that activities of auxin polar transport in etiolated epicotyls of pea (Pisum sativum L. cv. Alaska) seedlings grown in space were reduced as compared to those under 1 g conditions on the earth, and microgravity conditions induced automorphosis of seedlings (Ueda et al. 1999, 2000), suggesting that gravity substantially controls auxin polar transport as well as growth and development of plants. Strenuous efforts to learn in molecular levels how gravity affects on auxin polar transport in etiolated pea epicotyls resulted in successful separation of PsPIN2 and PsAUX1 genes of putative efflux and influx carrier proteins of auxin, respectively. Phylogenetic analyses based on the deduced amino acid sequences revealed that PsPIN2 belonged to a subcade including AtPIN3, AtPIN4 and AtPIN7, while PsPIN1 (accession no. AY222857, Chawla and DeMason, 2003) belonged to the same subclade as AtPIN1. On the other hand, PsAUX1 showed higher homology with AtAUX1 among AUXs and AUX-like proteins of various plants. Gene expression of PsPIN1 and PsAUX1 in hook region and in the 1st internode of 3.5-d-old etiolated pea seedlings grown under simulated microgravity conditions on a 3-dimensional clinostat was increased as compared with that of the seedlings grown under 1 g conditions, while that of PsPIN2 in the 1st internode was affected little. These results suggest that expression of these genes is under the control of gravity. A possible role of PsPIN2 and PsAUX1 genes for auxin polar transport in etiolated pea seedlings will be discussed.
高等植物におけるオーキシン極性移動関連遺伝子の発現に対する擬似微小重力の影響
