植物の乾燥:リボヌクレアースによるものではないポリソームの喪失

R S Dhindsa, J D Bewley

Science (New York, N.Y.)

|January 16, 1976

まとめ

干ばつに耐えるモスは,リボヌクレアース活性が増加する前に,乾燥中にポリソームを失います. この損失は,RNAの分解ではなく,リボソーム流出と再形成が失敗した初期複合体によるものです.

科学分野:

植物生理学植物生理学
分子生物学は分子生物学である.
干ばつ耐性メカニズム

背景:

ポリソームはタンパク質合成に不可欠です.
植物における乾燥ストレスは,重要な生理学的変化につながる可能性があります.
Tortula ruralisは,植物の乾燥耐性を研究するためのモデル生物です.

研究の目的:

乾燥中のTortula ruralisのポリソーム喪失の背後にあるメカニズムを調査する.
ポリソームの分解におけるリボヌクレアース活動の役割を決定する.
ストレス下でのポリソーム維持におけるリボソーム機能の関与を解明する.

主な方法:

乾燥および水分化されたTortula ruralis.のポリソームレベルを定量化する.
乾燥中のリボヌクレアース活性測定.
リボソーム-メッセンジャーRNA複合性の分析.

主要な成果:

ポリソームのレベルは,リボヌクレアース活性が観察される前に,乾燥中に著しく減少します.
乾燥したモスのリボソームは,メッセンジャーRNAの断片と複合していないことが判明しました.
証拠は,メッセンジャーRNAの再始動の欠如を示唆しています.

結論:

乾燥中のポリソーム損失は,リボソーム流出によって媒介されます.
開始複合体の再形成が失敗すると,ポリソームの損失に寄与する.
これらのメカニズムは,Tortula ruralisの極端な脱水時に翻訳機構を保護します.

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