核融合タンパク質は,哺乳類の細胞と酵母菌の両方の膀媒介による輸送に必須である

D W Wilson¹, C A Wilcox, G C Flynn

¹Department of Biology, Princeton University, New Jersey 08540.

Nature

|June 1, 1989

まとめ

哺乳類の細胞における膀融合に不可欠なタンパク質は,酵母 SEC18 と同等であることが判明しました. この発見は,種と細胞段階を越えて膀輸送のための高度に保存されたメカニズムを明らかにしています.

科学分野:

細胞生物学細胞生物学
分子生物学は分子生物学である.
遺伝学遺伝学とは

背景:

膀輸送は,細胞内の分子,特にエンドプラズマの網膜からゴルジ装置への移動に不可欠です.
タンパク質複合体は,輸送小胞とゴールギ・シスタネのような標的臓器細胞の融合を媒介する.
膀融合の分子機構を理解することは,細胞の組織と機能を解読する鍵です.

研究の目的:

哺乳類の細胞のないシステムで,ゴルギ・システルナエとの膀融合を触媒化するタンパク質を特定し,特徴づけること.
この哺乳類の融合タンパク質が保存され,既知の酵母輸送タンパク質と機能的に関連しているかどうかを判断する.
膀媒介輸送機構の進化的保存を明らかにする.

主な方法:

膀融合におけるN-エチルマレイミド感受性タンパク質活性を研究するために,哺乳類の細胞フリーシステムを利用しました.
中国ハムスターの卵巣細胞から融合タンパク質をコードする遺伝子をクローン化し,配列化しました.
哺乳類のタンパク質の機能と酵母 SEC18 遺伝子産物との比較を目的とした in vitro 試験を実施した.

主要な成果:

N-エチルマレイミドに敏感なタンパク質を特定し,輸送小胞とゴルギの水槽との融合を触媒化する.
この哺乳類の融合タンパク質の遺伝子は,酵母 (Saccharomyces cerevisiae) のSEC18遺伝子製品に相当することを実証しました.
酵母におけるエンドプラズマ網膜からゴルギ装置への膀媒介による輸送におけるSEC18の重要な役割が確認された.

結論:

哺乳類の細胞における膀融合を触媒とするタンパク質は,酵母 SEC18 タンパク質によって機能的に保存されます.
膀融合のメカニズムは,酵母と哺乳類の種間で高度に保存されています.
この保全は,細胞内輸送のさまざまな段階にわたって広がり,基本的な生物学的プロセスを強調しています.

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