タンパク質チロシンフォスファタゼに関連するRNA5'-トリフォスファタゼ
1Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA.
Cell
|June 13, 1997
まとめ
研究者は,C. elegansのキャピング酵素 (CEL-1) を特定し,そのN端RNAトリホスファタゼドメインがタンパク質チロシンホスファタゼ (PTP) と類似性を共有し,PTP型の酵素スーパーファミリーを拡大することを明らかにしました.
科学分野:
- 分子生物学は分子生物学である.
- 酵素学 酵素学とは
- 遺伝学 遺伝学とは
背景:
- mRNAキャピングは,RNAトリフォスファタゼ,グアニルトランスファーゼ,メチルトランスファーゼ活動を含む遺伝子発現に不可欠です.
- C. elegansのキャピング酵素 (CEL-1) は,その酵素的機能について調査されています.
研究 の 目的:
- 遺伝子CEL-1とその暗号化されたタンパク質を特徴付けるために.
- C. elegansキャピング酵素の酵素活性と構造領域を解明する.
主な方法:
- CEL-1の遺伝子特性について
- CEL-1ドメインのシーケンス分析.
- 酵素測定法により,RNAトリフォスファタゼとタンパク質チロシンフォスファタゼの活性を決定する.
主要な成果:
- CEL-1は,酵母およびワクチンウイルス酵素と同質のC端のグアニリルトランスファーゼドメインを有しています.
- CEL-1のN端領域はRNAトリフォスファタゼ活性を示しています.
- このRNAトリホスファタゼドメインは,タンパク質チロシンホスファタゼ (PTP) との配列類似性を示しているが,PTPの活性性は欠けている.
- RNAトリフォスファタゼのメカニズムは,PTPに似た,保存された核性システインを含みます.
結論:
- CEL-1は,C. elegansのキャピング酵素であり,異なるN端RNAトリフォスファタゼとC端ガンイリルトランスファーゼドメインを有する.
- CEL-1のRNAトリフォスファタゼ活動は,既知のPTP型フォスファタゼのスーパーファミリーを,RNA基板に作用する酵素を含むように拡張します.
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