U1 snRNAの変異は,細胞型特異のRNAスプライシングファクターの要件を回避する
K Nandabalan1, L Price, G S Roeder
1Department of Biology, Yale University, New Haven, Connecticut 06511-8112.
Cell
|April 23, 1993
まとめ
MER1タンパク質は,酵母におけるMER2遺伝子のスプライシングに不可欠です. U1 snRNAの突然変異は,MER2イントロン内の塩基配列を変更することで,この要件を回避し,新しいスプライシングメカニズムを強調します.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- RNA スプライシング
背景:
- 酵母MER2遺伝子の効率的なRNAスプライシングは,メイオシス中に発現するMER1タンパク質に依存しています.
- MER2スプライシングにおけるMER1の正確な役割と,このプロセスを制御するメカニズムは,まだ完全に理解されていません.
研究 の 目的:
- MER2 RNAスプライシングにおけるMER1の要件を回避できる遺伝的要因を特定する.
- MER1-独立のMER2スプライシングの基礎となる分子メカニズムを解明する.
主な方法:
- MER1依存を抑制する第二部位変異を隔離するために,遺伝的選択戦略が採用されました.
- サプレッサー変異の配列分析とRNA-DNA相互作用の分析が行われました.
主要な成果:
- U1小核RNA (snRNA) をコードするSNR19の変異は,抑制剤として特定されました.
- この変異により,U1 snRNA配列が変化し,MER2イントロンの5'スペライス部位の外側にある部位とベースペア化することが可能になる.
- MER2 5' スプライスサイトでのコンセンサス配列の復元は,U1 snRNA 塩基ペアリングの増加と相関する,MER1の要件を軽減しました.
結論:
- MER2スプライシングに対するMER1タンパク質の要求は,U1 snRNAの相互作用に影響を与える変異によって回避することができます.
- これは,U1 snRNAが,特定の条件下でスプライシングを容易にするために,イントロン内の非正規のサイトと関わり合える可能性があることを示唆しています.
- この発見は,スプライス部位認識の柔軟性,および酵母菌におけるメオティック遺伝子スプライシングの調節に関する新しい洞察を提供します.
関連する概念動画
RNA Splicing
Splicing is the process by which eukaryotic RNA is edited before its translation into protein. The RNA strand transcribed from eukaryotic DNA is called the primary transcript. The primary transcripts that become mRNAs are called precursor messenger RNAs (pre-mRNAs). Eukaryotic pre-mRNA contains alternating sequences of exons and introns. Exons are nucleotide sequences that code for proteins, whereas introns are the non-coding regions. In RNA splicing, introns are removed and exons are bonded...
RNA Splicing
Splicing is the process by which eukaryotic RNA is edited before its translation into protein. The RNA strand transcribed from eukaryotic DNA is called the primary transcript. The primary transcripts that become mRNAs are called precursor messenger RNAs (pre-mRNAs). Eukaryotic pre-mRNA contains alternating sequences of exons and introns. Exons are nucleotide sequences that code for proteins, whereas introns are the non-coding regions. In RNA splicing, introns are removed and exons are bonded...
Nonsense-mediated mRNA Decay
The Upf proteins that carry out nonsense-mediated decay (NMD) are found in all eukaryotic organisms, including humans. Each protein has an individual role, but they need to work in collaboration. Upf1 is an ATP-dependent RNA helicase that unwinds the RNA helix. Because Upf1 can unwind any RNA, Upf2 and Upf3 are required to help Upf1 discriminate between nonsense and normal mRNAs.
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
Alternative RNA Splicing
Alternative RNA splicing is the regulated splicing of exons and introns to produce different mature mRNAs from a single pre-mRNA. Unlike in constitutive splicing where a single gene produces a single type of mRNA, alternative splicing allows an organism to produce multiple proteins from a single gene and plays an important role in protein diversity.
There are five types of alternative RNA splicing that vary in the ways the pre-mRNA segments are removed or retained in the mature mRNA. The first...
There are five types of alternative RNA splicing that vary in the ways the pre-mRNA segments are removed or retained in the mature mRNA. The first...
Pre-mRNA Processing: RNA Splicing
Splicing is the process by which eukaryotic RNA is edited before its translation into protein. The RNA strand transcribed from eukaryotic DNA is called the primary transcript. The primary transcripts that become mRNAs are called precursor messenger RNAs (pre-mRNAs). Eukaryotic pre-mRNA contains alternating sequences of exons and introns. Exons are nucleotide sequences that code for proteins, whereas introns are the non-coding regions. In RNA splicing, introns are removed and exons are bonded...
Alternative RNA Splicing
Alternative RNA splicing is the regulated splicing of exons and introns to produce different mature mRNAs from a single pre-mRNA. Unlike in constitutive splicing where a single gene produces a single type of mRNA, alternative splicing allows an organism to produce multiple proteins from a single gene and plays an important role in protein diversity.
There are five types of alternative RNA splicing that vary in the ways the pre-mRNA segments are removed or retained in the mature mRNA. The first...
There are five types of alternative RNA splicing that vary in the ways the pre-mRNA segments are removed or retained in the mature mRNA. The first...


