70Sリボソーム機能複合体のX線結晶構造
J H Cate1, M M Yusupov, G Z Yusupova
1Center for Molecular Biology of RNA, Sinsheimer Laboratories, University of California, Santa Cruz, CA 95064, USA. cate@wi.mit.edu
まとめ
X線結晶学では,メッセンジャーRNA (mRNA) と転送RNA (tRNA) を含む70Sリボソーム複合体の詳細な構造が明らかになる. これらの構造は,tRNAとリボソームRNA (rRNA) 構成要素の間の重要な相互作用を明らかにし,タンパク質合成を理解するのに役立ちます.
科学分野:
- 構造生物学 構造生物学とは
- 分子生物学は分子生物学である.
- バイオケミストリー バイオケミストリー
背景:
- 70Sリボソームは,タンパク質合成を担う分子機構である.
- リボソームの構造を理解することは,翻訳機構の解読の鍵です.
研究 の 目的:
- リボソーム-tRNA-mRNA相互作用の高解像度構造的基礎を解明する.
- 70Sリボソーム内のtRNA結合と位置づけを制御する分子接触を視覚化します.
主な方法:
- 70Sリボソーム複合体の構造を決定するために,X線結晶学を用いた.
- 高解像度データ (最大7.8アングストーム) は,分子細部を視覚化することを可能にしました.
主要な成果:
- メッセンジャーRNA (mRNA) と転送RNA (tRNA) を含む70Sリボソーム複合体の詳細な構造が得られた.
- 30SサブユニットとP-tRNAアンチコドン幹ループの間の特定の相互作用が特定されました.
- A-tRNAのアンチコドン領域がより露出していることが観察されました.
- スイッチヘリックスと解読部位を含む,サブユニットインターフェイスで16SリボソームRNA (rRNA) を含む相互作用のネットワークが明らかにされました.
結論:
- 解明された構造は,トランスレーション中のtRNA結合と位置づけに関する前例のない洞察を提供します.
- この発見は,リボソーム内の機能的相互作用を媒介する特定のrRNA要素の役割を強調しています.
- これらの結果は,タンパク質合成の基礎となる分子機構のより深い理解に貢献します.
関連する概念動画
X-ray Crystallography
The size of the unit cell and the arrangement of atoms in a crystal may be determined from measurements of the diffraction of X-rays by the crystal, termed X-ray crystallography.
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
Protein and Protein Structure
Proteins are one of the most abundant organic molecules in living systems and have the most diverse range of functions of all macromolecules. Proteins may be structural, regulatory, contractile, or protective. They may serve in transport, storage, or membranes; or they may be toxins or enzymes. Their structures, like their functions, vary greatly. They are all, however, amino acid polymers arranged in a linear sequence.
A protein's shape is critical to its function. For example, an enzyme can...
A protein's shape is critical to its function. For example, an enzyme can...
Globular and Fibrous Proteins
Many proteins can be classified into two distinct subtypes - globular or fibrous. These two types differ in their shapes and solubilities.
Globular proteins are also known as spheroproteins and typically are approximately round in shape. They contain a mix of amino acid types and contain differing sequences in their primary structures. Globular proteins have many different functions, such as enzymes, cellular messengers, and molecular transporters. These roles often require the proteins to be...
Globular proteins are also known as spheroproteins and typically are approximately round in shape. They contain a mix of amino acid types and contain differing sequences in their primary structures. Globular proteins have many different functions, such as enzymes, cellular messengers, and molecular transporters. These roles often require the proteins to be...
X-ray Diffraction of Biological Samples
X-ray diffraction or XRD is an analytical tool that utilizes X-rays to study ordered structures such as crystalline organic and inorganic samples, polycrystalline materials, proteins, carbohydrates, and drugs.
According to Bragg's law, when X-rays strike the sample positioned on a stage, the rays are scattered by the electron clouds around the sample atoms. The X-ray diffraction or scattering is caused by constructive interference of the X-ray waves that reflect off the internal crystal...
According to Bragg's law, when X-rays strike the sample positioned on a stage, the rays are scattered by the electron clouds around the sample atoms. The X-ray diffraction or scattering is caused by constructive interference of the X-ray waves that reflect off the internal crystal...
Nucleic Acid Structure
The pentose sugar in DNA is deoxyribose, while in RNA the pentose sugar is ribose. The difference between the sugars is the presence of the hydroxyl group on the ribose's second carbon and a hydrogen on the deoxyribose's second carbon. The phosphate residue attaches to the hydroxyl group of the 5′ carbon of one sugar and the hydroxyl group of the 3′ carbon of the sugar of the next nucleotide, which forms a 5′ to 3′ phosphodiester linkage.
DNA Structure
DNA has a double-helix structure. The...
DNA Structure
DNA has a double-helix structure. The...
Transducer Mechanism: Nuclear Receptors
Nuclear receptors, or NRs, are unique transcription factors that regulate gene transcription and affect the cellular pathways involved in reproduction, development, or metabolism. Their ability to be stimulated by small lipophilic ligands and control vital cellular processes makes them ideal drug targets. Nearly 10-15% of currently prescribed drugs target these receptors.
About 48 different soluble family members of nuclear receptors are identified that can be divided into two main classes:
About 48 different soluble family members of nuclear receptors are identified that can be divided into two main classes:


