リボソームレベルは,ヒトの血液形成における翻訳と血統結合を選択的に調節する
Rajiv K Khajuria1, Mathias Munschauer2, Jacob C Ulirsch3
1Division of Hematology/Oncology, Boston Children's Hospital and Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Berlin-Brandenburg School for Regenerative Therapies, Charité-Universitätsmedizin Berlin, Berlin 13353, Germany.
Cell
|March 20, 2018
まとめ
ダイヤモンド - ブラックファン 貧血 (DBA) は,リボソーム 濃度 の 低下 で は なく,血球 の 形成 を 損なう こと を 示し て い ます. この発見は,血液形成幹細胞および前身細胞 (HSPC) の正常および破壊された赤血球系統のコミットメントの重要なレギュレータとしてリボソームレベルを強調しています.
科学分野:
- 血液学
- 分子生物学
- 遺伝学
背景:
- 血球形成は伝統的に階層的な分化モデルに従う.
- 最近の研究では,血液形成性幹細胞と祖先細胞 (HSPC) の早期の系統結合が示唆されている.
- これらの洗練されたモデルの規制と疾患の関連性はよく理解されていません.
研究 の 目的:
- 正常状態と病気状態における系統的コミットメントプログラミングのメカニズム的基礎を調査する.
- ダイヤモンド・ブラックファン貧血 (DBA) でのリボソームタンパク質変異の役割と,赤色素系に与える影響を調査する.
- リボソームのレベルの変化が 細胞の分化にどう影響するかを理解する
主な方法:
- 遺伝的な血液疾患であるダイアモンド・ブラックファン貧血 (DBA) の患者を研究した.
- 血液形成幹細胞と原始細胞 (HSPC) のリボソームレベルと組成を分析した.
- 変異したリボソームレベルがトランスクリプトの翻訳と系統のコミットメントに与える影響を調査した.
主要な成果:
- DBAは,利用可能なリボソームのプールが限られ,リボソーム組成が一定であることが特徴です.
- リボソームのレベルが全体的に低下すると,特定のトランスクリプトの翻訳に不釣り合いが起こります.
- 選択されたトランスクリプトの翻訳がHSPCに減少したことが,赤色線維系統の結合を阻害することが示された.
結論:
- リボソームのレベルは 構成ではなく 細胞の分化において 重要な規制的な役割を果たします
- DBAにおける赤血球系統のコミットメントの障害は,リボソームの利用可能性が限られているため,特定のトランスクリプトの翻訳の減少と関連しています.
- この研究は,血液細胞の形成と病気の病原性の新しい規制メカニズムを明らかにしています.
関連する概念動画
Lineage Commitment
4.4K
Commitment is the process whereby stem cells:
4.4K
Ribosomes
77.4K
Ribosomes translate genetic information encoded by messenger RNA (mRNA) into proteins. Both prokaryotic and eukaryotic cells have ribosomes. Cells that synthesize large quantities of protein—such as secretory cells in the human pancreas—can contain millions of ribosomes.
Ribosome Structure and Assembly
Ribosomes are composed of ribosomal RNA (rRNA) and proteins. In eukaryotes, rRNA is transcribed from genes in the nucleolus—a part of the nucleus that specializes in ribosome...
Ribosome Structure and Assembly
Ribosomes are composed of ribosomal RNA (rRNA) and proteins. In eukaryotes, rRNA is transcribed from genes in the nucleolus—a part of the nucleus that specializes in ribosome...
77.4K
Translational Regulation
677
Translational regulation in prokaryotes ensures efficient protein synthesis by controlling ribosome access to mRNA. This regulation is mediated by secondary RNA structures, including translational riboswitches, RNA thermometers, and small RNAs (sRNAs), which respond to intracellular and environmental signals to modulate gene expression.Translational RiboswitchesRiboswitches in the leader region of mRNAs can regulate translation by altering the accessibility of the Shine-Dalgarno (SD) sequence,...
677
Translation
157.3K
Lesson: Translation
Translation is the process of synthesizing proteins from the genetic information carried by messenger RNA (mRNA). Following transcription, it constitutes the final step in the expression of genes. This process is carried out by ribosomes, complexes of protein and specialized RNA molecules. Ribosomes, transfer RNA (tRNA), and other proteins produce a chain of amino acids—the polypeptide—as the end product of translation.
Translation Produces the Building Blocks of...
Translation is the process of synthesizing proteins from the genetic information carried by messenger RNA (mRNA). Following transcription, it constitutes the final step in the expression of genes. This process is carried out by ribosomes, complexes of protein and specialized RNA molecules. Ribosomes, transfer RNA (tRNA), and other proteins produce a chain of amino acids—the polypeptide—as the end product of translation.
Translation Produces the Building Blocks of...
157.3K
Initiation of Translation
39.2K
Initiating translation is complex because it involves multiple molecules. Initiator tRNA, ribosomal subunits, and eukaryotic initiation factors (eIFs) are all required to assemble on the initiation codon of mRNA. This process consists of several steps that are mediated by different eIFs.
First, the initiator tRNA must be selected from the pool of elongator tRNAs by eukaryotic initiation factor 2 (eIF2). The initiator tRNA (Met-tRNAi) has conserved sequence elements including modified bases at...
First, the initiator tRNA must be selected from the pool of elongator tRNAs by eukaryotic initiation factor 2 (eIF2). The initiator tRNA (Met-tRNAi) has conserved sequence elements including modified bases at...
39.2K
Termination of Translation
27.9K
The large ribosomal subunit has several important structures essential to translation. These include the peptidyl transferase center (PTC) - which is the site where the peptide bond is formed - and a large, internal, water-filled tube through which the nascent polypeptide moves. This latter structure is called the Peptide Exit Tunnel, and it begins at the PTC and spans the body of the large ribosomal subunit. During translation, as the nascent polypeptide chain is synthesized, it passes through...
27.9K


