マイクロRNA-22323による原始細胞増殖と粒細胞機能の調節
Jonathan B Johnnidis1, Marian H Harris, Robert T Wheeler
1Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142, USA.
Nature
|February 19, 2008
まとめ
マイクロRNA-223 (miR-223) は,粒細胞の産生と炎症反応を微調整する. マウスにおけるmiR-223の喪失は,膨張した粒細胞,炎症の増加,組織損傷を引き起こす.
科学分野:
- 分子生物学は分子生物学である.
- 免疫学 免疫学とは
- 遺伝学 遺伝学とは
背景:
- マイクロRNA (miRNA) は,哺乳類においてほとんど未知の機能を持つ遺伝子発現の重要な調節体である.
- ミエロイドに特異的なマイクロRNA-223 (miR-223) は,ミエロイドの発達に関与しているが,その正確な役割は不明である.
研究 の 目的:
- ミエロイド原始細胞の発達と粒細胞生物学におけるmiR-223の機能を調査する.
- miR-223が粒子の形成と炎症を調節する分子メカニズムを解明する.
主な方法:
- ミウスの機能喪失アレルを利用して,miR-223の役割を研究した.
- その影響を評価するために,miR-223の標的であるMef2cの遺伝的アブレーションを使用した.
- 野生型およびmiR-223変異マウスの粒細胞の分化,活性化,および炎症反応を分析した.
主要な成果:
- miR-223欠乏症は,原始細胞の増殖による膨張した粒細胞区間をもたらした.
- Mef2cはmiR-223の直接標的として特定され,Mef2cの除去により,原始細胞の膨張が救われました.
- miR-223が欠けていた粒細胞は,過度な成熟度,活性化に対する過敏度,および強化された真菌駆除活性を示した.
- miR-223変異マウスは,自発的な肺病変と,エンドトキシンに挑戦した際の過剰な組織損傷を発症した.
結論:
- miR-223は,粒状細胞の祖先の増殖と微分化の重要な負の調節剤として作用します.
- miR-223は粒細胞の活性化を微調整し,炎症反応を制御し,過度の組織損傷を防ぐ.
さらに関連する動画
関連する概念動画
Differentiation of Common Myeloid Progenitor Cells
Common myeloid progenitors (CMPs) are oligopotent cells that can differentiate into granulocytes and macrophages. Granulocytes and macrophages are essential for protecting the body against bacterial, viral, or fungal infections. They migrate from the bone marrow into the circulating blood to reach specific tissue sites where they differentiate and help in immune surveillance. However, they survive only for a few days and must be continuously made available to the organism to maintain a robust...
Regulation of Hematopoietic Stem Cells
All blood and immune cells are produced from the multipotent hematopoietic stem cells (HSCs) by the process of hematopoiesis. However, they all have a limited life span. In addition, many are depleted in immune surveillance or combatting an injury or infection. This makes blood one of the most regenerative tissues. Hematopoiesis helps replenish these blood and immune cells, restoring the body's normal functioning. However, overproduction of blood and immune cells can make them cancerous or...
MicroRNAs
MicroRNA (miRNA) are short, regulatory RNA transcribed from introns (non-coding regions of a gene) or intergenic regions (stretches of DNA present between genes). Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself, forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA...
MicroRNAs
MicroRNA (miRNA) are short, regulatory RNA transcribed from introns—non-coding regions of a gene—or intergenic regions—stretches of DNA present between genes. Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA ends...
Role Of Notch Signalling In Intestinal Stem Cell Renewal
Notch signaling was first discovered in Drosophila melanogaster, where it is involved in cell lineage differentiation. Notch signaling regulates the maintenance and differentiation of intestinal stem cells or ISCs by controlling the expression of atonal homolog 1 or Atoh1. Atoh1 directs cells to differentiate into secretory cells.
Direct cell-to-cell contact is needed for the activation of Notch signaling. The signal is initiated when a notch ligand binds to a receptor on an adjacent cell, also...
Direct cell-to-cell contact is needed for the activation of Notch signaling. The signal is initiated when a notch ligand binds to a receptor on an adjacent cell, also...
Abnormal Proliferation
Under normal conditions, most adult cells remain in a non-proliferative state unless stimulated by internal or external factors to replace lost cells. Abnormal cell proliferation is a condition in which the cell's growth exceeds and is uncoordinated with normal cells. In such situations, cell division persists in the same excessive manner even after cessation of the stimuli, leading to persistent tumors. The tumor arises from the damaged cells that replicate to pass the damage to the daughter...


