関連する実験動画
Updated: May 26, 2026

11:12
Immunometabolic Circuits in Infection for Advancing Host Directed Therapies
Published on: September 13, 2024
均衡性核酸輸送体3の欠乏は,リソソーム機能とマクロファージのホメオスタシスを乱します
Chia-Lin Hsu1, Weiyu Lin, Dhaya Seshasayee
1Immunology, Genentech Inc., 1 DNA Way, South San Francisco, CA 94080, USA.
まとめ
均衡性ヌクレオシドトランスポーター3 (ENT3) の欠陥は,リゾソームの蓄積と細胞クリアランスの障害を引き起こし,マクロファージ駆動ヒスティオサイトーシスを引き起こす. この研究は,特定のリソソーム貯蔵疾患の背後にある重要なメカニズムを明らかにしています.
科学分野:
- 細胞生物学 細胞生物学
- 遺伝学 遺伝学とは
- 病理生理学 病理生理学とは
背景:
- リソソーム貯蔵疾患 (LSD) は,酵素またはトランスポーターの欠陥の結果であり,細胞の蓄積を引き起こします.
- マクロファージの膨張とヒスティオシトーシスは,いくつかのLSDで起こりますが,その背後にあるメカニズムは不明です.
- 均衡ヌクレオシドトランスポーター3 (ENT3) は,細胞ホメオスタシスに関与するリソソームトランスポーターです.
研究 の 目的:
- マクロファージの機能とヒスティオサイトーシトーシスにおけるENT3の役割を調査する.
- ENT3欠乏症とLSDを結びつける細胞および分子メカニズムを解明する.
- ENT3欠乏マウスにおけるマクロファージの膨張の病理生理学を調査する.
主な方法:
- 均衡性ヌクレオシドトランスポーター3 (ENT3) が欠けているマウスの生成と分析.
- アポプトシス細胞クリアランス,リゾソーム機能,イントラリゾソーム pHの評価.
- マクロファージコロニー刺激因子 (M-CSF) とその受容体 (M-CSFR) の発現とシグナル伝達経路の評価.
主要な成果:
- ENT3欠乏したマウスは,自発的に進行性のマクロファージ主導ヒスティオシトーシスを発症した.
- ENT3の欠乏は,欠陥のあるアポプトシス細胞クリアランス,リゾソームの核酸塩蓄積,および上昇したイントラリゾソームのpHにつながった.
- マクロファージの蓄積は,リゾソームの欠陥による二次的なM-CSFとM-CSFRの信号伝達の増加によって部分的に引き起こされた.
結論:
- ENT3欠乏によって引き起こされるライソソーム欠陥は,アポプトシス細胞のクリアランスを低下させ,ヒスティオサイトーシスを引き起こします.
- 変異したリゾソーム機能と核酸の蓄積は,マクロファージの膨張に重要な貢献者である.
- この研究は,ヒトのENT3関連疾患および他のLSDにおけるヒスティオサイトーシスの細胞および分子基礎を提供します.
関連する概念動画
Lysosomal Hydrolases
Lysosomes are the site for the degradation of macromolecules and biological polymers released during membrane trafficking events such as secretory, endocytic, autophagic, and phagocytic pathways. The membrane-enclosed area of the lysosome, called the lumen, contains hydrolytic enzymes active in an acidic environment. These acid hydrolases are functional at a pH between 4.5 and 5 and are involved in cellular processes such as cell signaling, energy metabolism, restoration of the plasma membrane,...
Biosynthesis of Nucleic Acids
Nucleic acid biosynthesis is a fundamental biochemical process that produces the purine and pyrimidine nucleotides essential for DNA and RNA synthesis. This pathway maintains a balanced nucleotide pool, preventing imbalances that could jeopardize genetic integrity and cellular function. Given the crucial role of nucleotides, their synthesis is tightly regulated to ensure proper cellular homeostasis.Purine BiosynthesisThe biosynthesis of purine nucleotides begins with ribose-5-phosphate, a...
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,...
Pharmacogenetics of Phase II Enzymes: N-acetyltransferase, Thiopurine S-methyltransferase, UDP-glucuronosyltransferase
Phase II biotransformation reactions are essential for detoxifying and eliminating xenobiotics, including many pharmaceutical compounds. These reactions typically involve conjugation, the covalent attachment of polar endogenous groups such as glucuronic acid, sulfate, methyl, or acetyl moieties to functional groups introduced during Phase I metabolism. The resulting conjugates are more water-soluble, enabling efficient renal or biliary excretion.The major classes of Phase II enzymes include...
Pharmacogenetics of Drug Transporters: P-Glycoprotein and Solute Carrier Transporters
The pharmacogenetics of drug transporters is increasingly recognized as a critical factor influencing interindividual variability in drug absorption, distribution, and elimination. These membrane-bound proteins regulate drugs' movement across cellular barriers by actively pumping them out (efflux) or facilitating their uptake (influx). Among the major transporter families, ATP-binding cassette (ABC) and solute carrier (SLC) transporters play particularly prominent roles. Genetic polymorphisms...
pH Regulation in Cells
pH plays a critical role in maintaining normal cellular activities. It helps maintain the structure and function of various proteins, dictates the charge on cellular membranes, and is crucial for metabolic reactions inside the cell. Moreover, cells use the energy from the proton motive force to generate ATP.
Cytosolic pH
Under physiological conditions, the cytosolic pH is slightly more acidic than the extracellular pH. However, cells must prevent further acidification of their cytosol to...
Cytosolic pH
Under physiological conditions, the cytosolic pH is slightly more acidic than the extracellular pH. However, cells must prevent further acidification of their cytosol to...
