まとめ
この研究は,特定のTリンパ腫変異体が,必要なアンカーコンポーネントを追加できないため,TY-1表面抗原をアンカーすることができないことを明らかにしています. この欠陥は,細胞膜での発現の代わりに,Thy-1の分泌につながります.
科学分野:
- 細胞生物学 細胞生物学
- 免疫学 免疫学とは
- バイオケミストリー バイオケミストリー
背景:
- Thy-1は,T細胞機能に不可欠な表面抗原である.
- グリコホスフォリピドアンカーは,多くの表面タンパク質の膜結合を媒介する.
- Thy-1のアンカリングを理解することは,T細胞の信号伝達の鍵です.
研究 の 目的:
- Thy-1表面抗原に対するグリコホスフォリピドアンカリングのメカニズムを解明する.
- 野生型および変異性Tリンパ腫細胞におけるThy-1の生物合成を比較する.
- 変異細胞における表面Thy-1発現の欠如に起因する分子欠陥を特定する.
主な方法:
- D- [2-3H]マノースと [3H]パルミチ酸を用いた生物合成ラベリングの比較研究.
- 野生型および変異性Tリンパ腫細胞 (BW5147およびクラスE) でのThY-1分泌と水性性の分析.
- Thy-1にラベル付きのギャラクトースとフコースの組み込みが評価されました.
主要な成果:
- 変異性Tリンパ腫細胞は,野生型細胞とは異なり,水性であるThy-1を分泌する.
- 変異細胞は,Thy-1に [3H]パルミチン酸を組み込むのに失敗する.
- 両方の細胞タイプは,ラベル付きのギャラクトースとフコースをThy-1に組み込みます.
結論:
- 変異細胞におけるThy-1の表面発現の欠如は,アンカーコンポーネントの追加に失敗したことに起因する.
- グリコホスフォリピドのアンカリングのこの欠陥は,Thy-1. 1の適切な膜局所化を阻害する.
- この研究は,Thy-1.の翻訳後の改変と細胞表面発現における重要なステップを特定しています.
さらに関連する動画
08:02Promoting 3-D Aggregation of FACS Purified Thymic Epithelial Cells with EAK 16-II/EAKIIH6 Self-assembling Hydrogel
Published on: June 27, 2016
09:53Using X-ray Crystallography, Biophysics, and Functional Assays to Determine the Mechanisms Governing T-cell Receptor Recognition of Cancer Antigens
Published on: February 6, 2017
関連する概念動画
Lipids as Anchors
In the plasma membrane, the lipids forming the bilayer can also act as an anchor to tether proteins to the membrane. The three main types of lipid anchors found in eukaryotes are – prenyl groups, fatty acyl groups, and glycosylphosphatidylinositol or GPI groups. Prenyl and fatty acyl groups act as anchors on the cytosolic surface of the membrane, whereas GPI anchors proteins on the extracellular side.
The carboxy-terminal of most of the prenylated proteins, such as Ras proteins, contains the...
The carboxy-terminal of most of the prenylated proteins, such as Ras proteins, contains the...
Tail-anchoring of Proteins in the ER Membrane
Tail-anchored, or TA, proteins are estimated to make up to 3-5% of membrane proteins found in the eukaryotic cell. Such proteins have a single transmembrane domain located approximately 30 amino acid residues upstream from the C-terminal end. As a result, the signal recognition particle (SRP) cannot guide a TA protein to the ER membrane for cotranslational insertion. Hence, they are integrated into the ER membrane post-translationally using their C-terminal end as the anchor. TA proteins...
GPI Anchoring of Proteins in the ER Membrane
GPI-anchoring is a post-translational, reversible protein modification that is ubiquitous in eukaryotes. Such proteins are primarily present on the exoplasmic leaflet of the plasma membrane.
GPI-anchor structure
A sequence of 11 enzymatic reactions results in the synthesis of the complete GPI anchor consisting of a hydrophobic and a hydrophilic portion. The hydrophobic portion comprises phosphatidylinositol, while the hydrophilic part comprises polar groups like phosphoethanolamine,...
GPI-anchor structure
A sequence of 11 enzymatic reactions results in the synthesis of the complete GPI anchor consisting of a hydrophobic and a hydrophilic portion. The hydrophobic portion comprises phosphatidylinositol, while the hydrophilic part comprises polar groups like phosphoethanolamine,...
Receptor Downregulation in MVBs
Multivesicular bodies (MVBs) are mature endosomes that sort ubiquitinated proteins and then fuse with lysosomes to degrade the sorted proteins. Epidermal growth factor (EGF) and its receptor (EGFR) form a complex that can be internalized through endocytosis, sorted into an MVB, and later degraded.
The EGFR can initiate signaling pathways that lead to cell proliferation, migration, and differentiation. Overexpression of EGFR stimulates cells to proliferate. Excessive EGFR activation may...
The EGFR can initiate signaling pathways that lead to cell proliferation, migration, and differentiation. Overexpression of EGFR stimulates cells to proliferate. Excessive EGFR activation may...
Role of Ephrin-Eph Signalling in Intestinal Stem Cell Renewal
Erythropoietin-producing hepatocellular carcinoma receptor (Eph) and its ligand, Eph receptor-interacting protein (Ephrin) were first discovered in the human carcinoma cell line, hence the name. Ephrin-Eph interaction guides cells to reach their appropriate location in adult tissues. They also play an essential role in the immune system by helping in immune cell migration, adhesion, and activation. Based on their structure and function, Eph is divided into two classes — EphA and EphB.
Synthesis and Regulation of Thyroid Hormones
Low blood levels of the thyroid hormones — triiodothyronine (T3) and thyroxine (T4) — signal the hypothalamus to release the thyrotropin-releasing hormone (TRH). TRH then reaches the pituitary gland and stimulates the release of thyroid-stimulating hormone(TSH) into the bloodstream.
Upon reaching the thyroid gland, TSH stimulates the follicular cells' active uptake of iodide ions from the blood. The ions diffuse to the apical surface of the cells and are oxidized to iodine. The iodine is then...
Upon reaching the thyroid gland, TSH stimulates the follicular cells' active uptake of iodide ions from the blood. The ions diffuse to the apical surface of the cells and are oxidized to iodine. The iodine is then...
