哺乳动物细胞膜中溶解脂酶D活性的表征
Yuhuan Xie1, Krishna M Ella1, Terra C Gibbs1
1Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, SC 29425, USA.
Cells
|March 27, 2024
概括
这项研究确定了在各种哺乳动物细胞中膜局部化的lysophospholipase D (lyso-PLD) 活性,该活性会产生lysophosphatidic acid (LPA). 这种与膜相关的lys-PLD活性与分泌形式不同,有助于细胞LPA的产生.
科学领域:
- 生物化学 生物化学
- 细胞生物学 细胞生物学
- 脂质代谢 脂质代谢是什么
背景情况:
- Lysophosphatidic 酸 (LPA) 是一种关键的脂质媒介,通过 G 蛋白结合受体参与各种细胞功能.
- 由光酶A2 (PLA2) 生产的光脂可以通过光酸酶D (lyso-PLD) 转化为LPA.
- 虽然分泌的lysos-PLDs的特征很好,但膜局部化的lysos-PLDs仍然不太了解.
研究的目的:
- 为了研究在哺乳动物细胞系中与膜相关的溶解脂酶D (lyso-PLD) 活性的存在和特征.
- 确定这种膜溶解-PLD活性是否有助于产生溶解酸 (LPA).
- 区分膜lys-PLD活动与其他脂酶D (PLD) 活动以及已知分泌的lys-PLD.
主要方法:
- 在体外酶试验中使用光基质测量LPA生成.
- 从多种哺乳动物细胞系 (PC12,A7r5,老鼠-1,PC-3,SKOV-3,OVCAR-3) 的膜片中分析LPA的产生.
- 使用瓦纳酸盐和酸盐的酶抑制研究,PLD2过度表达的评估和siRNA敲击实验.
主要成果:
- 来自测试细胞系的膜分离物表现出lysol-PLD活性,从光基-lysophosphatidylcholine和天然lysophospholipids产生LPA.
- 膜lyso-PLD活性与PLD活性区别于差异性抑制剂敏感性和对PLD2过度表达缺乏反应.
- 包括siRNA敲除在内的证据表明,膜lysos-PLD与分泌的酶自毒素不同.
- 发现PC-3细胞表达了膜局部化的lysol-PLDs GDE4和GDE7.
结论:
- 哺乳动物细胞膜具有明显的lyso-PLD活性,能够产生LPA.
- 这种与膜相关的lyso-PLD有助于LPA的细胞池.
- 这些发现突出了通过膜结合酶介导的LPA生成的新途径.
相关概念视频
Asymmetric Lipid Bilayer
7.2K
Biological membranes show uneven distribution of different types of lipids in the inner and outer layers, resulting in transverse asymmetric membranes. The treatment of the erythrocyte membrane with the enzyme phospholipase confirmed the asymmetric nature of the lipid bilayer. The enzyme hydrolyzes lipids into fatty acids and hydrophilic groups. The phospholipase acts only on the outer layer of the membrane, while the inner layer remains intact. The phospholipase treatment resulted in 80%...
7.2K
Membrane Lipids
23.9K
Lipids are an essential component of all biological membranes. The average lipid content in mammalian membranes is 50%, though it can be as low as 20% in the inner mitochondrial membrane or as high as 80% in the myelin sheath present around the nerve cells.
Phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, and sphingomyelin are the most common phospholipids present in mammalian membranes. At physiological pH, phosphatidylserine is negatively charged, while the other three...
Phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, and sphingomyelin are the most common phospholipids present in mammalian membranes. At physiological pH, phosphatidylserine is negatively charged, while the other three...
23.9K
Detergent Purification of Membrane Proteins
5.2K
Detergents are used to purify the integral proteins of the membrane. The hydrophobic portion of the detergent can replace membrane phospholipids while solubilizing the membrane proteins. When detergent monomers reach a specific concentration in a solution called critical micelle concentration (CMC), they form micelles. Above CMC, the concentration of the detergent monomers remains in equilibrium with the micelle. The number of detergent monomers present in the CMC varies for each detergent, and...
5.2K
Lysosomes
17.8K
Lysosomes are membrane-enclosed spherical sacs derived from the Golgi apparatus. The most important function of the lysosome is degrading macromolecules and biological polymers that are released during membrane trafficking events such as the secretory, endocytic, autophagic, and phagocytic pathways. The degradation is carried out by several hydrolytic enzymes active in an acidic environment of the lysosomal lumen. These acid hydrolases are involved in cellular processes such as cell signaling,...
17.8K
Synthesis of Phosphatidylcholine in the ER Membrane
3.1K
The ER synthesizes lipids for building cell membranes and performing cellular functions such as energy storage and signaling. The lipid synthesis machinery embedded in the ER membrane primarily collects all reactants from the cytosol. Following synthesis, the secretory pathway and the ER contact sites distribute these lipids to other cellular organelles. Additionally, the energy-rich triacylglycerides are transported from the ER via lipid droplets.
The major components of all eukaryotic cell...
The major components of all eukaryotic cell...
3.1K
Lipid Digestion
91.6K
Lipids are large molecules that are generally not water-soluble. Since most of the digestive enzymes in the human body are water-based, there are specific steps the body must take to break down lipids and make them available for use.
91.6K


