Maffucci Tania, Falasca Marco
Inositide Signalling Group, Centre for Diabetes, Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom.
Inositide Signalling Group, Centre for Diabetes, Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom.
Methods Enzymol. 2014;535:75-91. doi: 10.1016/B978-0-12-397925-4.00005-5.
Phosphoinositides (PIs) are minor lipid components of cellular membranes that play critical roles in membrane dynamics, trafficking, and cellular signaling. Among the seven naturally occurring PIs, the monophosphate phosphatidylinositol 3-phosphate (PtdIns3P) and the bisphosphate phosphatidylinositol 3,5-bisphosphate [PtdIns(3,5)P2] have been mainly associated with endosomes and endosomal functions. Metabolic labeling and HPLC analysis revealed that a bulk of PtdIns3P is constitutively present in cells, making it the only detectable product of the enzymes phosphoinositide 3-kinases in unstimulated, normal cells. The use of specific tagged-PtdIns3P-binding domains later demonstrated that this constitutive PtdIns3P accumulates in endosomes where it critically regulates trafficking and membrane dynamics.
磷酸肌醇（PIs）是细胞膜中的微量脂质成分，在膜动力学、运输和细胞信号传导中发挥关键作用。在七种天然存在的PI中，单磷酸磷脂酰肌醇3-磷酸（PtdIns3P）和双磷酸磷脂酰肌醇3,5-二磷酸[PtdIns(3,5)P2]主要与内体及内体功能相关。代谢标记和高效液相色谱分析表明，大量的PtdIns3P在细胞中组成性存在，这使其成为未受刺激的正常细胞中磷酸肌醇3激酶唯一可检测到的产物。后来使用特定的标记PtdIns3P结合结构域证明，这种组成性PtdIns3P在内体中积累，在那里它对运输和膜动力学起着关键调节作用。
