pH-dependent domain formation in phosphatidylinositol polyphosphate/phosphatidylcholine mixed vesicles
Phosphatidylinositol polyphosphates (PI-PPs) have been shown to mediate a large variety of physiological processes by attracting proteins to specific cellular sites. Such site-specific signaling requires local accumulation of PI-PPs, and in light of the rich headgroup functionality, it is conceivabl...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
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Elsevier
2005-03-01
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| Series: | Journal of Lipid Research |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S0022227520340359 |
| _version_ | 1818732310013411328 |
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| author | Duane A. Redfern Arne Gericke |
| author_facet | Duane A. Redfern Arne Gericke |
| author_sort | Duane A. Redfern |
| collection | DOAJ |
| description | Phosphatidylinositol polyphosphates (PI-PPs) have been shown to mediate a large variety of physiological processes by attracting proteins to specific cellular sites. Such site-specific signaling requires local accumulation of PI-PPs, and in light of the rich headgroup functionality, it is conceivable that hydrogen bond formation between adjacent headgroups is a contributing factor to the formation of PI-PP-enriched domains. To explore the significance of hydrogen bond formation for the mutual interaction of PI-PPs, this study aims to characterize the pH-dependent phase behavior of phosphatidylcholine/phosphatidylinositol bisphosphate and trisphosphate mixed vesicles by differential scanning calorimetry, infrared transmission spectroscopy, and fluorescence resonance energy transfer measurements. For pH values >7–7.5, the experiments yielded results consistent with dipalmitoylphosphatidylcholine/dipalmitoylphosphatidylinositol polyphosphate gel phase demixing, whereas for moderately acidic conditions, an enhanced mixing was observed. Similarly, this pH-dependent formation of PI-PP-enriched domains was also found for the physiologically important fluid phase.The stability of PI-PP-enriched domains and to some extent the pH dependence of the domain formation was governed by the number as well as the position of the phosphomonoester groups at the inositol ring. |
| first_indexed | 2024-12-17T23:31:32Z |
| format | Article |
| id | doaj.art-c979dac049a24a469658378bb142b8c2 |
| institution | Directory Open Access Journal |
| issn | 0022-2275 |
| language | English |
| last_indexed | 2024-12-17T23:31:32Z |
| publishDate | 2005-03-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of Lipid Research |
| spelling | doaj.art-c979dac049a24a469658378bb142b8c22022-12-21T21:28:40ZengElsevierJournal of Lipid Research0022-22752005-03-01463504515pH-dependent domain formation in phosphatidylinositol polyphosphate/phosphatidylcholine mixed vesiclesDuane A. Redfern0Arne Gericke1Chemistry Department, Kent State University, Kent, OH 44242Chemistry Department, Kent State University, Kent, OH 44242Phosphatidylinositol polyphosphates (PI-PPs) have been shown to mediate a large variety of physiological processes by attracting proteins to specific cellular sites. Such site-specific signaling requires local accumulation of PI-PPs, and in light of the rich headgroup functionality, it is conceivable that hydrogen bond formation between adjacent headgroups is a contributing factor to the formation of PI-PP-enriched domains. To explore the significance of hydrogen bond formation for the mutual interaction of PI-PPs, this study aims to characterize the pH-dependent phase behavior of phosphatidylcholine/phosphatidylinositol bisphosphate and trisphosphate mixed vesicles by differential scanning calorimetry, infrared transmission spectroscopy, and fluorescence resonance energy transfer measurements. For pH values >7–7.5, the experiments yielded results consistent with dipalmitoylphosphatidylcholine/dipalmitoylphosphatidylinositol polyphosphate gel phase demixing, whereas for moderately acidic conditions, an enhanced mixing was observed. Similarly, this pH-dependent formation of PI-PP-enriched domains was also found for the physiologically important fluid phase.The stability of PI-PP-enriched domains and to some extent the pH dependence of the domain formation was governed by the number as well as the position of the phosphomonoester groups at the inositol ring.http://www.sciencedirect.com/science/article/pii/S0022227520340359phosphoinositidelipid demixingcalorimetryinfraredfluorescence |
| spellingShingle | Duane A. Redfern Arne Gericke pH-dependent domain formation in phosphatidylinositol polyphosphate/phosphatidylcholine mixed vesicles Journal of Lipid Research phosphoinositide lipid demixing calorimetry infrared fluorescence |
| title | pH-dependent domain formation in phosphatidylinositol polyphosphate/phosphatidylcholine mixed vesicles |
| title_full | pH-dependent domain formation in phosphatidylinositol polyphosphate/phosphatidylcholine mixed vesicles |
| title_fullStr | pH-dependent domain formation in phosphatidylinositol polyphosphate/phosphatidylcholine mixed vesicles |
| title_full_unstemmed | pH-dependent domain formation in phosphatidylinositol polyphosphate/phosphatidylcholine mixed vesicles |
| title_short | pH-dependent domain formation in phosphatidylinositol polyphosphate/phosphatidylcholine mixed vesicles |
| title_sort | ph dependent domain formation in phosphatidylinositol polyphosphate phosphatidylcholine mixed vesicles |
| topic | phosphoinositide lipid demixing calorimetry infrared fluorescence |
| url | http://www.sciencedirect.com/science/article/pii/S0022227520340359 |
| work_keys_str_mv | AT duanearedfern phdependentdomainformationinphosphatidylinositolpolyphosphatephosphatidylcholinemixedvesicles AT arnegericke phdependentdomainformationinphosphatidylinositolpolyphosphatephosphatidylcholinemixedvesicles |