PIP<sub>2</sub> Interacts Electrostatically with MARCKS-like Protein-1 and ENaC in Renal Epithelial Cells
We examined the interaction of a membrane-associated protein, MARCKS-like Protein-1 (MLP-1), and an ion channel, Epithelial Sodium Channel (ENaC), with the anionic lipid, phosphatidylinositol 4, 5-<i>bis</i>phosphate (PIP<sub>2</sub>). We found that PIP<sub>2</sub>...
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MDPI AG
2022-11-01
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| Online Access: | https://www.mdpi.com/2079-7737/11/12/1694 |
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| author | Qiang Yue Otor Al-Khalili Auriel Moseley Masaaki Yoshigi Brandi Michele Wynne Heping Ma Douglas C. Eaton |
| author_facet | Qiang Yue Otor Al-Khalili Auriel Moseley Masaaki Yoshigi Brandi Michele Wynne Heping Ma Douglas C. Eaton |
| author_sort | Qiang Yue |
| collection | DOAJ |
| description | We examined the interaction of a membrane-associated protein, MARCKS-like Protein-1 (MLP-1), and an ion channel, Epithelial Sodium Channel (ENaC), with the anionic lipid, phosphatidylinositol 4, 5-<i>bis</i>phosphate (PIP<sub>2</sub>). We found that PIP<sub>2</sub> strongly activates ENaC in excised, inside-out patches with a half-activating concentration of 21 ± 1.17 µM. We have identified 2 PIP<sub>2</sub> binding sites in the N-terminus of ENaC β and γ with a high concentration of basic residues. Normal channel activity requires MLP-1’s strongly positively charged effector domain to electrostatically sequester most of the membrane PIP<sub>2</sub> and increase the local concentration of PIP<sub>2</sub>. Our previous data showed that ENaC covalently binds MLP-1 so PIP<sub>2</sub> bound to MLP-1 would be near PIP<sub>2</sub> binding sites on the cytosolic N terminal regions of ENaC. We have modified the charge structure of the PIP<sub>2</sub> –binding domains of MLP-1 and ENaC and showed that the changes affect membrane localization and ENaC activity in a way consistent with electrostatic theory. |
| first_indexed | 2024-03-09T17:19:14Z |
| format | Article |
| id | doaj.art-73fd2a2ddafa4118908b9138b8fa2dd4 |
| institution | Directory Open Access Journal |
| issn | 2079-7737 |
| language | English |
| last_indexed | 2024-03-09T17:19:14Z |
| publishDate | 2022-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Biology |
| spelling | doaj.art-73fd2a2ddafa4118908b9138b8fa2dd42023-11-24T13:21:46ZengMDPI AGBiology2079-77372022-11-011112169410.3390/biology11121694PIP<sub>2</sub> Interacts Electrostatically with MARCKS-like Protein-1 and ENaC in Renal Epithelial CellsQiang Yue0Otor Al-Khalili1Auriel Moseley2Masaaki Yoshigi3Brandi Michele Wynne4Heping Ma5Douglas C. Eaton6Division of Nephrology, Department of Medicine, Emory University, Atlanta, GA 30322, USADivision of Nephrology, Department of Medicine, Emory University, Atlanta, GA 30322, USADivision of Nephrology, Department of Medicine, Emory University, Atlanta, GA 30322, USADivision of Nephrology & Hypertension, Department of Internal Medicine, University of Utah, Salt Lake City, UT 84132, USADivision of Nephrology & Hypertension, Department of Internal Medicine, University of Utah, Salt Lake City, UT 84132, USADepartment of Physiology, Emory University, Atlanta, GA 30322, USADivision of Nephrology, Department of Medicine, Emory University, Atlanta, GA 30322, USAWe examined the interaction of a membrane-associated protein, MARCKS-like Protein-1 (MLP-1), and an ion channel, Epithelial Sodium Channel (ENaC), with the anionic lipid, phosphatidylinositol 4, 5-<i>bis</i>phosphate (PIP<sub>2</sub>). We found that PIP<sub>2</sub> strongly activates ENaC in excised, inside-out patches with a half-activating concentration of 21 ± 1.17 µM. We have identified 2 PIP<sub>2</sub> binding sites in the N-terminus of ENaC β and γ with a high concentration of basic residues. Normal channel activity requires MLP-1’s strongly positively charged effector domain to electrostatically sequester most of the membrane PIP<sub>2</sub> and increase the local concentration of PIP<sub>2</sub>. Our previous data showed that ENaC covalently binds MLP-1 so PIP<sub>2</sub> bound to MLP-1 would be near PIP<sub>2</sub> binding sites on the cytosolic N terminal regions of ENaC. We have modified the charge structure of the PIP<sub>2</sub> –binding domains of MLP-1 and ENaC and showed that the changes affect membrane localization and ENaC activity in a way consistent with electrostatic theory.https://www.mdpi.com/2079-7737/11/12/1694MARCKS-like protein-1PIP<sub>2</sub>MARCKS-like-1ENaCmpkCCD cells |
| spellingShingle | Qiang Yue Otor Al-Khalili Auriel Moseley Masaaki Yoshigi Brandi Michele Wynne Heping Ma Douglas C. Eaton PIP<sub>2</sub> Interacts Electrostatically with MARCKS-like Protein-1 and ENaC in Renal Epithelial Cells Biology MARCKS-like protein-1 PIP<sub>2</sub> MARCKS-like-1 ENaC mpkCCD cells |
| title | PIP<sub>2</sub> Interacts Electrostatically with MARCKS-like Protein-1 and ENaC in Renal Epithelial Cells |
| title_full | PIP<sub>2</sub> Interacts Electrostatically with MARCKS-like Protein-1 and ENaC in Renal Epithelial Cells |
| title_fullStr | PIP<sub>2</sub> Interacts Electrostatically with MARCKS-like Protein-1 and ENaC in Renal Epithelial Cells |
| title_full_unstemmed | PIP<sub>2</sub> Interacts Electrostatically with MARCKS-like Protein-1 and ENaC in Renal Epithelial Cells |
| title_short | PIP<sub>2</sub> Interacts Electrostatically with MARCKS-like Protein-1 and ENaC in Renal Epithelial Cells |
| title_sort | pip sub 2 sub interacts electrostatically with marcks like protein 1 and enac in renal epithelial cells |
| topic | MARCKS-like protein-1 PIP<sub>2</sub> MARCKS-like-1 ENaC mpkCCD cells |
| url | https://www.mdpi.com/2079-7737/11/12/1694 |
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