SCP-2/SCP-x gene ablation alters lipid raft domains in primary cultured mouse hepatocytess⃞
Although reverse cholesterol transport from peripheral cell types is mediated through plasma membrane microdomains termed lipid rafts, almost nothing is known regarding the existence, protein/lipid composition, or structure of these putative domains in liver hepatocytes, cells responsible for the ne...
| Main Authors: | , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Elsevier
2007-10-01
|
| Series: | Journal of Lipid Research |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S0022227520424642 |
| _version_ | 1828942656949977088 |
|---|---|
| author | Barbara P. Atshaves Avery L. McIntosh H. Ross Payne Adalberto M. Gallegos Kerstin Landrock Nobuyo Maeda Ann B. Kier Friedhelm Schroeder |
| author_facet | Barbara P. Atshaves Avery L. McIntosh H. Ross Payne Adalberto M. Gallegos Kerstin Landrock Nobuyo Maeda Ann B. Kier Friedhelm Schroeder |
| author_sort | Barbara P. Atshaves |
| collection | DOAJ |
| description | Although reverse cholesterol transport from peripheral cell types is mediated through plasma membrane microdomains termed lipid rafts, almost nothing is known regarding the existence, protein/lipid composition, or structure of these putative domains in liver hepatocytes, cells responsible for the net removal of cholesterol from the body. Lipid rafts purified from hepatocyte plasma membranes by a nondetergent affinity chromatography method were: i) present at 33 ± 3% of total plasma membrane protein; ii) enriched in key proteins of the reverse cholesterol pathway [scavenger receptor class B type I (SR-B1), ABCA1, P-glycoprotein (P-gp), sterol carrier protein-2 (SCP-2)]; iii) devoid of caveolin-1; iv) enriched in cholesterol, sphingomyelin, GM1, and phospholipids low in polyunsaturated fatty acid and double bond index; and v) exhibited an intermediate liquid-ordered lipid phase with significant transbilayer fluidity gradient. Ablation of the gene encoding SCP-2 significantly altered lipid rafts to: i) increase the proportion of lipid rafts present, thereby increasing raft total content of ABCA1, P-gp, and SR-B1; ii) increase total phospholipids while decreasing GM1 in lipid rafts; iii) decrease the fluidity of lipid rafts, consistent with the increased intermediate liquid-ordered phase; and iv) abolish the lipid raft transbilayer fluidity gradient. Thus, despite the absence of caveolin-1 in liver hepatocytes, lipid rafts represented nearly one-third of the mouse hepatocyte plasma membrane proteins and displayed unique protein, lipid, and biophysical properties that were differentially regulated by SCP-2 expression. |
| first_indexed | 2024-12-14T03:59:53Z |
| format | Article |
| id | doaj.art-2415db37d61c42f8a8f338cc9fa9019b |
| institution | Directory Open Access Journal |
| issn | 0022-2275 |
| language | English |
| last_indexed | 2024-12-14T03:59:53Z |
| publishDate | 2007-10-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of Lipid Research |
| spelling | doaj.art-2415db37d61c42f8a8f338cc9fa9019b2022-12-21T23:18:00ZengElsevierJournal of Lipid Research0022-22752007-10-01481021932211SCP-2/SCP-x gene ablation alters lipid raft domains in primary cultured mouse hepatocytess⃞Barbara P. Atshaves0Avery L. McIntosh1H. Ross Payne2Adalberto M. Gallegos3Kerstin Landrock4Nobuyo Maeda5Ann B. Kier6Friedhelm Schroeder7Department of Physiology and Pharmacology, Texas A&M University, Texas Veterinary Medical Center, College Station, TX 77843-4466Department of Physiology and Pharmacology, Texas A&M University, Texas Veterinary Medical Center, College Station, TX 77843-4466Department of Pathobiology, Texas A&M University, TVMC, College Station, TX 77843-4467Department of Pathobiology, Texas A&M University, TVMC, College Station, TX 77843-4467Department of Physiology and Pharmacology, Texas A&M University, Texas Veterinary Medical Center, College Station, TX 77843-4466Department of Pathology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7525Department of Pathobiology, Texas A&M University, TVMC, College Station, TX 77843-4467Department of Physiology and Pharmacology, Texas A&M University, Texas Veterinary Medical Center, College Station, TX 77843-4466Although reverse cholesterol transport from peripheral cell types is mediated through plasma membrane microdomains termed lipid rafts, almost nothing is known regarding the existence, protein/lipid composition, or structure of these putative domains in liver hepatocytes, cells responsible for the net removal of cholesterol from the body. Lipid rafts purified from hepatocyte plasma membranes by a nondetergent affinity chromatography method were: i) present at 33 ± 3% of total plasma membrane protein; ii) enriched in key proteins of the reverse cholesterol pathway [scavenger receptor class B type I (SR-B1), ABCA1, P-glycoprotein (P-gp), sterol carrier protein-2 (SCP-2)]; iii) devoid of caveolin-1; iv) enriched in cholesterol, sphingomyelin, GM1, and phospholipids low in polyunsaturated fatty acid and double bond index; and v) exhibited an intermediate liquid-ordered lipid phase with significant transbilayer fluidity gradient. Ablation of the gene encoding SCP-2 significantly altered lipid rafts to: i) increase the proportion of lipid rafts present, thereby increasing raft total content of ABCA1, P-gp, and SR-B1; ii) increase total phospholipids while decreasing GM1 in lipid rafts; iii) decrease the fluidity of lipid rafts, consistent with the increased intermediate liquid-ordered phase; and iv) abolish the lipid raft transbilayer fluidity gradient. Thus, despite the absence of caveolin-1 in liver hepatocytes, lipid rafts represented nearly one-third of the mouse hepatocyte plasma membrane proteins and displayed unique protein, lipid, and biophysical properties that were differentially regulated by SCP-2 expression.http://www.sciencedirect.com/science/article/pii/S0022227520424642sterol carrier proteinSR-B1reverse cholesterol transportABCA1 |
| spellingShingle | Barbara P. Atshaves Avery L. McIntosh H. Ross Payne Adalberto M. Gallegos Kerstin Landrock Nobuyo Maeda Ann B. Kier Friedhelm Schroeder SCP-2/SCP-x gene ablation alters lipid raft domains in primary cultured mouse hepatocytess⃞ Journal of Lipid Research sterol carrier protein SR-B1 reverse cholesterol transport ABCA1 |
| title | SCP-2/SCP-x gene ablation alters lipid raft domains in primary cultured mouse hepatocytess⃞ |
| title_full | SCP-2/SCP-x gene ablation alters lipid raft domains in primary cultured mouse hepatocytess⃞ |
| title_fullStr | SCP-2/SCP-x gene ablation alters lipid raft domains in primary cultured mouse hepatocytess⃞ |
| title_full_unstemmed | SCP-2/SCP-x gene ablation alters lipid raft domains in primary cultured mouse hepatocytess⃞ |
| title_short | SCP-2/SCP-x gene ablation alters lipid raft domains in primary cultured mouse hepatocytess⃞ |
| title_sort | scp 2 scp x gene ablation alters lipid raft domains in primary cultured mouse hepatocytess⃞ |
| topic | sterol carrier protein SR-B1 reverse cholesterol transport ABCA1 |
| url | http://www.sciencedirect.com/science/article/pii/S0022227520424642 |
| work_keys_str_mv | AT barbarapatshaves scp2scpxgeneablationalterslipidraftdomainsinprimaryculturedmousehepatocytess AT averylmcintosh scp2scpxgeneablationalterslipidraftdomainsinprimaryculturedmousehepatocytess AT hrosspayne scp2scpxgeneablationalterslipidraftdomainsinprimaryculturedmousehepatocytess AT adalbertomgallegos scp2scpxgeneablationalterslipidraftdomainsinprimaryculturedmousehepatocytess AT kerstinlandrock scp2scpxgeneablationalterslipidraftdomainsinprimaryculturedmousehepatocytess AT nobuyomaeda scp2scpxgeneablationalterslipidraftdomainsinprimaryculturedmousehepatocytess AT annbkier scp2scpxgeneablationalterslipidraftdomainsinprimaryculturedmousehepatocytess AT friedhelmschroeder scp2scpxgeneablationalterslipidraftdomainsinprimaryculturedmousehepatocytess |