TY - JOUR
T1 - Compartmentalization of phosphatidylinositol 4,5-bisphosphate in low-density membrane domains in the absence of caveolin
AU - Liu, Yimin
AU - Casey, Laurieann
AU - Pike, Linda J.
PY - 1998/4/28
Y1 - 1998/4/28
N2 - In cells that exhibit caveolae, the hormone-sensitive pool of PtdIns 4,5-P2 is localized in a low density, caveolin-enriched membrane fraction (1). Neuro 2a cells do not express caveolin. Nonetheless, the PtdIns 4,5-P2 in these cells is compartmentalized in a low density, detergent-insoluble domain that also contains other signaling-related molecules. Compartmentalization of PtdIns 4,5-P2 was observed regardless of whether Triton X-100-containing or detergent-free methods were used to prepare the membranes. However, the partitioning of receptor tyrosine kinases and GPI-anchored proteins into the low density domains was dependent upon the method of membrane preparation. Treatment of Neuro 2a cells with cyclodextrin delocalized the PtdIns 4,5-P2 and inhibited hormone-stimulated PtdIns turnover. These results suggest that compartmentalization of PtdIns 4,5-P2 does not require caveolin but is necessary for the proper functioning of phosphoinositide-based signaling.
AB - In cells that exhibit caveolae, the hormone-sensitive pool of PtdIns 4,5-P2 is localized in a low density, caveolin-enriched membrane fraction (1). Neuro 2a cells do not express caveolin. Nonetheless, the PtdIns 4,5-P2 in these cells is compartmentalized in a low density, detergent-insoluble domain that also contains other signaling-related molecules. Compartmentalization of PtdIns 4,5-P2 was observed regardless of whether Triton X-100-containing or detergent-free methods were used to prepare the membranes. However, the partitioning of receptor tyrosine kinases and GPI-anchored proteins into the low density domains was dependent upon the method of membrane preparation. Treatment of Neuro 2a cells with cyclodextrin delocalized the PtdIns 4,5-P2 and inhibited hormone-stimulated PtdIns turnover. These results suggest that compartmentalization of PtdIns 4,5-P2 does not require caveolin but is necessary for the proper functioning of phosphoinositide-based signaling.
UR - http://www.scopus.com/inward/record.url?scp=0032576969&partnerID=8YFLogxK
U2 - 10.1006/bbrc.1998.8329
DO - 10.1006/bbrc.1998.8329
M3 - Article
C2 - 9588175
AN - SCOPUS:0032576969
SN - 0006-291X
VL - 245
SP - 684
EP - 690
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
IS - 3
ER -