GLUT1 is associated with sphingolipid-organized, cholesterol-independent domains in L929 mouse fibroblast cells.

GLUT1 is associated with sphingolipid-organized, cholesterol-independent domains in L929 mouse fibroblast cells. Biochimie. 2019 Apr 10;: Authors: Rylaarsdam LE, Johnecheck GN, Looyenga BD, Louters LL Abstract Glucose is a preferred metabolite in most mammalian cells, and proper regulation of uptake is critical for organism homeostasis. The glucose transporter 1 (GLUT1) is responsible for glucose uptake in a wide variety of cells and appears to be regulated in a tissue specific manner. Therefore, a better understanding of GLUT1 regulation within its various cellular environments is essential for developing therapeutic strategies to treat disorders associated with glucose homeostasis. Previous findings suggest that plasma membrane subdomains called lipid rafts may play a role in regulation of GLUT1 uptake activity. While studying this phenomenon in L929 mouse fibroblast cells, we observed that GLUT1 associates with a low density lipid microdomain distinct from traditionally-defined lipid rafts. These structures are not altered by cholesterol removal with methyl-ß-cyclodextrin and lack resistance to cold Triton X-100 extraction. Our data indicate that the GLUT1-containing membrane microdomains in L929 cells, as well as GLUT1's basal activity, are instead sphingolipid-dependent, being sensitive to both myriocin and sphingomyelinase treatment. These microdomains appear to be organized primarily by their lipid composition, as disruption ...
Source: Biochimie - Category: Biochemistry Authors: Tags: Biochimie Source Type: research