Observing GLUT4 translocation in live L6 cells using quantum dots.
The glucose transporter 4 (GLUT4) plays a key role in maintaining whole body glucose homeostasis. Tracking GLUT4 in space and time can provide new insights for understanding the mechanisms of insulin-regulated GLUT4 translocation. Organic dyes and fluorescent proteins were used in previous studies for investigating the traffic of GLUT4 in skeletal muscle cells and adipocytes. Because of their relative weak fluorescent signal against strong cellular autofluorescence background and their fast photobleaching rate, most studies only focused on particular segments of GLUT4 traffic. In this study, we have developed a new method for observing the translocation of GLUT4 targeted with photostable and bright quantum dots (QDs) in live L6 cells. QDs were targeted to GLUT4myc specifically and internalized with GLUT4myc through receptor-mediated endocytosis. Compared with traditional fluorescence dyes and fluorescent proteins, QDs with high brightness and extremely photostability are suitable for long-term single particle tracking, so individual GLUT4-QD complex can be easily detected and tracked for long periods of time. This newly described method will be a powerful tool for observing the translocation of GLUT4 in live L6 cells.
Institute of Biophysics and Biochemistry, School of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China. phonequ@gmail.com
Feng
F
Qu
Zubin
Z
Chen
Xiaoxuan
X
Wang
Lingfeng
L
Meng
Zhengxing
Z
Wu
Anlian
A
Qu
D000818:Animals; D002460:Cell Line; D002470:Cell Survival; D004705:Endocytosis; D051275:Glucose Transporter Type 4 / Q000378:metabolism*; D049452:Green Fluorescent Proteins / Q000378:metabolism; D007091:Image Processing, Computer-Assisted; D008856:Microscopy, Fluorescence; D021381:Protein Transport; D045663:Quantum Dots; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D013194:Staining and Labeling
D051275:Glucose Transporter Type 4; D011993:Recombinant Fusion Proteins; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins