Table 1.

Kinetics of externalization of GLUT4myc

Condition	Externalization	Externalization
	t1/2	Total time
Basal	2 h	6 h
Insulin	0.7 h	3 h
Hypertonic sucrose	1.2 h	5 h

L6-GLUT4myc myoblasts were incubated with anti-myc (9E10) antibody at 37°C in the presence or absence of 100 nM insulin or 0.45 M hypertonic sucrose. The amount of GLUT4myc labeled at the cell surface over time was expressed as a percentage of total GLUT4myc content (see Materials and Methods). The externalization t_1/2 denotes the time (hours) taken for one-half of the total GLUT4myc protein to be labeled at the plasma membrane by 9E10 antibody. The total externalization time denotes the time (hours) taken for all of the cellular GLUT4myc protein to be labeled by 9E10 antibody.