Skip to main content
. 2005 Dec 12;393(Pt 1):59–67. doi: 10.1042/BJ20050674

Figure 5. Immunoelectron localization of Cx43 in early and late endosomes.

Figure 5

(A, B) IAR20 cells were treated with PMA (100 ng/ml) for 30 min. During the last 10 min of incubation, 8 nm BSA–gold particles were added to the medium, to mark early endosomes. Cells were fixed, prepared for electron microscopy and labelled for Cx43 (15 nm gold). Early endosomes, characterized by their electron-lucent appearance, a few internal vesicles and content of 8 nm gold particles, were often found to contain Cx43. Cx43 was found both on the limiting vacuolar membrane and on intravacuolar vesicles. (C, D) To mark both early and late endosomes, cells were treated with PMA (100 ng/ml) for 30 min in a medium containing 8 nm BSA–gold particles. Cells were fixed and labelled for Cx43 (15 nm gold). Cx43 was found in late endosomes, differentiated from early endosomes by their globular form, their more electron-dense appearance and by containing more internal vesicles. Scale bars, 200 nm.