Aggregated DsRed-Tagged Cx43 and Over-Expressed Cx43 are Targeted to Lysosomes in Human Breast Cancer CellsCell Communication and Adhesion (2001)
AbstractTo investigate if either wild-type or aggregated Cx43 is abnormally targeted to lysosomes in human breast tumor cells, we examined the fate of DsRed-tagged Cx43 and over-expressed Cx43 in communication-deficient HBL-100 and MDA-MB-231 cells. DsRed-tagged Cx43 was assembled into gap junctions in control normal rat kidney cells that express endogenous Cx43 but not in Cx43-negative HBL-100 cells. However, when HBL-100 cells were engineered to coexpress wild-type Cx43 a population of DsRed-tagged Cx43 was rescued and assembled into gap junctions. Co-expression of wild-type Cx26 failed to rescue the assembly of DsRed-tagged Cx43 into gap junctions. Immunolocalization studies revealed that DsRed-tagged Cx43 was aggregated and partially localized to lysosomes. Interestingly, when human MDA-MB-231 breast tumor cells over-expressed wild-type Cx43, Cx43 protein primarily localized to lysosomes. Together, these studies provide evidence for Cx43 being targeted to lysosomes as a result of misfolding and aggregation, while in other cases, the delivery of wild-type Cx43 to lysosomes appears to be due to defects innate to the breast tumor cell type.
- gap junctions,
Citation InformationH. Qin, Q. Shao, Daniel Belliveau and D. W. Laird. "Aggregated DsRed-Tagged Cx43 and Over-Expressed Cx43 are Targeted to Lysosomes in Human Breast Cancer Cells" Cell Communication and Adhesion Vol. 8 (2001)
Available at: http://works.bepress.com/daniel_belliveau/7/