Figure 6.

LMP1 deregulates integrin subunit expression. (A) RT-PCR confirmed the upregulation of α5 integrin subunit, as well as urokinase plasminogen activator (uPA) and its receptor, uPAR in wildtype and CTAR1+/2− LMP1-expressing cells; (B) Flow cytometric analysis confirmed an increase in basal levels of α5 integrin expression on the cell surface of LMP1-expressing cells, but very little increase in basal levels of β1 integrin. Using an antibody that specifically recognises β1 integrin in its active conformation demonstrated an increase in β1 integrin activation on the cell surface of LMP1-expressing cells. This was unaffected by inhibition of ERK-MAPK signalling, since addition of 60 μM UO126 had no significant effect on cell surface expression of these integrin subunits, active or otherwise.