Figure 1.

Rfp2 is an unstable protein that becomes stabilized with proteasomal inhibition. (A) HEK293 cells were transfected with GST-tagged Rfp2, Dltet, and empty vector, and exogenous protein expression was detected with monoclonal antibodies against GST. (B) Steady state levels of transfected FLAG-tagged Rfp2 in HEK293 cells after treatment with 30 μM MG-132 for 4 h. Rfp2 protein was detected with FLAG antibodies. Asterisks indicate Rfp2 conjugated with single ubiquitin molecules (see below). Actin and tubulin were used as loading controls as indicated. Numbers indicate protein size in kDa.