Analysis of LRAT and Rpe65 Expressed in 293T Cell Lines
(A) Immunoblot analysis of homogenates from 293T-LRC cells transiently transfected with pLRAT or pRPE65 using antisera against LRAT or Rpe65. Homogenates from nontransfected 293T-LRC and 293T cells were also analyzed. Note the stronger LRAT and Rpe65 immunoreactivity in homogenates from transiently transfected 293T-LRC cells.
(B) In vitro isomerase activity of homogenates from 293T-RC and 293T-LRC cells transfected with pRK5 or pRPE65. Substrates were atROL or atRP, as indicated. Histograms show 11cROL peak areas from HPLC chromatograms acquired at 318 nm. Error bars show standard deviations (n = 4). Note the absence of isomerase activity in pRPE65-transfected 293T-RC cell homogenates using atROL as substrate and the presence of activity in the same cells using atRP as substrate. Also note the presence of isomerase activity in pRPE65-transfected 293T-LRC cell homogenates using both atROL and atRP as substrate. Finally, note the reduced synthesis of 11cROL from atRP substrate in 293T-LRC, which express LRAT, versus 293T-RC cells, which do not.