Skip to main content
. 2013 Aug 13;2(8):e115. doi: 10.1038/mtna.2013.40

Figure 4.

Figure 4

Evaluation of mTOR activity in UOK257-FS and UOK257 cells under serum-starved conditions. Protein levels of mTOR, Raptor, p70-S6 (Thr389), pS6R (Ser235/236) and p4E-BP1 of both cell lines were determined by Western analysis under normal serum (S+) and serum-deprived conditions (S-) as shown by the compilation of Western blots. A portion of UOK257-FS cells was stimulated with serum again following serum starvation (S++). Under normal serum conditions (S+), no differences in mTOR activity is detected between UOK257-FS (1) and UOK257 cells (2). Following serum-deprivation for 48 hours (S-), loss of mTOR signaling is detected in the FLCN-restored UOK257-FS cells (3), indicated by loss of p4E-BP1 signal. Re-establishment of 4E-BP1 phosphorylation is seen following restoration of serum for 48 hours (S++) in UOK257-FS cells (5). Under serum-starved conditions (S-) no suppression of mTOR activity is detected in UOK257 cells (4) with an increase in the α-isoform of p4E-BP1.