Figure 5.

Impaired de novo PtdCho synthesis does not affect cell cycle progression. HeLa cells were transfected with siRNAs targeting CTα or a Non-Targeting pool (NT) at 10 nM for 48 h. The levels of CTα, Cyclin B1 and Vinculin were estimated by Western Blot (a). The level on CTα (b) and cell cycle distribution (d) were assessed in HeLa cells transfected with siRNA targeting CTα (hCTα4) or NT 10 nM for 48 h and incubated for 1 h with 10 μM BrdU. Alternatively, NT and hCTα4-siRNA transfected cells were incubated with [Methyl-3H]choline for 4 h. Aqueous metabolites were resolved by TLC and scrapped off and counted. CTα activity was estimated by the ratio of radiolabeled CDP-Choline/phospho-choline (c). Ct: untransfected cells.