Madin Darby bovine kidney cell synchronization by lovastatin: application to bovine herpesvirus-1 gene expression

The number of investigations involving cell proliferation has increased rapidly in the last years. One of the major difficulties in studying cell-cycle-related events is obtaining highly synchronous cell populations without metabolic imbalance. This study demonstrates that the Madin Darby bovine kidney (MDBK) cells, a commonly used cell line in veterinary research, can be effectively synchronized using lovastatin (Lov), a drug used to treat hypercholesteremia in humans. This was demonstrated by the following results: (i) Lov inhibits cell proliferation in a dose-dependent manner; (ii) Lov synchronizes MDBK cells mainly in the G1 and secondarily in the G2+M cell-cycle phases; (iii) the cytostatic effect of Lov can be specifically inhibited by addition of mevalonate (Mev) (Lov inhibits the synthesis of Mev); (iv) removal of Lov from G1-arrested cultures, followed by addition of Mev, resulted in the synchronous recovery of DNA synthesis; and (v) 5-bromo2'-deoxyuridine incorporation experiments revealed that MDBK cells synchronization by Lov can be followed for at least 3 cycles after removal of Lov and addition of Mev. Furthermore, as an application of investigations based on the availability of synchronized MDBK, we showed that bovine herpesvirus-1 gene expression is independent on the cell cycle.