3.2.2.28	cell culture	poorly expressed in exponentially growing cells. Mug is overexpressed as cells enter stationary phase, and it is maintained at a fairly high level in resting cells. This is true of cells grown in rich or minimal media, and the principal regulation of mug is at the level of mRNA. Although the expression of mug is strongly dependent on the stationary-phase sigma factor, when cells are grown in minimal media, it shows only a modest dependence on stationary-phase sigma factor when cells are grown in rich media	694210