The molecular amounts of the proteins initially occurring in the PRR model are here expressed as number of molecules per cell. Data in the second column were collected from log phase growing yeast cells, retrieved from the reference database reported in the third column. The amount of ubiquitin is calculated as the sum of molecular amounts deriving from the four genes coding for ubiquitin in yeast cells (namely, UBI1, UBI2, UBI3, UBI4). The fourth column reports the derived nuclear amounts of the proteins that are localized both in the nucleus and in the cytoplasm, scaled according to the 7% fraction of nuclear volume with respect to the total yeast cell volume . This column specifies, in particular, the molecular amounts of proteins occurring in the initial state of the system. The proteins marked with the asterisk (Ubc13, Mms2) occur in the model as complex (Ubc13 : Mms2), whose initial amount is fixed at the minimum value between the amounts of the two proteins (namely, 193 molecules/cell).