Positive regulator of protein phosphatase SIT4. Involved in directing expression of TOR-repressed genes and in dephosphorylation of NPR1 in response to nutrient starvation. Negatively modulates K(+) efflux of the cell by the Na(+)-K(+)/H(+) antiporter NHA1. Associates with the SIT4 protein phosphatase catalytic subunit in a cell-cycle-dependent manner. Hyperphosphorylated in the absence of SIT4. Present with 5960 molecules/cell in log phase SD medium. Belongs to the SAPS family.