sentence: CycG protein was immuno-precipitated from Schneider S2 cells using guinea pig anti-CycG antibodies as described by Fischer et al. and references therein.16 For detection either rat anti-CycG , rat anti-PP2A-29B or rat anti-Mts ( kind gift of T. Uemura ) or rat anti-Wdb was used.16 ,34,36 Quantitative yeast 2 hybrid studies were performed according to Guarente.37 Miller units are calculated from the ratio of substrate turnover to cell density ( 1000x OD / time [ min ] x volume [ ml ] x OD ) .