SH3BP5 and infection: The first clone, AG18371(RTS)tert1, underwent two phases of almost stationary growth and ceased dividing at 52 PDs post-infection (Fig. 6c) at which time the cells showed an enlarged morphology with high staining for SAβ-gal (see dark patches in Fig. 6g) and a BrdU LI of <5 %, suggesting that these were senescent cells.