Fig. 1.

TGase and TGase-S differently impact cell viability. (a) Schematic diagram of the functional domains of TGase (Upper) and TGase-S (Lower). The numbers refer to amino acid residues. (b) Myc-TGase or Myc-TGase-S was expressed in NIH 3T3 cells for various times and then lysed. The cell lysates were immunoblotted as indicated. (c) NIH 3T3 cells transiently expressing Myc-TGase or Myc-TGase-S were maintained in medium with or without 5% serum for 1 day and then fixed. Immunofluorescence was performed on the samples by using Myc antibody and DAPI to detect transfectants and nuclei, respectively (Inset). Cells cultured with (open bars) or without (filled bars) serum were scored for cell death as identified by nuclear condensation/blebbing and graphed. (d) SKBR3 cells expressing Myc-TGase or Myc-TGase-S for 2 days were assayed for cell death as outlined in c.