Inhibition of poly(ADP-ribose) polymerase activity by Bcl-2 in association with the ribosomal protein S3a.
We screened a human lymphocyte cDNA library using the yeast two-hybrid system and an automodification domain of PARP as a probe. The DNA sequence of an isolated clone (clone 3-9) was identical to the partial cDNA sequence of the human ribosomal protein S3a. We confirmed that PARP interacts with clone 3-9 by performing binding studies using a GST-3-9 fusion protein as bait. We also demonstrated that native S3a in nuclear extracts of HL-60 cells interacts with the automodification domain of PARP and that PARP from nuclear extracts is coprecipitated with the GST-3-9 fusion protein. Furthermore, we demonstrated that Bcl-2 interacts with PARP in association with S3a and that the interaction of S3a and Bcl-2 with PARP causes a significant decrease in PARP activity. Since Bcl-2 failed to inhibit PARP activity in the absence of S3a, we suggest that Bcl-2 together with S3a prevents apoptosis probably by inhibiting PARP activity.
Song
Demao
D
Laboratory of Molecular Biology, Medical Research Center, Kochi Medical School, Kochi 783-8505, Japan.
Sakamoto
Shuji
S
Taniguchi
Taketoshi
T
D000906:Antibodies; D018076:DNA, Complementary / Q000378:metabolism; D004926:Escherichia coli; D015723:Gene Library; D005982:Glutathione Transferase / Q000378:metabolism; D006801:Humans; D008214:Lymphocytes / Q000378:metabolism; D010957:Plasmids; D000067856:Poly(ADP-ribose) Polymerase Inhibitors; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000276:immunology / Q000378:metabolism; D012269:Ribosomal Proteins / Q000378:metabolism*; D013917:Thrombin / Q000378:metabolism
D000906:Antibodies; D018076:DNA, Complementary; D000067856:Poly(ADP-ribose) Polymerase Inhibitors; D019253:Proto-Oncogene Proteins c-bcl-2; C031016:RPS3A protein, human; D011993:Recombinant Fusion Proteins; D012269:Ribosomal Proteins; D005982:Glutathione Transferase; D013917:Thrombin