Cleavage of 14-3-3 protein by caspase-3 facilitates bad interaction with Bcl-x(L) during apoptosis.
The 14-3-3 epsilon protein was identified as one of the caspase-3 substrates by the modified yeast two-hybrid system. The cellular 14-3-3 epsilon protein was also cleaved in response to the treatment of apoptosis inducers in cultured mammalian cells. Asp238 of the 14-3-3 epsilon protein was determined as the site of cleavage by caspase-3. The affinity of the cleaved 14-3-3 mutant protein (D238) to Bad, a death-promoting Bcl-2 family protein, was lower than that of wild type or the uncleavable mutant 14-3-3 epsilon protein (D238A). However, Bad associated with the cellular Bcl-x(L) more effectively in human 293T cells co-expressing Bad with the truncated form of the 14-3-3 epsilon protein (D238) than in control cells co-expressing Bad with wild type or the uncleavable mutant 14-3-3 epsilon protein (D238A). The present study suggests that the cleavage of 14-3-3 protein during apoptosis promotes cell death by releasing the associated Bad from the 14-3-3 protein and facilitates Bad translocation to the mitochondria and its interaction with Bcl-x(L).
Won
Jungyeon
J
Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Taejon 305-701, South Korea.
Kim
Doo Yeon
DY
La
Muhnho
M
Kim
Doyeun
D
Meadows
Gary G
GG
Joe
Cheol O
CO
D048948:14-3-3 Proteins; D000818:Animals; D017209:Apoptosis; D001665:Binding Sites; D001692:Biological Transport; D019556:COS Cells; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D020170:Caspase 1 / Q000378:metabolism; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism*; D004789:Enzyme Activation; D005434:Flow Cytometry; D015870:Gene Expression; D006801:Humans; D015151:Immunoblotting; D007163:Immunosorbent Techniques; D008928:Mitochondria / Q000378:metabolism; D016297:Mutagenesis, Site-Directed; D011506:Proteins / Q000235:genetics / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D011993:Recombinant Fusion Proteins; D012441:Saccharomyces cerevisiae / Q000235:genetics; D014162:Transfection; D020798:Two-Hybrid System Techniques; D014446:Tyrosine 3-Monooxygenase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D051025:bcl-Associated Death Protein; D051020:bcl-X Protein
D048948:14-3-3 Proteins; C494819:BAD protein, human; C494811:BCL2L1 protein, human; D002352:Carrier Proteins; D011506:Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D011993:Recombinant Fusion Proteins; D051025:bcl-Associated Death Protein; D051020:bcl-X Protein; D014446:Tyrosine 3-Monooxygenase; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases; D020170:Caspase 1