Prediction of translocation and cleavage of heterogeneous ribonuclear proteins and Rho guanine nucleotide dissociation inhibitor 2 during apoptosis by subcellular proteome analysis.
Jurkat T cells induced to undergo apoptosis by the CD95(Fas/Apo-1) pathway were investigated by proteome analysis. The most prominent differing protein spots of apoptotic and nonapoptotic cells were identified as various heterogeneous ribonuclear proteins (hnRNPs) and Rho guanin nucleotide dissociation inhibitor (GDI) 2. In apoptotic cells, four spots slightly differing in molecular mass and/or isoelectric point were identified as Rho GDI 2 with the mass and pI as expected after caspase-3 cleavage near the N-terminus. Subcellular proteome analysis revealed that Rho GDI 2 was highly enriched in the cytosolic fraction, present in minor amounts in the nuclear fraction and absent from the mitochondrial fraction. In apoptotic cells however, the spots representing processed and modified Rho GDI 2 were found in the cytosol, in the nucleus and also the mitochondria at different spot positions. In addition, twelve different hnRNPs were identified to be altered after induction of cell death of which hnRNPs A/B, D, F, H, I and L were hitherto unknown to be modified during apoptosis. Most of the hnRNP spots were found in the nucleus of nonapoptotic cells, whereas these proteins, either modified or unmodified, relocated to the cytosol and/or the mitochondria in apoptotic cells. Our results demonstrate that modification of proteins during apoptosis is often accompanied by their relocalisation between cellular compartments.
Max Planck Institute for Infection Biology, Department of Molecular Biology, Schumannstrasse 21/22, D-10117 Berlin, Germany.
Bernd
B
Thiede
Frank
F
Siejak
Christiane
C
Dimmler
Thomas
T
Rudel
D021581:Active Transport, Cell Nucleus / Q000502:physiology; D017209:Apoptosis / Q000502:physiology*; D002458:Cell Fractionation; D015180:Electrophoresis, Gel, Two-Dimensional; D020730:Guanine Nucleotide Dissociation Inhibitors / Q000378:metabolism*; D034441:Heterogeneous-Nuclear Ribonucleoproteins / Q000378:metabolism*; D006801:Humans; D019169:Jurkat Cells; D008969:Molecular Sequence Data; D010449:Peptide Mapping; D020543:Proteome / Q000032:analysis*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D025521:Tumor Suppressor Proteins; D020741:rho GTP-Binding Proteins / Q000378:metabolism*; D062949:rho Guanine Nucleotide Dissociation Inhibitor beta; D062947:rho-Specific Guanine Nucleotide Dissociation Inhibitors
C569658:ARHGDIB protein, human; D020730:Guanine Nucleotide Dissociation Inhibitors; D034441:Heterogeneous-Nuclear Ribonucleoproteins; D020543:Proteome; D025521:Tumor Suppressor Proteins; D062949:rho Guanine Nucleotide Dissociation Inhibitor beta; D062947:rho-Specific Guanine Nucleotide Dissociation Inhibitors; D020741:rho GTP-Binding Proteins