Abstract |
Phosphorylation and activation of caspases play an important role in the induction of apoptosis. During tumor specific apoptosis, induced by the human monoclonal antibody SC-1, tyrosine phosphorylation and serine dephosphorylation of several proteins is observed. In this paper we describe the identification of two dephosphorylated proteins as heterogeneous nuclear ribonucleoproteins A1 and A2 ( hnRNP A1, hnRNP A2). The dephosphorylation of these proteins is important for apoptosis since the amount of apoptotic cell death can be decreased by the specific serine/threonine phosphatase inhibitor okadaic acid. We also investigated the effect of serine kinase inhibitor H7 on SC-1 induced apoptosis, which leads to a dose dependent increase in apoptosis. We could also show that 24 hours after the induction of apoptosis the hnRNP A1 protein is cleaved into different cleavage products. Further, we found a decreased expression of caspase-2 in early apoptosis signalling and an overexpression 24 hours after induction of apoptosis. Our results show that the phosphorylation status of the hnRNP A1 and A2 plays a significant role in early SC-1 induced apoptosis signalling and further indicate the role of caspase activation during the apoptotic process.
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Authors | R Hermann, F Hensel, E C Müller, M Keppler, M Souto-Carneiro, S Brändlein, H K Müller-Hermelink, H P Vollmers |
Journal | Human antibodies
(Hum Antibodies)
Vol. 10
Issue 2
Pg. 83-90
( 2001)
ISSN: 1093-2607 [Print] Netherlands |
PMID | 11673663
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Antibodies, Monoclonal
- Antibodies, Monoclonal, Humanized
- DNA, Complementary
- Heterogeneous Nuclear Ribonucleoprotein A1
- Heterogeneous-Nuclear Ribonucleoprotein Group A-B
- Heterogeneous-Nuclear Ribonucleoproteins
- Ribonucleoproteins
- SC-1 monoclonal antibody
- hnRNP A2
- Caspase 2
- Caspases
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Topics |
- Amino Acid Sequence
- Antibodies, Monoclonal
(immunology)
- Antibodies, Monoclonal, Humanized
- Apoptosis
(immunology)
- Caspase 2
- Caspases
(metabolism)
- DNA, Complementary
- Heterogeneous Nuclear Ribonucleoprotein A1
- Heterogeneous-Nuclear Ribonucleoprotein Group A-B
- Heterogeneous-Nuclear Ribonucleoproteins
- Humans
- Hydrolysis
- Phosphorylation
- Reverse Transcriptase Polymerase Chain Reaction
- Ribonucleoproteins
(antagonists & inhibitors, metabolism)
- Spectrometry, Mass, Electrospray Ionization
- Stomach Neoplasms
(immunology)
- Tumor Cells, Cultured
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