Solution structure of the CIDE-N domain of CIDE-B and a model for CIDE-N/CIDE-N interactions in the DNA fragmentation pathway of apoptosis.
Lugovskoy, A.A., Zhou, P., Chou, J.J., McCarty, J.S., Li, P., Wagner, G.(1999) Cell 99: 747-755
- PubMed: 10619428 
- DOI: https://doi.org/10.1016/s0092-8674(00)81672-4
- Primary Citation of Related Structures:  
1D4B - PubMed Abstract: 
Apoptotic DNA fragmentation and chromatin condensation are mediated by the caspase-activated DFF40/ CAD nuclease, which is chaperoned and inhibited by DFF45/ICAD. CIDE proteins share a homologous regulatory CIDE-N domain with DFF40/CAD and DFF45/ ICAD. Here we report the solution structure of CIDE-N of human CIDE-B. We show that the CIDE-N of CIDE-B interacts with CIDE-N domains of both DFF40 and DFF45. The binding epitopes are similar and map to a highly charged bipolar surface region of CIDE-B. Furthermore, we demonstrate that the CIDE-N of CIDE-B regulates enzymatic activity of the DFF40/ DFF45 complex in vitro. Based on these results and mutagenesis data, we propose a model for the CIDE-N/ CIDE-N complex and discuss the role of this novel bipolar interaction in mediating downstream events of apoptosis.
Organizational Affiliation: 
Committee on Higher Degrees in Biophysics, Harvard University, Cambridge, Massachusetts 02138, USA.