Are promyelocytic leukaemia protein nuclear bodies a scaffold for caspase-2 programmed cell death?
Promyelocytic leukaemia protein nuclear bodies (PML-NBs) are nuclear structures whose function is still poorly understood. They are implicated in various biological functions, such as viral infection, cellular transformation, innate immunity and growth control, and they might be dynamic hubs sensing stress and DNA damage. Data from PML(-/-) mice suggest that PML-NBs are involved in apoptosis via caspase-independent mechanisms, probably involving p53-dependent and independent pathways. However, the recently demonstrated co-localization of caspase-2 within the PML-NB nuclear structures presents a new paradigm for nuclear cell death. Here, we show that these nuclear structures have a protein known as SP100 that could contain a caspase recruitment domain (CARD). If verified experimentally, this discovery will suggest a mechanism by which caspase-2 could be recruited into the complex and ultimately lead to apoptosis.
Sanchez-Pulido
Luis
L
National Center for Biotechnology, Consejo Superior de Investigaciones Cientificas. C/Darwin n3, 28049, Madrid, Spain.
Valencia
Alfonso
A
Rojas
Ana M
AM
D000595:Amino Acid Sequence; D000818:Animals; D034961:Antigens, Nuclear / Q000378:metabolism; D017209:Apoptosis; D001324:Autoantigens / Q000378:metabolism; D053420:CRADD Signaling Adaptor Protein; D053143:Caspase 2 / Q000378:metabolism*; D022003:Cell Nucleus Structures; D003546:Cysteine Endopeptidases / Q000378:metabolism*; D006801:Humans; D045586:Intranuclear Inclusion Bodies / Q000378:metabolism*; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins / Q000378:metabolism*; D009687:Nuclear Proteins / Q000378:metabolism*; D000071156:Promyelocytic Leukemia Protein; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000378:metabolism*; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D025521:Tumor Suppressor Proteins / Q000378:metabolism*
D034961:Antigens, Nuclear; D001324:Autoantigens; D053420:CRADD Signaling Adaptor Protein; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D000071156:Promyelocytic Leukemia Protein; C495901:TP53 protein, human; D014157:Transcription Factors; D016159:Tumor Suppressor Protein p53; D025521:Tumor Suppressor Proteins; C066642:SP100 protein, human; C070576:PML protein, human; C490360:CASP2 protein, human; D053143:Caspase 2; D003546:Cysteine Endopeptidases