کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
2132413 | 1086688 | 2007 | 10 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: SAFB re-distribution marks steps of the apoptotic process SAFB re-distribution marks steps of the apoptotic process](/preview/png/2132413.png)
We have found novel functions of scaffold attachment factor-B1 (SAFB) during apoptosis. The experiments showed that SAFB moved into the nucleolus 15 min after the induction of apoptosis and before the release of cytochrome c into the cytoplasm. Two hours later SAFB formed a peri-nucleolar ring-like structure and this occurred after cytochrome c release and before PARP cleavage. Digestion with RNase suggested that the peri-nucleolar ring structure was dependent on RNA integrity and a RNA moiety formed part of this structure. Studies using SAFB deletion mutants showed that the formation of the peri-nucleolar structure was not mediated by the DNA binding (SAP) or the RNA binding (RRM) domain of SAFB but was instead dependent on the S/K and R/E coiled-coil regions: a result suggesting that the structure is formed via protein interactions. In addition, SAFB cleavage was shown to be mediated by caspase-3 and occurred after the formation of the peri-nucleolar ring and after cleavage of PARP (characteristic of proteins having a direct role in apoptosis). A determinant for this cleavage is located in the DNA binding domain and we hypothesize that SAFB may direct the reorganization and segregation of nuclear RNA and DNA prior to endonuclease-mediated DNA cleavage.
Journal: Experimental Cell Research - Volume 313, Issue 18, 1 November 2007, Pages 3914–3923