Creagh, E.M., Brumatti, G., Sheridan, C., Duriez, P.J., Taylor, R.C., Cullen, S.P., Adrain, C., Martin, S.J. (2009). Bicaudal is a conserved substrate for Drosophila and mammalian caspases and is essential for cell survival. PLoS ONE 4(3): e5055.
FlyBase ID
FBrf0207682
Publication Type
Research paper
Abstract
Members of the caspase family of cysteine proteases coordinate cell death through restricted proteolysis of diverse protein substrates and play a conserved role in apoptosis from nematodes to man. However, while numerous substrates for the mammalian cell death-associated caspases have now been described, few caspase substrates have been identified in other organisms. Here, we have utilized a proteomics-based approach to identify proteins that are cleaved by caspases during apoptosis in Drosophila D-Mel2 cells, a subline of the Schneider S2 cell line. This approach identified multiple novel substrates for the fly caspases and revealed that bicaudal/betaNAC is a conserved substrate for Drosophila and mammalian caspases. RNAi-mediated silencing of bicaudal expression in Drosophila D-Mel2 cells resulted in a block to proliferation, followed by spontaneous apoptosis. Similarly, silencing of expression of the mammalian bicaudal homologue, betaNAC, in HeLa, HEK293T, MCF-7 and MRC5 cells also resulted in spontaneous apoptosis. These data suggest that bicaudal/betaNAC is essential for cell survival and is a conserved target of caspases from flies to man.