Gene or accession: CG4319 Gene annotation error Gene rpr and fas not homologs has a mistake in the supporting evidence or functional assignment. Comments: The report states that reaper and fas are homologs. This is highly unlikely. The proposition that RPR might represent an ancestral member of 'death domain' containing proteins and, as such, could share functions in common with death receptors (Cleveland and Ihle, 1995; Golstein et al., 1995; Golstein et al., 1995) was not supported by studies in vivo (Chen et al., 1996; Vucic et al., 1997). The lack of a homologous relationship between REAPER and of 'death domain' containing proteins was further bolstered by the recent structural determination of a death domain (Huang et al., 1996; Liang and Fesik, 1997). References Chen, P., Lee, P., Otto, L., and Abrams, J. M. (1996). Apoptotic activity of REAPER is distinct from signalling by the tumor necrosis factor receptor 1 death domain. J. Biol. Chem. 271, 25735-25737. Cleveland, J. L., and Ihle, J. N. (1995). Contenders in FasL/TNF death signaling. Cell 81, 479-82. Golstein, P., Marguet, D., and Depraetere, V. (1995). Fas bridging cell death and cytotoxicity: the reaper connection. Immunol. Rev. 146, 45-56. Golstein, P., Marguet, D., and Depraetere, V. (1995). Homology between Reaper and the cell death domains of Fas and TNFR1. Cell 81, 185-186. Huang, B., Eberstadt, M., Olejniczak, E. T., Meadows, R. P., and Fesik, S. W. (1996). NMR structure and mutagenesis of the Fas (APO-1/CD95) death domain. Nature 384, 638-41. Liang, H., and Fesik, S. W. (1997). THREE-DIMENSIONAL STRUCTURES OF PROTEINS INVOLVED IN PROGRAMMED CELL DEATH Review. Journal of Molecular Biology 274, 291-302. Vucic, D., Seshagiri, S., and Miller, L. K. (1997). Characterization of reaper- and fadd-induced apoptosis in a lepidopteran cell line. Molecular & Cellular Biology 17, 667-676.