@article{833a65ff83f94a739577f4d69cab3356,
title = "Stalled spliceosomes are a signal for RNAi-mediated genome defense",
abstract = "Using the yeast Cryptococcus neoformans, we describe a mechanism by which transposons are initially targeted for RNAi-mediated genome defense. We show that intron-containing mRNA precursors template siRNA synthesis. We identify a Spliceosome-Coupled And Nuclear RNAi (SCANR) complex required for siRNA synthesis and demonstrate that it physically associates with the spliceosome. We find that RNAi target transcripts are distinguished by suboptimal introns and abnormally high occupancy on spliceosomes. Functional investigations demonstrate that the stalling of mRNA precursors on spliceosomes is required for siRNA accumulation. Lariat debranching enzyme is also necessary for siRNA production, suggesting a requirement for processing of stalled splicing intermediates. We propose that recognition of mRNA precursors by the SCANR complex is in kinetic competition with splicing, thereby promoting siRNA production from transposon transcripts stalled on spliceosomes. Disparity in the strength of expression signals encoded by transposons versus host genes offers an avenue for the evolution of genome defense.",
author = "Dumesic, {Phillip A.} and Prashanthi Natarajan and Changbin Chen and Drinnenberg, {Ines A.} and Schiller, {Benjamin J.} and James Thompson and Moresco, {James J.} and Yates, {John R.} and Bartel, {David P.} and Madhani, {Hiten D.}",
note = "Funding Information: We thank members of the Madhani and Guthrie labs, P. O{\textquoteright}Farrell, J. Reuter, and S. Coyle for critical reading of the manuscript and helpful discussions; N. Nguyen for media preparation; and X. Wang and J. Heitman for strains and plasmids. Mass spectrometry experiments were supported by the National Center for Research Resources (5P41RR011823-17), the National Institute of General Medical Sciences (8 P41 GM103533-17), and the National Institute on Aging (R01AG027463-04). P.A.D. and H.D.M. designed the study. C.C., I.A.D., and D.P.B. performed high-throughput sequencing shown in Figure 1 . J.T., J.J.M., and J.R.Y. performed mass spectrometry analyses shown in Figures 2 , 3 , and 4 . P.N. performed subcellular localization of tagged proteins shown in Figures 2 , 3 , 4 , and S1 . B.J.S. performed bioinformatic analyses shown in Figures 1 , 5 , and 7 and Tables S1 and S2 . P.A.D. performed experiments shown in Figures 2 , 3 , 4 , 5 , 6 , 7 , S2 , S3 , and S4 . P.A.D. and H.D.M. wrote the manuscript. All authors contributed to editing the manuscript. ",
year = "2013",
month = feb,
day = "28",
doi = "10.1016/j.cell.2013.01.046",
language = "English (US)",
volume = "152",
pages = "957--968",
journal = "Cell",
issn = "0092-8674",
publisher = "Cell Press",
number = "5",
}