Politz JC, Tuft RA, Prasanth KV, Baudendistel N, Fogarty KE, Lifshitz LM, Langowski J, Spector DL, Pederson T. Rapid, diffusional shuttling of poly(A) RNA between nuclear speckles and the nucleoplasm. Mol Biol Cell. 2006 Mar; 17(3):1239-49.