In the RISC, the RNA-induced silencing complex along with DICER, two proteins, Arb1 and Arb2, both of which are required for histone H3 Lys9 (H3-K9) methylation, heterochromatin assembly and siRNA generation. Arb1 and Arb2 inhibit the release of the siRNA passenger strand from Ago1.
Buker, S.M., Iida, T., Buhler, M., Villen, J., Gygi, S.P., Nakayama, J., and Moazed, D. (2007). Two different Argonaute complexes are required for siRNA generation and heterochromatin assembly in fission yeast. Nat Struct Mol Biol 14, 200-207.
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