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Arabidopsis ARGONAUTE7 selects miR390 through multiple checkpoints during RISC assembly.

ABSTRACT: Plant ARGONAUTE7 (AGO7) assembles RNA-induced silencing complex (RISC) specifically with miR390 and regulates the auxin-signalling pathway via production of TAS3 trans-acting siRNAs (tasiRNAs). However, how AGO7 discerns miR390 among other miRNAs remains unclear. Here, we show that the 5' adenosine of miR390 and the central region of miR390/miR390* duplex are critical for the specific interaction with AGO7. Furthermore, despite the existence of mismatches in the seed and central regions of the duplex, cleavage of the miR390* strand is required for maturation of AGO7-RISC. These findings suggest that AGO7 uses multiple checkpoints to select miR390, thereby circumventing promiscuous tasiRNA production.

SUBMITTER: Endo Y

PROVIDER: S-EPMC3701240 | biostudies-literature | 2013 Jul

REPOSITORIES: biostudies-literature

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Arabidopsis ARGONAUTE7 selects miR390 through multiple checkpoints during RISC assembly.

Endo Yayoi Y Iwakawa Hiro-oki HO Tomari Yukihide Y

EMBO reports 20130604 7

Plant ARGONAUTE7 (AGO7) assembles RNA-induced silencing complex (RISC) specifically with miR390 and regulates the auxin-signalling pathway via production of TAS3 trans-acting siRNAs (tasiRNAs). However, how AGO7 discerns miR390 among other miRNAs remains unclear. Here, we show that the 5' adenosine of miR390 and the central region of miR390/miR390* duplex are critical for the specific interaction with AGO7. Furthermore, despite the existence of mismatches in the seed and central regions of the d ...[more]

PMID: 23732541

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