Arabidopsis ARGONAUTE7 selects miR390 through multiple checkpoints during RISC assembly

作者：Endo Yayoi; Iwakawa Hiro oki^*; Tomari Yukihide

来源：EMBO Reports, 2013, 14(7): 652-658.

DOI：10.1038/embor.2013.73

• Argonaute
• microRNA
• RISC

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.

• 出版日期2013-6