Long-lived microRNA–Argonaute complexes in quiescent cells can be activated to regulate mitogenic responses

• DOI: 10.1073/pnas.1219958110
• Publication Date: 2012-12-18T05:24:36Z
• Authors: Scott H. Olejniczak; Gaspare La Rocca; Joshua J. Gruber; Craig B. Thompson
• Keywords: Argonaute; RNA-induced silencing complex

Cellular proliferation depends on the integration of mitogenic stimuli with environmental conditions. Increasing evidence suggests that microRNAs play a regulatory role in this integration. Here we show during periods cellular quiescence, mature are stabilized and stored Argonaute protein complexes can be activated by stimulation to repress mitogen-stimulated targets, thus influencing subsequent responses. In quiescent cells, majority exist low molecular weight, protein-containing devoid essential components RNA-induced silencing complex (RISC). For at least 3 wk, pool Argonaute-associated is stable recruited into RISC stimulation. Using several model systems, demonstrate protein-associated small RNAs capable repressing mitogen-induced transcripts. Therefore, may represent previously unappreciated form memory allows cells retain posttranscriptional information over extended quiescence.