Fig. 4

Roquin1 destabilized the mRNAs of cell cycle–promoting genes via the ROQ domain. a–d MDA-MB-468 cells overexpressing Roquin1/GFP protein were added with ActD and DRB for different time points. The levels of remaining cell cycle–promoting gene transcripts, including CCND1 (a), CCNE1 (b), CDK6 (c), and MCM2 (d), were measured by qPCR. e Schematic representation of the ROQ, RING, zinc finger (ZF), and PRD domains in Roquin1, and their truncations: aa 1–441, aa 441–1133, and aa 174–326. f Expression of Roquin1/GFP and its truncated mutations were confirmed by immunoblotting with an anti-GFP antibody. g MDA-MB-468 cells were transiently transfected with Roquin1 and its mutants. After 36 h, total RNA was extracted to measure the mRNA expression of indicated genes by qPCR. h HEK293 cells were co-transfected with indicated reporters and Roquin1 as well as its truncations. After 36 h, luciferase activity was measured in cell lysates and compared with that cells transfected with empty vector. i Cell counting was conducted in MDA-MB-468 cells after overexpressing Roquin1 and its mutants (n = 3). ***P < 0.0001. j Cell cycle was examined by FCM in MDA-MB-468 cells after overexpressing Roquin1 and its mutants (n = 3). *P < 0.05