Fig. 3.
Poorly structured 3′ UTRs increase RNA stability to enhance transcript accumulation. a qRT-PCR assays showed the relative expression of LUC (left) and F-box (right) in different transgenic samples (PCHR2-LUC-3′ UTR, PCHR2-LUC-pri-miR159a-3′ UTR, and PCHR2-LUC-pri-miR159a-T1-3′ UTR) collected at indicated times after the treatment with 50 μM Act D. Half-life t1/2 (h) is shown. LUCCK t1/2 < LUC159a/159a-T1 t1/2. F-boxCK t1/2 ≅ F-box159a/159a-T1 t1/2. RNA was extracted from 10-day-old seedlings of each line. The relative expression of tested genes was normalized to that of 18S rRNA. b qRT-PCR showed the relative mRNA abundance of in vitro transcribed 3′ end region of LUC transcripts of PCHR2-LUC-3′ UTR (CK-3′ UTR) and PCHR2-LUC-pri-miR159a-T1-3′ UTR (pri-miR159a-T1-3′ UTR) delivered into Col-0, sov, and xrn4. The same level of in vitro transcripts was infiltrated into 10-day-old Col-0, xrn4, and sov seedlings, respectively. Infiltrated plants were collected at indicated time points for qRT-PCR. A different in vitro transcribed segment of LUC transcript was co-infiltrated as a reference for normalization. c qRT-PCR showed that the decay of LUC transcripts with highly structured 3′ UTRs is through SOV and XRN4. Ten-day-old seedlings were treated with 50 μM Act D for indicated times before sampling. The relative expression of LUC was normalized to that of 18S rRNA. Data from a–c are shown as means ± SE from three independent biological replicates. ns, no significance; *P < 0.05; **P < 0.01; unpaired two-tailed Student’s t test