Fig. 3: Bulkiness of RG4 drives translational enhancement.

a Potential G-quadruplex sequence (PQS) candidates with varying loop lengths, representing RNA G-quadruplex (RG4) in RNA. The core domain of guanine triplets (black) remains constant, and loop sequences (highlighted in red) are varied. The sequences are arranged from shortest to longest loop length, indicating an increase of bulkiness. b Real-time GFP signal measurements of individual PQS candidates by plate reader. Non-template (NT), Template (T), and control (C) are colored in blue, purple, and gray, respectively. The curves shown are one representative result from multiple independent experiments. c Normalized translation efficiencies are calculated from the early linear part of curve in (b). The numbers on the x-axis represent the PQS ordered as shown in (a). NT constructs with longer loop lengths, representing bulkier RG4 structures, resulted in higher translation efficiencies. d The correlation between translation efficiency and total loop length. The loop length is the sum of the uridine bases in (a). The correlation coefficients are 0.88 and 0.36 for NT and T, respectively, indicating a strong correlation between translation efficiency and RG4 for NT. Data are presented as mean ± SEM of n = 3–5 and three independent experiments for NT and T, respectively. Exact mean values are provided in Supplementary Table 3.3. Raw data points are provided as a Source Data file. Shown in (c) only represents the significance between template and non-template, where **P < 0.005 (two-sided unpaired t test).