Fig. 3: 2D averages from negatively stained TEM micrographs of the nNE no-transcription sample and the nNE transcription sample.

a, 2D classes with identifiable angles of the nNE no-transcription sample (65 micrographs, 2,502 particles). The 2D averages depict structures with opening angle ranges that go from 63° up to 99°. b, 2D averages of the nNE transcription sample (80 micrographs, 1,903 particles) with classes that depict structures with opening angles ranging from 17° to 77°. c, Comparison of the angle distribution under the condition of transcription and no transcription. Red, distribution of angles in nanoengines deposited on TEM grids that did not undergo transcription (n = 5,135, 189 micrographs, 64.13° ± 20.04°, min = 0.00°, max = 161.11°, median = 67.03°); cyan, distribution of angles in nanoengines that underwent transcription deposited on TEM grids (n = 3,266, 99 micrographs, 56.51° ± 21.79°, min = 0.00°, max = 132.64°, median = 58.43). The angles were measured using the angle measurement tool of ImageJ software (Supplementary Dataset 4, Extended Data Fig. 4 and Supplementary Table 1). Percentages of relative counts were calculated by dividing the counts of each bar (bin width, 3°) by the total amount of data in the population. d, Box-plot of angle distributions for the nanoengines not undergoing transcription (red) and the nanoengines that are engaged in transcription (cyan). ***P = 3 × 10⁻⁵⁷. P values were obtained with a two-tailed, heteroscedastic t-test. Box-plot edges, 25th and 75th percentiles; box lines, 50th percentiles; whisker size, 1.5 × IQR; grey dots, outliers. Error ranges are the mean and s.d.