Fig. 3
From: Conserved and highly expressed tRNA derived fragments in zebrafish
Embryo and adult profiling of 5′tRF-GluCTC and 5′tRF-ProCGG. 20 μg of total RNA was fractionated in a 10 % PAA and transferred onto Hybond-N membranes for northern blot analysis. U6 RNA was used as an internal positive control. Relative quantification of the bands corresponding to tRFs was carried out using U6 RNA as reference for normalization. The relative expression level (%) was calculated considering that the sample with the highest level of tRF expression corresponded to 100 % of tRF abundance. a Northern blot analysis of 5′tRF-GluCTC and 5′tRF-ProCGG in different developmental stages, namely 24, 48, 72 hpf, 10 days post fertilization (dpf), 1 month post fertilization (mpf) and 2 mpf. Membrane was stripped and probed with 5′tRF-GluCTC, 5′tRF-ProCGG and U6. The highest level of expression was detected at 2 mpf for both tRFs. 5′tRF-GluCTC expression gradually increased during development. 5′tRF-ProCGG was already detected at 24 hpf and its expression varied slightly through development. b Northern blot analysis of 5′tRF-GluCTC and 5′tRF-ProCGG using samples from different differentiated tissues, namely eyes, brain, gills, bone, muscle, gut, skin and fins. Membrane was stripped and probed with 5′tRF-GluCTC, 5′tRF-ProCGG and U6. 5′tRF-GluCTC was highly expressed in bone, gut, skin and fins and less expressed in brain. The highest level of 5′tRF-ProCGG expression was detected in gills, bone and gut. This tRF was expressed at lower levels in the brain, similarly to 5′tRF-GluCTC. Data are presented as the mean ± SD (n = 3) (Student’s unpaired t test, *P < 0.05, **P < 0.01, ***P < 0.001)