Fig. 2
From: Conserved and highly expressed tRNA derived fragments in zebrafish
Quantification of four different tRFs by northern blot analysis. Total RNA was extracted from samples corresponding to different zebrafish developmental stages [24 h post fertilization (hpf), 48, 72, 96 hpf] and from samples of different zebrafish adult tissues, namely brain, fins, muscle and skin. 20 μg of total RNA from each sample was electrophoresed on 10 % PAA gels and transferred onto Hybond-N membranes for northern blot analysis. tRFs showed high hybridization signal in muscle and skin samples and low hybridization signal in developmental samples. U6 RNA was used as an internal positive control. Relative quantification of the bands corresponding to mature tRNAs and tRFs was carried out using U6 RNA as reference for normalization. Membranes were stripped and reprobed (membrane one was used to perform the following northern blots: 5′tRF- LysTTT, 5′tRF-ProCGG and U6; membrane two was used to perform the following northern blots: 5′tRF-GluCTC, 3′tRF-ProAGG and U6). Ratio between tRF and mature tRNA are indicated under the bars of each sample. a 5′tRF-LysTTT is expressed in adult tissues only. b 5′tRF-GluCTC is highly expressed in muscle and skin tissues. At 24 hpf, the level of mature tRNA is almost twofold higher than in the other samples. c 5′tRF-ProCGG is more abundant than the mature tRNA in fins, muscle and skin tissues. The expression of this fragment in skin is twofold higher than the mature tRNA. d 3′tRF-ProAGG is expressed at low level and is found in adult tissues only. Data are presented as the mean ± SD (n = 3)