Transcriptome profiling of differentiated lenses through RNA sequencing

Objective: To gain insight into the transcriptional landscape including mRNA, long non-coding RNA (lncRNA), and circular RNA (circRNA) of the differentiated lens. Methods: Experiment research. The total RNAs of the differentiated lenses were extracted and purified. Total RNAs of 16-week, 23-week, and 25-week differentiated lenses were then sequenced using Illumina HiSeq 2500, and analyzed using bioinformatics tools. The top expressed and differentially expressed mRNAs and lncRNAs were screened. The expressions of overlap genes among the 16-week, 23-week, and 25-week lenses were analyzed by Venn diagram. The expression tendency of lens-specific genes was obtained and verified with real-time polymerase chain reaction. Results: A total of 67 518 311 mapped reads were obtained from differentiated lenses at 16 weeks, 99 440 160 at 23 weeks, and 67 262 320 at 25 weeks. The gene overlap expression analysis showed 740 of the top 1 000 highly expressed mRNAs, 170 of the top 300 highly expressed lncRNAs, and 69 of the top 100 highly expressed circRNAs overlapping expressed in lenses at 16, 23, and 25 weeks, respectively. Lens specific gene expression analysis revealed that the expression of crystallin (CRY) AA, CRYGA, CRYGB, CRYGC, CRYGD, CRYGEP, and CRYGS was upregulated, while the expression of gap junction (GJ) A3 and GJA8 was downregulated with the differentiation of lenses. Conclusion: The lens transcriptome profile shows that more than half of the high expressed mRNA, lncRNA and circRNA at different differentiation stages are overlapping expressed, and all of them have high expression of lens specific protein genes, such as CRY, GJ etc. (Chin J Ophthalmol, 2020, 56: 356-363).