The effects of METTL3 on islet β-cell function

Purpose: The goal of this study is to investigate how METTL3 regulates islet β-cell function. Methods: Total RNA was extracted using Tripure Isolation Reagent (Roche, Mannheim, Germany) from pancreatic islets of Mettl3flox/flox and β-Mettl3-KO mice at 8 weeks old. Each RNA sample was pooled from four Mettl3flox/flox and β-Mettl3-KO mice, respectively. Three independent biological replicates for each group were used for RNA-seq. RNA-seq was performed by deep sequencing using an Illumina Novaseq 6000 platform. Paired-end clean reads were aligned to the mouse reference genome(GRCm38.p6) with Hisat2 v2.0.5, and the aligned reads were used to quantify mRNA expression by using featureCounts v1.5.0-p3. Conclusion: Our study represents the first detailed analysis of islet transcriptomes from Mettl3flox/flox and β-Mettl3-KO mice, generated by RNA-seq technology. The RNA-seq analysis showed that 2560 genes were downregulated and 3408 genes were upregulated in the pancreatic islets of β-Mettl3-KO mice. GO analysis showed that the downregulated genes were primarily related to insulin secretion, SNARE binding, and mitochondrial respiratory chain, whereas the upregulated genes were associated with the immune response, B cell activation, and antigen binding. mRNA profiles in pancreatic islets of Mettl3flox/flox and β-Mettl3-KO mice were generated by deep sequencing using Illumina Novaseq 6000 platform (n=3 for each group).