Analysis of alternative splicing and alternative polyadenylation of Nosema ceranae genes based on Nanopore full-length transcriptome dataset

• 1、College of Animal Sciences (College of Bee Science), Fujian Agriculture and Forestry University, Fuzhou 350002

Abstract：This work aims to analyze alternative splicing (AS) of genes and alternative polyadenylation (APA) of full-length transcripts on basis of our previously obtained Nosema ceranae full-length transcriptome data. Astalavista software was used to identify the type of AS of genes in N. ceranae. TAPIS pipeline was utilized to explore APA of N. ceranae full-length transcripts. MEME software was employed to investigate statistics of sequences at 50 bp upstream of poly (A) splicing sites as well as identify motifs. In this study, five AS events occurred in five genes were identified, including one alternative donor site (ADS) and four intron retention (IR). In addition, a total of 233 full-length transcripts with APA were identified, and among them those transcripts containing one poly (A) splicing site was the most abundant (143, 61.37%). Moreover, upstream and downstream sequences of 3\' UTR within N. ceranae full-length transcripts showed an obvious base bias, and U was enriched in the upstream of 3\' UTR, while A was enriched in the downstream of 3\' UTR. Besides, three motifs such as AAUAAA, UGAUGC and GCGACG were identified at the upstream of poly (A) splicing site. The results reveal the complexity of the transcriptome of N. ceranae, offer beneficial information for improvement of current annotations of N. ceranae genome and transcriptome, and provide a foundation for further study on the role of AS and APA in gene expression regulation of N. ceranae.

Keywords： third-generation sequencing technology full-length transcriptome Nosema ceranae alternative splicing alternative polyadenylation