Poster abstracts
Poster number 129 submitted by Sophia Dorsey
Exploring the role of alternative polyadenylation on elavl1a expression and function during zebrafish erythropoiesis
Sophia Dorsey (Biology, Oberlin College), Sandra Baltazar (Biology, Oberlin College), Emma Wei (Biology, Oberlin College), Monica Blatnik (Biology, Oberlin College)
Abstract:
Addition of the poly(A) tail occurs during the final steps of transcription and mRNA processing, which is crucial for the export, stability, and translation of a mature mRNA. For many genes, the addition of the poly(A) tail can occur at one of multiple locations within the 3'UTR. This process, known as alternative polyadenylation (APA), results in the production of mRNAs with different 3'UTR lengths that can include or exclude (depending on the APA site used) important binding sites for post-transcriptional regulatory factors. Consequently, this can alter the stability, localization, and/or translation of the mRNA. During development, APA can affect cellular identity and function, where 3’UTR lengthening can impose more “fine-tuned” regulation of genes involved in cell fate determination (1). Our lab uses zebrafish as a model to study the developmental effects of APA on the RNA-binding protein Elavl1a. This protein has been shown to bind and stabilize gata1a, a transcription factor essential for the proliferation of erythrocytes in zebrafish. However, the post-transcriptional regulation of elavl1a and its effects on erythropoiesis, are not well understood. Consistent with previous studies using poly(A)-position profiling by sequencing (3P-seq) on zebrafish embryos at different developmental timepoints (2), we have found that elavl1a 3’UTR length increases during organogenesis, between 24 hours post fertilization (hpf) to 48 hpf. This suggests that elavl1a transcripts may be subject to differential post-transcriptional regulation during the time that mature erythrocytes are entering circulation. Preliminary fluorescent in situ hybridization data shows the 2.2kb elavl1a isoform expression is increased at 48hpf, compared to 24hpf, in areas where red blood cell differentiation occurs. Our future work aims to investigate the role of APA on post-transcriptional regulation of elavl1a during embryonic development and cell fate determination.
References:
1) Lorenzo Gallicchio, Gonzalo H. Olivares, Cameron W. Berry & Margaret
T. Fuller (2023) Regulation and function of alternative polyadenylation in development and
differentiation, RNA Biology, 20:1, 908-925, DOI: 10.1080/15476286.2023.2275109
2) Ulitsky, I., Shkumatava, A., Jan, C. H., Subtelny, A. O., Koppstein, D., Bell, G. W., ... & Bartel, D. P. (2012). Extensive alternative polyadenylation during zebrafish development. Genome research, 22(10), 2054-2066.
Keywords: Alternative Polyadenylation, Post-transcriptional , Development