Poster Presentation GENEMAPPERS 2024

Analysis of gene expression impacts of valproate on a human induced pluripotent stem cell line using long read RNA-Sequencing (#55)

Isabel Ayora 1 , Oscar Graham 1 , Allison Miller 1 , Stephanie Bozonet 1 , Shaya Helem 1 , Martin Kennedy 1
  1. University of Otago, Christchurch Central, SOUTH ISLAND, New Zealand

Valproate (VPA) is a widely used drug. Currently, the primary clinical indications of VPA are bipolar disorder, epilepsy, and migraine headaches (1). VPA is also a potent teratogen (2, 3). Despite over half a century of clinical use, the properties of VPA are still being characterised (3, 4). One established VPA mechanism is direct inhibition of histone deacetylases, resulting in histone hyperacetylation and demethylation of nuclear and mitochondrial DNA (3, 5, 6). These epigenetic modifications have been found to alter transcription across the genome, which may underly both therapeutic and teratogenic effects of VPA (3, 5-7). To explore these transcriptional impacts, we are investigating dose-dependent effects of VPA exposure in undifferentiated KOLF2.1J, a well-characterised human induced pluripotent stem cell line (8). Human induced pluripotent stem cells have not previously been used to test VPA effects. Undifferentiated KOLF2.1J cells will provide a benchmark for VPA-induced gene expression changes, potentially preceding future work in KOLF2.1J cells differentiated along cellular lineages relevant to clinical indications of this drug. VPA-exposed pluripotent cells may also model the drug’s teratogenicity on the level of transcription. The total RNA isolated from the VPA-exposed KOLF2.1J cells will be converted to cDNA for long-read nanopore sequencing, allowing exploration of differential expression and differential isoform usage in whole transcripts. An established bioinformatics pipeline will be used to quantify these transcriptional changes. Our hypothesis is that transcriptional changes in VPA-exposed KOLF2.1J cells will illuminate genomic regions involved in the therapeutic effects of VPA, which may be candidate regions of pathological or aetiological relevance.

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