190 | Preprocessing of snRNAseq data from striata in the 6-OHDA mouse model of Parkinson’s disease and levodopa induced dyskinesia: From raw data to annotated clusters.

Disorders of the Nervous System

Author: Bárbara Fátima Martínez Marques | Email: barbarafmartinezm@gmail.com

Bárbara Martínez , Chang Li , Yogita Sharma , Jenny Johansson , Anna Hammarberg , Claudio Schuster , Marcelo Marti , Juan Ferrario , Angela Cenci , Melina Bordone

1° Laboratorio de Neurobiología de la Enfermedad del Parkinson, IB3, UBA-CONICET
2° Lund University

The striatum is a complex brain region essential for motor function and implicated in levodopa (L-DOPA)-induced dyskinesia (LID), the main side effect of Parkinson’s disease (PD) treatment. The aim was to perform single nuclei RNAsequencing (snRNAseq) from striata of intact and hemiparkinsonian mice with or without LID to obtain cell-type specific transcriptional profiles. For this, hemiparkinsonism was induced with an unilateral injection of 6-OHDA in the mid forebrain bundle and 3 weeks later, dyskinesia was induced by L-DOPA for one week. Twenty hours after the last injection, striata were immediately dissected for nuclei isolation. cDNA libraries were prepared and sequenced from 8500 FACS-sorted nuclei from 4 samples/group using a droplet-based RNA sequencing technology (10X Genomics). Data were first preprocessed to generate high quality expression matrices from each sample and then integrated into a single one containing 46973 nuclei that were clustered and annotated based on the expression of unique and well-established mRNA markers. This approach allowed us to identify dSPN, iSPN, eSPN interneurons, microglia, astrocytes, mature oligodendrocytes, oligodendrocyte precursor cells and pericytes, and most of them were equally represented among treatments. This is the first transcriptomic study that has been done on LID at the single cell level. In the future, we will address the transcriptional changes undergoing the different striatal population upon PD and LID.