Exploring mechanisms of nephron maturation using scRNAseq

Sarah Williams⁰, Rachel Lam⁰, Yasmin Neirijnck¹, Pauline Sararols¹, Chloé Mayère¹, Serge Nef¹, Alex Combes⁰
(0) Monash University
(1) University of Geneva

Find me on Tues Nov 24th, 1:40-3pm AEDT in Remo, table 73

Abstract
Three paired kidney structures arise sequentially during mammalian development: the pronephros, the mesonephros and the metanephros. Only the metanephric kidney is maintained into adulthood but each kidney structure contains immature nephrons - precursors of the filtration units that underwrite kidney function.

Stem cell models of the human brain recapitulate the timing and order of developmental processes, taking months to reach maximal size and maturity. In contrast, stem cell-derived kidney organoids form immature nephrons in 10-14 days, roughly half the time expected for metanephric nephrons. The timing and maturity of nephron formation in kidney organoids raises the possibility that current protocols may generate tissue closer to pronephric or mesonephric kidneys. However, it is unclear whether there are molecular differences between early nephrons in each context, and why only metanephric nephrons reach functional maturity.

In this work we compare single cell RNAseq data from the developing mouse mesonephric and metanephric kidney. Published and new datasets were combined with the Seurat integration method. Cluster labels were assigned via label transfer and identification of known markers. Differential expression was calculated between datasets and within individual cell types via a pseudobulk approach with limma. Initial results have recapitulated known expression patterns in these tissues, lending confidence to analyses of novel marker genes and cell communication driving nephron maturation. This work will facilitate further comparative analysis of embryonic kidney structures and kidney organoids. It may also lead to new approaches to drive nephron maturation, which are required to model disease states that manifest in adulthood