Single-cell transcriptomes of mouse bladder urothelium uncover novel cell type markers and urothelial differentiation characteristics

Cell Prolif. 2021 Apr;54(4):e13007. doi: 10.1111/cpr.13007. Epub 2021 Feb 3.

Abstract

Objectives: Much of the information to date in terms of subtypes and function of bladder urothelial cells were derived from anatomical location or by the expression of a small number of marker genes. To have a comprehensive map of the cellular anatomy of bladder urothelial cells, we performed single-cell RNA sequencing to thoroughly characterize mouse bladder urothelium.

Materials and methods: A total of 18,917 single cells from mouse bladder urothelium were analysed by unbiased single-cell RNA sequencing. The expression of the novel cell marker was confirmed by immunofluorescence using urinary tract infection models.

Results: Unsupervised clustering analysis identified 8 transcriptionally distinct cell subpopulations from mouse bladder urothelial cells. We discovered a novel type of bladder urothelial cells marked by Plxna4 that may be involved with host response and wound healing. We also found a group of basal-like cells labelled by ASPM that could be the progenitor cells of adult bladder urothelium. ASPM+ urothelial cells are significantly increased after injury by UPEC. In addition, specific transcription factors were found to be associated with urothelial cell differentiation. At the last, a number of interstitial cystitis/bladder pain syndrome-regulating genes were found differentially expressed among different urothelial cell subpopulations.

Conclusions: Our study provides a comprehensive characterization of bladder urothelial cells, which is fundamental to understanding the biology of bladder urothelium and associated bladder disease.

Keywords: bladder urothelium; cell subtype; single-cell transcriptome.

MeSH terms

  • Animals
  • Biomarkers / metabolism*
  • Calmodulin-Binding Proteins / genetics
  • Calmodulin-Binding Proteins / metabolism
  • Cell Differentiation
  • Cell Lineage
  • Disease Models, Animal
  • Female
  • Mice
  • Mice, Inbred C57BL
  • Nerve Tissue Proteins / genetics
  • Nerve Tissue Proteins / metabolism
  • Receptors, Cell Surface / genetics
  • Receptors, Cell Surface / metabolism
  • Sequence Analysis, RNA
  • Single-Cell Analysis
  • Stem Cells / cytology
  • Stem Cells / metabolism
  • Transcription Factors / genetics
  • Transcription Factors / metabolism
  • Transcriptome*
  • Urinary Bladder / cytology
  • Urinary Tract Infections / metabolism
  • Urinary Tract Infections / pathology
  • Urothelium / cytology
  • Urothelium / metabolism*

Substances

  • ASPM protein, mouse
  • Biomarkers
  • Calmodulin-Binding Proteins
  • Nerve Tissue Proteins
  • Plxna4 protein, mouse
  • Receptors, Cell Surface
  • Transcription Factors