A CRISPR screen in intestinal epithelial cells identifies novel factors for polarity and apical transport

Elife. 2023 Jan 20:12:e80135. doi: 10.7554/eLife.80135.


Epithelial polarization and polarized cargo transport are highly coordinated and interdependent processes. In our search for novel regulators of epithelial polarization and protein secretion, we used a genome-wide CRISPR/Cas9 screen and combined it with an assay based on fluorescence-activated cell sorting (FACS) to measure the secretion of the apical brush-border hydrolase dipeptidyl peptidase 4 (DPP4). In this way, we performed the first CRISPR screen to date in human polarized epithelial cells. Using high-resolution microscopy, we detected polarization defects and mislocalization of DPP4 to late endosomes/lysosomes after knockout of TM9SF4, anoctamin 8, and ARHGAP33, confirming the identification of novel factors for epithelial polarization and apical cargo secretion. Thus, we provide a powerful tool suitable for studying polarization and cargo secretion in epithelial cells. In addition, we provide a dataset that serves as a resource for the study of novel mechanisms for epithelial polarization and polarized transport and facilitates the investigation of novel congenital diseases associated with these processes.

Keywords: CRISPR; cell biology; electron microscopy; epithelial polarity; human; loss-of-function screen; membrane transport; microvillus inclusion disease.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Polarity
  • Dipeptidyl Peptidase 4* / metabolism
  • Epithelial Cells* / metabolism
  • Humans
  • Intestines
  • Membrane Proteins / metabolism
  • Microvilli / metabolism
  • Protein Transport


  • Dipeptidyl Peptidase 4
  • TM9SF4 protein, human
  • Membrane Proteins

Associated data

  • Dryad/10.5061/dryad.m0cfxpp62