Cbl and Cbl-b ubiquitin ligases are essential for intestinal epithelial stem cell maintenance
Neha Zutshi,
Bhopal C. Mohapatra,
Pinaki Mondal,
Wei An,
Benjamin T. Goetz,
Shuo Wang,
Sicong Li,
Matthew D. Storck,
David F. Mercer,
Adrian R. Black,
Sarah P. Thayer,
Jennifer D. Black,
Chi Lin,
Vimla Band,
Hamid Band
Affiliations
Neha Zutshi
Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA; Department of Pathology & Microbiology, University of Nebraska Medical Center, Omaha, NE 68198, USA
Bhopal C. Mohapatra
Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA; Department of Genetics, Cell Biology & Anatomy, University of Nebraska Medical Center, Omaha, NE 68198, USA
Pinaki Mondal
Department of Surgery, University of Nebraska Medical Center, Omaha, NE 68198, USA
Wei An
Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA
Benjamin T. Goetz
Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA
Shuo Wang
Department of Radiation Oncology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
Sicong Li
Department of Radiation Oncology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
Matthew D. Storck
Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA
David F. Mercer
Department of Surgery, University of Nebraska Medical Center, Omaha, NE 68198, USA
Adrian R. Black
Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA; Fred & Pamela Buffet Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198, USA
Sarah P. Thayer
Department of Surgery, University of Nebraska Medical Center, Omaha, NE 68198, USA; Fred & Pamela Buffet Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198, USA
Jennifer D. Black
Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA; Fred & Pamela Buffet Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198, USA
Chi Lin
Department of Radiation Oncology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA; Fred & Pamela Buffet Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198, USA
Vimla Band
Department of Genetics, Cell Biology & Anatomy, University of Nebraska Medical Center, Omaha, NE 68198, USA; Fred & Pamela Buffet Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198, USA; Corresponding author
Hamid Band
Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA; Department of Pathology & Microbiology, University of Nebraska Medical Center, Omaha, NE 68198, USA; Department of Genetics, Cell Biology & Anatomy, University of Nebraska Medical Center, Omaha, NE 68198, USA; Fred & Pamela Buffet Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198, USA; Corresponding author
Summary: Receptor tyrosine kinases (RTKs) control stem cell maintenance vs. differentiation decisions. Casitas B-lineage lymphoma (CBL) family ubiquitin ligases are negative regulators of RTKs, but their stem cell regulatory roles remain unclear. Here, we show that Lgr5+ intestinal stem cell (ISC)-specific inducible Cbl-knockout (KO) on a Cblb null mouse background (iDKO) induced rapid loss of the Lgr5Hi ISCs with transient expansion of the Lgr5Lo transit-amplifying population. LacZ-based lineage tracing revealed increased ISC commitment toward enterocyte and goblet cell fate at the expense of Paneth cells. Functionally, Cbl/Cblb iDKO impaired the recovery from radiation-induced intestinal epithelial injury. In vitro, Cbl/Cblb iDKO led to inability to maintain intestinal organoids. Single-cell RNA sequencing in organoids identified Akt-mTOR (mammalian target of rapamycin) pathway hyperactivation upon iDKO, and pharmacological Akt-mTOR axis inhibition rescued the iDKO defects. Our results demonstrate a requirement for Cbl/Cblb in the maintenance of ISCs by fine-tuning the Akt-mTOR axis to balance stem cell maintenance vs. commitment to differentiation.
