Integrated screens uncover a cell surface tumor suppressor gene KIRREL involved in Hippo pathway

Chao Wang1, Xu Feng1, Dan Su1

  • 1Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX.

Insights

Loss of cell surface protein Kirre1 (KIRREL) promotes tumor growth by inactivating the Hippo pathway. This study reveals KIRREL as a novel tumor suppressor and highlights CRISPR screening for cell surface protein discovery.

Area of Science:

  • Oncology
  • Cell Biology
  • Molecular Biology

Background:

  • Cell surface proteins are crucial for biological processes and cancer development.
  • They are valuable markers for cell identity and drug targets.
  • Comprehensive functional analysis of cell surface proteins is limited.

Purpose of the Study:

  • To functionally analyze cell surface proteins using in vivo CRISPR screens.
  • To identify cell surface proteins affecting tumor survival and proliferation.
  • To uncover novel cell surface tumor suppressors and their mechanisms.

Main Methods:

  • Designed a de novo library targeting cell surface proteins.
  • Performed in vivo CRISPR screens to assess protein function in tumors.
  • Utilized a Hippo pathway reporter for enrichment screening.
  • Conducted biochemical assays to determine protein interactions.

Main Results:

  • Loss of Kirre1 (KIRREL) significantly promoted tumor growth in vivo.
  • KIRREL was identified through CRISPR screens targeting the Hippo pathway.
  • KIRREL directly binds to SAV1, activating the Hippo tumor suppressor pathway.

Conclusions:

  • Kirre1 acts as a cell surface tumor suppressor.
  • KIRREL regulates tumor growth via the Hippo pathway.
  • CRISPR screening is a powerful approach for cell surface protein discovery in cancer research.

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