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Updated: Jun 16, 2026

Monitoring Hippo Signaling Pathway Activity Using a Luciferase-based Large Tumor Suppressor (LATS) Biosensor
07:16

Monitoring Hippo Signaling Pathway Activity Using a Luciferase-based Large Tumor Suppressor (LATS) Biosensor

Published on: September 13, 2018

The WW domain protein Kibra acts upstream of Hippo in Drosophila

Roland Baumgartner1, Ingrid Poernbacher, Nathalie Buser

  • 1Institute of Molecular Systems Biology, ETH Zürich, Wolfgang-Pauli-Strasse 16, 8093 Zürich, Switzerland.

Developmental Cell
|February 18, 2010
PubMed

Insights

Kibra, a WW domain protein, acts upstream of the Hippo kinase pathway, regulating organ size control. It interacts with Merlin and synergizes with Expanded, primarily influencing the Merlin signaling branch.

Area of Science:

  • Cell biology
  • Molecular biology
  • Developmental biology

Background:

  • The Hippo kinase pathway is crucial for organ size control and tumor suppression.
  • It functions by regulating cell proliferation and apoptosis through a core kinase cascade.
  • Upstream regulators of Hippo signaling, particularly for the Merlin branch, are not well understood.

Purpose of the Study:

  • To identify novel components upstream of the Hippo kinase pathway.
  • To elucidate the regulatory mechanisms of the Merlin signaling branch.
  • To understand Kibra's role in Hippo pathway signaling.

Main Methods:

  • Investigated the function of the WW domain protein Kibra.
  • Analyzed Kibra's interaction with Merlin and Expanded.
  • Assessed Kibra's position within the Hippo signaling cascade.

Main Results:

  • Identified Kibra as a novel component of the Hippo signaling pathway.
  • Demonstrated that Kibra acts upstream of both Hippo and Merlin kinases.
  • Showed Kibra physically interacts with Merlin and acts synergistically with Expanded.
  • Kibra predominantly regulates the Merlin signaling branch.

Conclusions:

  • Kibra is a key upstream regulator in the Merlin-mediated branch of the Hippo pathway.
  • Understanding Kibra's function provides new insights into Hippo pathway regulation.
  • This finding contributes to the broader understanding of organ size control and tumorigenesis.

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