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Published on: July 17, 2019

Ras and phosphoinositide 3-kinase: partners in development and tumorigenesis

Antoine R Ramjaun1, Julian Downward

  • 1Signal Transduction Laboratory, Cancer Research UK London Research Institute, London, UK.

Cell Cycle (Georgetown, Tex.)
|November 13, 2007
PubMed

Insights

The Ras-phosphoinositide 3-kinase (PI 3-kinase) interaction is crucial for mammalian development and tumor formation. This study confirms its in vivo functionality, despite other identified signaling pathways.

Area of Science:

  • Cellular signaling pathways
  • Molecular biology
  • Cancer research

Background:

  • Receptor tyrosine kinase (RTK) signaling is critical for cell physiology and its deregulation is linked to human tumors.
  • The interaction between Ras and phosphoinositide 3-kinase (PI 3-kinase) activates PI 3-kinase, a key component in RTK signaling.
  • Recent discoveries of alternative interactions have questioned the physiological relevance of the direct Ras-PI 3-kinase binding.

Purpose of the Study:

  • To investigate the in vivo physiological relevance of the Ras-PI 3-kinase interaction in mammalian development and tumorigenesis.
  • To address uncertainties regarding the role of this specific signaling mechanism within the broader context of RTK signaling.

Main Methods:

  • Utilized a mouse model engineered to disrupt the Ras-PI 3-kinase interaction.
  • Assessed the functional consequences of this disruption on mammalian development.
  • Evaluated the impact on Ras-induced tumorigenesis.

Main Results:

  • Confirmed that the Ras-PI 3-kinase interaction is highly functional in vivo.
  • Demonstrated the interaction's critical role during mammalian development.
  • Established the interaction's importance in Ras-induced tumorigenesis.

Conclusions:

  • The direct Ras-PI 3-kinase interaction plays a significant functional role in vivo.
  • This interaction is essential for both normal mammalian development and the development of Ras-driven cancers.
  • Further research is needed to fully elucidate the complexities and future directions of this signaling pathway.

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