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Updated: Aug 14, 2026

Fluorescence Biomembrane Force Probe: Concurrent Quantitation of Receptor-ligand Kinetics and Binding-induced Intracellular Signaling on a Single Cell
14:09

Fluorescence Biomembrane Force Probe: Concurrent Quantitation of Receptor-ligand Kinetics and Binding-induced Intracellular Signaling on a Single Cell

Published on: August 4, 2015

Fiz1, a novel zinc finger protein interacting with the receptor tyrosine kinase Flt3

I Wolf1, L R Rohrschneider

  • 1Fred Hutchinson Cancer Research Center, Division of Basic Sciences, Seattle, Washington 98109-1024, USA. iwolf@fhcrc.org

The Journal of Biological Chemistry
|July 20, 1999
PubMed

Insights

Researchers discovered Fiz1, a novel protein interacting with Flt3 receptor tyrosine kinase. This interaction, crucial for hematopoietic cell development, bypasses typical signaling pathways, offering new insights into cellular regulation.

Area of Science:

  • Molecular Biology
  • Cell Signaling
  • Hematopoiesis

Background:

  • Flt3 receptor tyrosine kinase is vital for hematopoietic progenitor cell proliferation, survival, and B lymphoid differentiation.
  • Signaling pathways governing Flt3-mediated growth and differentiation remain incompletely understood.

Purpose of the Study:

  • To identify novel signaling molecules that interact with the cytoplasmic domain of Flt3.
  • To characterize the interaction between Flt3 and newly identified binding partners.

Main Methods:

  • Yeast two-hybrid screening was employed to identify Flt3-interacting proteins.
  • In vitro and in vivo coprecipitation assays were used to confirm interactions.
  • Fiz1 mRNA expression and protein localization were analyzed.

Main Results:

  • A novel Flt3-interacting zinc finger protein (Fiz1) was identified, possessing 11 C(2)H(2)-type zinc fingers.
  • Fiz1 specifically binds to the catalytic domain of Flt3, independent of kinase activity, and not to related receptor tyrosine kinases.
  • Fiz1 is expressed ubiquitously in murine tissues and localizes to both nucleus and cytoplasm.

Conclusions:

  • A novel class of interaction between a receptor tyrosine kinase (Flt3) and a signaling molecule (Fiz1) was discovered.
  • This interaction is independent of the canonical SH2 domain/phosphotyrosine binding mechanism.
  • Fiz1 represents a new player in Flt3 signaling pathways relevant to hematopoiesis.

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