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Updated: Jul 6, 2026
10:49
Pre-clinical Evaluation of Tyrosine Kinase Inhibitors for Treatment of Acute Leukemia
Published on: September 19, 2013
The crystal structure and biological function of leukemia inhibitory factor: implications for receptor binding
R C Robinson1, L M Grey, D Staunton
1Department of Biochemistry, University of Oxford, England.
Cell
|July 1, 1994
Summary
Researchers determined the structure of leukemia inhibitory factor (LIF) using X-ray crystallography. This reveals key regions involved in its interaction with receptors, offering insights into cytokine function.
Area of Science:
- Structural biology
- Biochemistry
- Molecular biology
Background:
- Leukemia inhibitory factor (LIF) is a crucial cytokine in the hematopoietic system.
- Cytokine structures often share common folding patterns, like the four alpha-helix bundle.
- Understanding LIF's structure is key to deciphering its biological roles.
Purpose of the Study:
- To determine the high-resolution three-dimensional structure of murine leukemia inhibitory factor (LIF).
- To compare LIF's structure with related cytokines and identify conserved features.
- To map functional regions involved in LIF's receptor interactions.
Main Methods:
- X-ray crystallography at 2.0 A resolution.
- Structural homology analysis with related hematopoietic cytokines.
- Sequence alignment and mapping onto the LIF structure.
- Analysis of human-mouse LIF chimeras for biological function and receptor specificity.
Main Results:
- The murine LIF structure adopts a four alpha-helix bundle fold, common in hematopoietic cytokines.
- LIF shares closest structural homology with granulocyte colony-stimulating factor and growth hormone (GH).
- Conserved surface regions were identified by mapping oncostatin M and ciliary neurotrophic factor sequences onto the LIF structure.
- Two specific regions in the fourth helix and preceding loop were implicated in LIF's receptor interaction.
Conclusions:
- The determined LIF structure provides a detailed molecular basis for its function.
- Structural similarities suggest a common evolutionary origin and mechanism of action for related cytokines.
- The identified receptor interaction regions are critical for understanding LIF's biological activity and specificity.
- A novel model for GH receptor binding may be required, incorporating features specific to LIF interactions.
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