Related Experiment Videos
Human interleukin-3 contains a discontinuous zinc binding domain
V Smit1, P A van Veelen, U R Tjaden
1TNO Institute of Applied Radiobiology and Immunology, Rijswijk, The Netherlands.
Biochemical and Biophysical Research Communications
|September 16, 1992
Summary
Human interleukin-3 (hIL-3) is a zinc-binding protein, with binding primarily determined by two specific amino acid sequences. This zinc binding may influence the phosphorylation of its receptor.
Area of Science:
- Biochemistry
- Molecular Biology
- Immunology
Background:
- Human interleukin-3 (hIL-3) possesses consensus sequences characteristic of zinc-binding proteins.
- The role of zinc in hIL-3 structure and function was previously uncharacterized.
Purpose of the Study:
- To investigate the hypothesis that hIL-3 specifically binds zinc.
- To identify the amino acid sequences responsible for zinc binding.
- To explore the potential functional implications of hIL-3 zinc binding.
Main Methods:
- Protein dot blotting with radioactive zinc.
- Metal ion competition assays.
- Protease treatment and plasma desorption mass spectrometry for domain localization.
Main Results:
- Specific zinc binding of hIL-3 was demonstrated.
- Zinc binding was confirmed to be metal-specific.
- The primary zinc-binding domains were localized to two distinct amino acid stretches (Threonine 11-Lysine 28 and Asparagine 80-Lysine 100).
Conclusions:
- Human interleukin-3 is definitively identified as a zinc-binding protein.
- The identified consensus sequences are crucial for hIL-3's zinc-binding capacity.
- Zinc binding of hIL-3 is proposed to be involved in the (de)phosphorylation of the hIL-3 receptor.