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Production, Crystallization, and Structure Determination of the IKK-binding Domain of NEMO
Published on: December 28, 2019
Crystal structure of human micro-crystallin complexed with NADPH
Zhongjun Cheng1, Lihua Sun, Jianhua He
1National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, People's Republic of China.
Protein Science : a Publication of the Protein Society
|January 24, 2007
Summary
Researchers determined the crystal structure of human CRYM, a protein crucial for thyroid hormone transport and gene regulation. This structural insight reveals its NADPH-binding and dimerization domains, aiding in understanding its function.
Area of Science:
- Structural Biology
- Molecular Biology
- Biochemistry
Background:
- Human cytosolic 3,5,3'-triiodo-L-thyronine-binding protein (CRYM) is vital for thyroid hormone (T3) transport into nuclei.
- CRYM regulates thyroid-hormone-related gene expression.
- While homologs' structures exist, human CRYM's structure remained uncharacterized.
Purpose of the Study:
- To determine the crystal structure of human CRYM bound with NADPH.
- To provide structural insights into CRYM's function in thyroid hormone regulation.
- To compare human CRYM with its structural homologs.
Main Methods:
- X-ray crystallography was used to determine the human CRYM-NADPH complex structure.
- The structure was refined to 2.6 Å resolution.
- Comparative structural analysis was performed with known homologs.
Main Results:
- The crystal structure of human CRYM bound to NADPH was determined, revealing a dimer in the asymmetric unit.
- The structure comprises a Rossmann fold-like NADPH-binding domain and a dimerization domain.
- Conformational differences in the Arg83-His92 loop and varying peptide bond configurations (trans/cis) were observed between monomers.
Conclusions:
- The determined structure provides the first atomic-level view of human CRYM.
- Structural comparisons suggest a putative T3-binding site within human CRYM.
- This structural information is crucial for understanding CRYM's physiological roles in thyroid hormone transport and gene regulation.
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