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A Modified Yeast-one Hybrid System for Heteromeric Protein Complex-DNA Interaction Studies
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Tunable Heteroassembly of a Plant Pseudoenzyme-Enzyme Complex
Irina V Novikova1, Mowei Zhou1, Chen Du2,3
1Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99354, United States.
ACS Chemical Biology
|September 14, 2021
Summary
Pseudoenzymes regulate biological processes. This study reveals how plant pseudoenzyme PDX1.2 forms tunable complexes with its enzyme homologue PDX1.3, providing a new interaction model.
Area of Science:
- Biochemistry
- Structural Biology
- Plant Science
Background:
- Pseudoenzymes are catalytically inactive proteins regulating biological functions.
- Understanding factors differentiating active enzymes from inactive pseudoenzymes is crucial.
- Plant pseudoenzyme PDX1.2 regulates vitamin B6 production via interaction with active homologues like PDX1.3.
Purpose of the Study:
- To elucidate the assembly mechanism of pseudoenzyme-enzyme pairs.
- To determine the structural basis of PDX1.2 and PDX1.3 interactions.
- To investigate the stoichiometry and arrangement of monomers within heterocomplexes.
Main Methods:
- Integrative experimental approach.
- Atomic structure determination of PDX1.2 and PDX1.3 heterocomplexes.
- Stoichiometry and arrangement analysis of monomers in heterocomplexes.
Main Results:
- Pseudoenzyme-enzyme associations form heterocomplexes with variable and tunable stoichiometry.
- Atomic structures of PDX1.2 and PDX1.3 heterocomplexes were determined.
- Symmetry-imposed preferences in PDX1.2-PDX1.3 interactions were identified within hetero-dodecamers.
Conclusions:
- A novel model for pseudoenzyme-enzyme interactions and their inherent heterogeneity is proposed.
- The findings offer insights into the regulation of vitamin B6 production in plants.
- The study highlights the importance of pseudoenzymes in biological regulation.
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