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Mapping Critical Residues in ATG11's Coiled-Coil 2 Domain that Block Multiple Interactions and Disrupt Selective
Mitchell D Meyer1, Jasmine Winzeler1, Sophia M Taylor1
1Department of Chemistry, Eastern Michigan University, Ypsilanti, MI, United States.
Frontiers in Cell and Developmental Biology
|February 4, 2022
Summary
Researchers identified critical residues in the Atg11 protein essential for selective autophagy initiation in yeast. Mutating these residues disrupts protein interactions and blocks the autophagosome formation process.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Selective autophagy maintains cellular health by degrading damaged components.
- Atg11 is a crucial adapter protein initiating selective autophagy in yeast (S. Cerevisiae).
- Atg11's structure includes coiled-coil domains and disordered regions, facilitating dimerization and interactions with key autophagosome machinery like Atg1 and Atg9.
Purpose of the Study:
- To systematically map residues within the coiled-coil 2 domain of Atg11 essential for its structure and function.
- To identify specific amino acids critical for Atg11 dimerization and its interactions with Atg1 and Atg9.
Main Methods:
- Systematic directed mutagenesis of the Atg11 coiled-coil 2 domain.
- Yeast-2-hybrid assays to assess protein-protein interactions.
- Coimmunoprecipitation to confirm interactions in vivo.
Main Results:
- Three residues (I562, Y565, I569) in the Atg11 coiled-coil 2 domain were found to be critical for function.
- Mutation of these residues, particularly Y565, impaired Atg11 dimerization.
- The identified mutations disrupted the interaction between Atg11 and its partners, Atg1 and Atg9.
Conclusions:
- Specific residues within the Atg11 coiled-coil 2 domain are indispensable for its structural integrity and function in selective autophagy.
- The identified critical residues are essential for Atg11 dimerization and its ability to recruit Atg1 and Atg9, thereby regulating autophagosome formation.
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