Structural basis of dynamic P5CS filaments

Abstract
Data availability
Article and author information
Metrics

Abstract

The bifunctional enzyme Δ¹-pyrroline-5-carboxylate synthase (P5CS) is vital to the synthesis of proline and ornithine, playing an essential role in human health and agriculture. Pathogenic mutations in P5CS gene (ALDH18A1) lead to neurocutaneous syndrome and skin relaxation connective tissue disease in humans, and P5CS deficiency seriously damages the ability to resist adversity in plants. We have recently found that P5CS forms the cytoophidium in vivo and filaments in vitro. However, it is difficult to appreciate the function of P5CS filamentation without precise structures. Using cryo-electron microscopy, here we solve structures of Drosophila full-length P5CS in three states at resolution from 3.1 to 4.3 Å. We observe distinct ligand-binding states and conformational changes for the GK and GPR domains, respectively. Divergent helical filaments are assembled by P5CS tetramers and stabilized by multiple interfaces. Point mutations disturbing those interfaces prevent P5CS filamentation and greatly reduce the enzymatic activity. Our findings reveal that filamentation is crucial for the coordination between the GK and GPR domains, providing structural basis for catalytic function of P5CS filaments.

Data availability

7F5T 7F5U 7F5V 7F5X 7WX3 7WX4 7WXF 7WXG 7WXH 7WXIFigure 5-Source Data 1 in enzyme activity assay, which related to Figure 5D;Validation summary report as Related Manuscript File;Maps and coordinates data as a Supporting Zip Document.

Article and author information

Author details

Jiale Zhong

School of Life Science and Technology, ShanghaiTech University, Shanghai, China

Competing interests
The authors declare that no competing interests exist.

"This ORCID iD identifies the author of this article:" 0000-0001-5873-0450
Chen-Jun Guo

School of Life Science and Technology, ShanghaiTech University, Shanghai, China

Competing interests
The authors declare that no competing interests exist.
Xian Zhou

School of Life Science and Technology, ShanghaiTech University, Shanghai, China

Competing interests
The authors declare that no competing interests exist.
Chia-Chun Chang

School of Life Science and Technology, ShanghaiTech University, Shanghai, China

Competing interests
The authors declare that no competing interests exist.
Boqi Yin

School of Life Science and Technology, ShanghaiTech University, Shanghai, China

Competing interests
The authors declare that no competing interests exist.
Tianyi Zhang

School of Life Science and Technology, ShanghaiTech University, Shanghai, China

Competing interests
The authors declare that no competing interests exist.
Huanhuan Hu

School of Life Science and Technology, ShanghaiTech University, Shanghai, China

Competing interests
The authors declare that no competing interests exist.
Guang-Ming Lu

School of Life Science and Technology, ShanghaiTech University, Shanghai, China

Competing interests
The authors declare that no competing interests exist.
Ji-Long Liu

School of Life Science and Technology, ShanghaiTech University, Shanghai, China

For correspondence
Liujl3@shanghaitech.edu.cn

Competing interests
The authors declare that no competing interests exist.

"This ORCID iD identifies the author of this article:" 0000-0002-4834-8554

Funding

Ministry of Science and Technology of the People's Republic of China (2021YFA0804701-4)

Ji-Long Liu

National Natural Science Foundation of China (31771490)

Ji-Long Liu

Shanghai Science and Technology Commission (20JC1410500)

Ji-Long Liu

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Copyright

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.