1
|
Metzner FJ, Huber E, Hopfner KP, Lammens K. Structural and biochemical characterization of human Schlafen 5. Nucleic Acids Res 2022; 50:1147-1161. [PMID: 35037067 PMCID: PMC8789055 DOI: 10.1093/nar/gkab1278] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 12/08/2021] [Accepted: 12/14/2021] [Indexed: 11/15/2022] Open
Abstract
The Schlafen family belongs to the interferon-stimulated genes and its members are involved in cell cycle regulation, T cell quiescence, inhibition of viral replication, DNA-repair and tRNA processing. Here, we present the cryo-EM structure of full-length human Schlafen 5 (SLFN5) and the high-resolution crystal structure of the highly conserved N-terminal core domain. We show that the core domain does not resemble an ATPase-like fold and neither binds nor hydrolyzes ATP. SLFN5 binds tRNA as well as single- and double-stranded DNA, suggesting a potential role in transcriptional regulation. Unlike rat Slfn13 or human SLFN11, human SLFN5 did not cleave tRNA. Based on the structure, we identified two residues in proximity to the zinc finger motif that decreased DNA binding when mutated. These results indicate that Schlafen proteins have divergent enzymatic functions and provide a structural platform for future biochemical and genetic studies.
Collapse
Affiliation(s)
- Felix J Metzner
- Department of Biochemistry, Gene Center, Feodor-Lynen-Straße 25, 81377 München, Germany
| | - Elisabeth Huber
- Department of Biochemistry, Gene Center, Feodor-Lynen-Straße 25, 81377 München, Germany
| | - Karl-Peter Hopfner
- Department of Biochemistry, Gene Center, Feodor-Lynen-Straße 25, 81377 München, Germany
| | - Katja Lammens
- Department of Biochemistry, Gene Center, Feodor-Lynen-Straße 25, 81377 München, Germany
| |
Collapse
|
2
|
Schlafens: Emerging Proteins in Cancer Cell Biology. Cells 2021; 10:cells10092238. [PMID: 34571887 PMCID: PMC8465726 DOI: 10.3390/cells10092238] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 08/23/2021] [Accepted: 08/25/2021] [Indexed: 12/29/2022] Open
Abstract
Schlafens (SLFN) are a family of genes widely expressed in mammals, including humans and rodents. These intriguing proteins play different roles in regulating cell proliferation, cell differentiation, immune cell growth and maturation, and inhibiting viral replication. The emerging evidence is implicating Schlafens in cancer biology and chemosensitivity. Although Schlafens share common domains and a high degree of homology, different Schlafens act differently. In particular, they show specific and occasionally opposing effects in some cancer types. This review will briefly summarize the history, structure, and non-malignant biological functions of Schlafens. The roles of human and mouse Schlafens in different cancer types will then be outlined. Finally, we will discuss the implication of Schlafens in the anti-tumor effect of interferons and the use of Schlafens as predictors of chemosensitivity.
Collapse
|
3
|
Wang J, Huang Y, Huang L, Shi K, Wang J, Zhu C, Li L, Zhang L, Feng G, Liu L, Song Y. Novel biomarkers of intervertebral disc cells and evidence of stem cells in the intervertebral disc. Osteoarthritis Cartilage 2021; 29:389-401. [PMID: 33338640 DOI: 10.1016/j.joca.2020.12.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Revised: 10/23/2020] [Accepted: 12/09/2020] [Indexed: 02/08/2023]
Abstract
OBJECTIVE Rat intervertebral disc (IVD) is one of the most commonly used and cost-effective alternative models for human IVD. Many IVD related clinical studies need to be pre-tested on rat IVDs. However, studies on the heterogeneous cell clusters of the rat IVD are inadequate, and a further understanding of the marker genes and cell phenotypes of healthy mature IVD cells is essential. METHODS In this study, we used the 10X Genomics technology to analyze the single-cell transcriptome of purified wild-type rat IVDs. RESULTS We identified potentially new gene markers of IVDs via single-cell sequencing. Based on the unsupervised cluster analysis of 13,578 single-cell transcripts, 3 known IVD cell types were identified. We provided a complete single-cell gene expression map of the IVD. Immunohistochemical and immunofluorescence images of rat disc sections confirmed the new marker genes of all cell types. One group of heterologous cell groups expressed multi-functional stem cell (MSC)-specific genes, indicating the stem cell potential of IVD cells. CONCLUSION We provided the phenotype and marker genes of IVD cells at the single-cell level, reconfirmed existing data, and proposed new marker genes, including MSC marker genes. By identifying more accurate target cells and genes, our results pave the way for further study of the response of individual disc cells to disease states and provide the basis for future disc regeneration therapies.
Collapse
Affiliation(s)
- J Wang
- Department of Orthopedic Surgery and Orthopedic Research Institute, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China.
| | - Y Huang
- Department of Orthopedic Surgery and Orthopedic Research Institute, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China.
| | - L Huang
- Department of Orthopedic Surgery and Orthopedic Research Institute, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China.
| | - K Shi
- Department of Orthopedic Surgery and Orthopedic Research Institute, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China.
| | - J Wang
- Department of Orthopedic Surgery and Orthopedic Research Institute, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China.
| | - C Zhu
- Department of Orthopedic Surgery and Orthopedic Research Institute, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China.
| | - L Li
- Department of Science and Technology, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China.
| | - L Zhang
- Analytical and Testing Center, State Key Laboratory of Oral Diseases, School of Materials Science and Engineering, Sichuan University, Chengdu, 610065, China.
| | - G Feng
- Department of Orthopedic Surgery and Orthopedic Research Institute, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China.
| | - L Liu
- Department of Orthopedic Surgery and Orthopedic Research Institute, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China.
| | - Y Song
- Department of Orthopedic Surgery and Orthopedic Research Institute, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China.
| |
Collapse
|
4
|
Slfn2 Regulates Type I Interferon Responses by Modulating the NF-κB Pathway. Mol Cell Biol 2018; 38:MCB.00053-18. [PMID: 29866656 DOI: 10.1128/mcb.00053-18] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 05/23/2018] [Indexed: 11/20/2022] Open
Abstract
Although members of the Slfn family have been implicated in the regulation of type I interferon (IFN) responses, the mechanisms by which they mediate their effects remain unknown. In the present study, we provide evidence that targeted disruption of the Slfn2 gene leads to increased transcription of IFN-stimulated genes (ISGs) and enhanced type I IFN-mediated antiviral responses. We demonstrate that Slfn2 interacts with protein phosphatase 6 regulatory subunit 1 (PPP6R1), leading to reduced type I IFN-induced activation of nuclear factor kappa B (NF-κB) signaling, resulting in reduced expression of ISGs. Altogether, these data suggest a novel mechanism by which Slfn2 controls ISG expression and provide evidence for a critical role for Slfn2 in the regulation of IFN-mediated biological responses.
Collapse
|