1
|
Li Y, Sun X, Yang L. Structure/epitope analysis and IgE binding activities of three cyclophilin family proteins from Dermatophagoides pteronyssinus. Sci Rep 2023; 13:13630. [PMID: 37604978 PMCID: PMC10442367 DOI: 10.1038/s41598-023-40720-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Accepted: 08/16/2023] [Indexed: 08/23/2023] Open
Abstract
Cyclophilins (CyPs) are involved in basic cellular functions and a wide variety of pathophysiological processes. Many CyPs have been identified as the aetiological agent and influence on the immune system. In the present study, the physicochemical and immunologic characteristics of three proteins of CyPs family (CyPA, CyPB and CyPE) were analyzed. The results indicated that CyPE showed a closer evolutionary relationship with allergenic CyPA. The structure and antigenicity of CyPE was significantly similar with CyPA. B-cell epitopes of CyPE and CyPA were predicted via multiple immunoinformatics tools. Three consensus B-cell epitopes of CyPE and CyPAs were finally determined. To verify results of in silico analysis, three proteins of CyPs family (CyPA, CyPE and CyPB) were cloned and expressed from Dermatophagoides pteronyssinus. ELISA results indicated that the positive reaction rates of the three proteins to patient serum are CyPA (21.4%), CyPE (7.1%), and CyPB (0%), illustrating that the IgE activity was exhibited in CypA and CypE excluding CyPB. Structure and immunoinformatics analysis demonstrated that the RNA-binding motif of CyPE could reduce the immunogenicity of PPIase domain of CyPE. The reason that CyPB has no IgE activity might be the structure mutation of CyPB on B-cell epitopes.
Collapse
Affiliation(s)
- Yuwei Li
- Department of Respiratory Medicine, The Seventh Affiliated Hospital of Southern Medical University, Foshan, 528244, Guangdong, China
- Department of Respirology and Allergy, The Third Affiliated Hospital of Shenzhen University, Shenzhen, 518020, China
- Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, Jilin, China
| | - Xizhuo Sun
- Department of Respirology and Allergy, The Third Affiliated Hospital of Shenzhen University, Shenzhen, 518020, China
| | - Liteng Yang
- Department of Respiratory Medicine, The Seventh Affiliated Hospital of Southern Medical University, Foshan, 528244, Guangdong, China.
- Department of Respirology and Allergy, The Third Affiliated Hospital of Shenzhen University, Shenzhen, 518020, China.
| |
Collapse
|
2
|
Acosta J, Li Q, Freeburg NF, Murali N, Indeglia A, Grothusen GP, Cicchini M, Mai H, Gladstein AC, Adler KM, Doerig KR, Li J, Ruiz-Torres M, Manning KL, Stanger BZ, Busino L, Murphy M, Wan L, Feldser DM. p53 restoration in small cell lung cancer identifies a latent cyclophilin-dependent necrosis mechanism. Nat Commun 2023; 14:4403. [PMID: 37479684 PMCID: PMC10362054 DOI: 10.1038/s41467-023-40161-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 07/12/2023] [Indexed: 07/23/2023] Open
Abstract
The p53 tumor suppressor regulates multiple context-dependent tumor suppressive programs. Although p53 is mutated in ~90% of small cell lung cancer (SCLC) tumors, how p53 mediates tumor suppression in this context is unknown. Here, using a mouse model of SCLC in which endogenous p53 expression can be conditionally and temporally regulated, we show that SCLC tumors maintain a requirement for p53 inactivation. However, we identify tumor subtype heterogeneity between SCLC tumors such that p53 reactivation induces senescence in a subset of tumors, while in others, p53 induces necrosis. We pinpoint cyclophilins as critical determinants of a p53-induced transcriptional program that is specific to SCLC tumors and cell lines poised to undergo p53-mediated necrosis. Importantly, inhibition of cyclophilin isomerase activity, or genetic ablation of specific cyclophilin genes, suppresses p53-mediated necrosis by limiting p53 transcriptional output without impacting p53 chromatin binding. Our study demonstrates that intertumoral heterogeneity in SCLC influences the biological response to p53 restoration, describes a cyclophilin-dependent mechanism of p53-regulated cell death, and uncovers putative mechanisms for the treatment of this most-recalcitrant tumor type.
Collapse
Affiliation(s)
- Jonuelle Acosta
- Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Cell and Molecular Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Qinglan Li
- Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Nelson F Freeburg
- Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Cell and Molecular Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Nivitha Murali
- Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Alexandra Indeglia
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Grant P Grothusen
- Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Cell and Molecular Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Michelle Cicchini
- Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Hung Mai
- Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Amy C Gladstein
- Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Cell and Molecular Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Keren M Adler
- Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Cell and Molecular Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Katherine R Doerig
- Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Cell and Molecular Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jinyang Li
- Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Miguel Ruiz-Torres
- Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Kimberly L Manning
- Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Ben Z Stanger
- Cell and Molecular Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, PA, USA
| | - Luca Busino
- Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Cell and Molecular Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, PA, USA
| | - Maureen Murphy
- Cell and Molecular Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Program in Molecular and Cellular Oncogenesis, The Wistar Institute, Philadelphia, PA, USA
| | - Liling Wan
- Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Cell and Molecular Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, PA, USA
| | - David M Feldser
- Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
- Cell and Molecular Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
- Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, PA, USA.
| |
Collapse
|
3
|
Blatter M, Meylan C, Cléry A, Giambruno R, Nikolaev Y, Heidecker M, Solanki JA, Diaz MO, Gabellini D, Allain FHT. RNA binding induces an allosteric switch in Cyp33 to repress MLL1-mediated transcription. SCIENCE ADVANCES 2023; 9:eadf5330. [PMID: 37075125 PMCID: PMC10115415 DOI: 10.1126/sciadv.adf5330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Mixed-lineage leukemia 1 (MLL1) is a transcription activator of the HOX family, which binds to specific epigenetic marks on histone H3 through its third plant homeodomain (PHD3) domain. Through an unknown mechanism, MLL1 activity is repressed by cyclophilin 33 (Cyp33), which binds to MLL1 PHD3. We determined solution structures of Cyp33 RNA recognition motif (RRM) free, bound to RNA, to MLL1 PHD3, and to both MLL1 and the histone H3 lysine N6-trimethylated. We found that a conserved α helix, amino-terminal to the RRM domain, adopts three different positions facilitating a cascade of binding events. These conformational changes are triggered by Cyp33 RNA binding and ultimately lead to MLL1 release from the histone mark. Together, our mechanistic findings rationalize how Cyp33 binding to MLL1 can switch chromatin to a transcriptional repressive state triggered by RNA binding as a negative feedback loop.
Collapse
Affiliation(s)
- Markus Blatter
- Department of Biology, Institute of Biochemistry, ETH Zurich, 8093 Zurich, Switzerland
- Corresponding author. (F.H.-T.A.); (M.B.)
| | - Charlotte Meylan
- Department of Biology, Institute of Biochemistry, ETH Zurich, 8093 Zurich, Switzerland
| | - Antoine Cléry
- Department of Biology, Institute of Biochemistry, ETH Zurich, 8093 Zurich, Switzerland
| | - Roberto Giambruno
- Gene Expression and Muscular Dystrophy Unit, Division of Genetics and Cell Biology, IRCCS San Raffaele Scientific Institute, Milan 20132, Italy
| | - Yaroslav Nikolaev
- Department of Biology, Institute of Biochemistry, ETH Zurich, 8093 Zurich, Switzerland
| | - Michel Heidecker
- Department of Biology, Institute of Biochemistry, ETH Zurich, 8093 Zurich, Switzerland
| | - Jessica Arvindbhai Solanki
- Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University of Chicago Medical Center, University of Chicago, Chicago, IL, USA
| | - Manuel O. Diaz
- Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University of Chicago Medical Center, University of Chicago, Chicago, IL, USA
| | - Davide Gabellini
- Gene Expression and Muscular Dystrophy Unit, Division of Genetics and Cell Biology, IRCCS San Raffaele Scientific Institute, Milan 20132, Italy
| | - Frédéric H.-T. Allain
- Department of Biology, Institute of Biochemistry, ETH Zurich, 8093 Zurich, Switzerland
- Corresponding author. (F.H.-T.A.); (M.B.)
| |
Collapse
|
4
|
Liu H, He H, Tian Y, Cui J, Wang S, Wang H. Cyclophilin A accelerates SiO 2-induced macrophage foaming. Cell Signal 2023; 103:110562. [PMID: 36535629 DOI: 10.1016/j.cellsig.2022.110562] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 12/06/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022]
Abstract
Silicosis is a common occupational disease characterized by lung inflammation, fibrosis and pulmonary dysfunction caused by long-term inhalation of free SiO2. Cell foaming and the change of CyPA have been observed in SiO2-induced macrophages, but the specific mechanism of CyPA in SiO2-induced foam cells remains poorly understood. The purpose of this study is to explore the mechanism of CyPA in SiO2-induced macrophage foaming and its effect on silicosis. We found that overexpression of CyPA promoted the macrophage foaming and the expression of COL I and α-SMA, while silencing CyPA inhibites the macrophage foaming and the expression of COL I and α-SMA. After blocking the expression of CD36 on the basis of overexpression CyPA, we found it inhibites the macrophage foaming. In conclusion, CyPA can affect the foaming of macrophages and may participate in silicosis fibrosis.
Collapse
Affiliation(s)
- Heliang Liu
- School of Public Health, North China University of Science and Technology, Tangshan, Hebei 063210, China; Hebei Key Laboratory of Organ Fibrosis, North China University of Science and Technology, Tangshan, Hebei 063210, China
| | - Hailan He
- School of Public Health, North China University of Science and Technology, Tangshan, Hebei 063210, China
| | - Ying Tian
- School of Public Health, North China University of Science and Technology, Tangshan, Hebei 063210, China
| | - Jie Cui
- School of Public Health, North China University of Science and Technology, Tangshan, Hebei 063210, China
| | - Shuang Wang
- School of Public Health, North China University of Science and Technology, Tangshan, Hebei 063210, China
| | - Hongli Wang
- School of Public Health, North China University of Science and Technology, Tangshan, Hebei 063210, China.
| |
Collapse
|
5
|
Kim JH, Kim DH, Lim YH, Shin CH, Lee YA, Kim BN, Kim JI, Hong YC. Childhood Obesity-Related Mechanisms: MicroRNome and Transcriptome Changes in a Nested Case-Control Study. Biomedicines 2021; 9:biomedicines9080878. [PMID: 34440082 PMCID: PMC8389653 DOI: 10.3390/biomedicines9080878] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 07/19/2021] [Accepted: 07/20/2021] [Indexed: 11/20/2022] Open
Abstract
Childhood obesity could contribute to adulthood obesity, leading to adverse health outcomes in adults. However, the mechanisms for how obesity is developed are still unclear. To determine the epigenome-wide and genome-wide expression changes related with childhood obesity, we compared microRNome and transcriptome levels as well as leptin protein levels in whole bloods of 12 obese and 24 normal children aged 6 years. miR-328-3p, miR-1301-3p, miR-4685-3p, and miR-6803-3p were negatively associated with all obesity indicators. The four miRNAs were also associated with 3948 mRNAs, and separate 475 mRNAs (185 among 3948 mRNAs) were associated with all obesity indicators. The 2533 mRNAs (64.2%) among the 3948 mRNAs and 286 mRNAs (60.2%) among the 475 mRNAs were confirmed as targets of the four miRNAs in public databases through miRWalk 2.0. Leptin protein was associated with miR-6803-3p negatively and all obesity indicators positively. Using DAVID bioinformatics resources 6.8, top three pathways for obesity-related gene set were metabolic pathways, pathways in cancer, and PI3K-Akt signaling pathway. The top three obesity-related disease classes were metabolic, cardiovascular, and chemdependency. Our results support that childhood obesity could be developed through miRNAs-related epigenetic mechanism and, further, these obesity-related epigenetic changes could control the pathways related with the development of various diseases.
Collapse
Affiliation(s)
- Jin Hee Kim
- Department of Integrative Bioscience & Biotechnology, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul 05006, Korea;
- Correspondence: (J.H.K.); (Y.-C.H.)
| | - Da Hae Kim
- Department of Integrative Bioscience & Biotechnology, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul 05006, Korea;
| | - Youn-Hee Lim
- Institute of Environmental Medicine, Seoul National University Medical Research Center, Seoul 03080, Korea;
- Environmental Health Center, Seoul National University College of Medicine, Seoul 03080, Korea
| | - Choong Ho Shin
- Department of Pediatrics, Seoul National University College of Medicine, Seoul 03080, Korea; (C.H.S.); (Y.A.L.)
| | - Young Ah Lee
- Department of Pediatrics, Seoul National University College of Medicine, Seoul 03080, Korea; (C.H.S.); (Y.A.L.)
| | - Bung-Nyun Kim
- Division of Children and Adolescent Psychiatry, Department of Psychiatry, Seoul National University Hospital, Seoul 03080, Korea;
| | - Johanna Inhyang Kim
- Department of Psychiatry, Hanyang University Medical Center, Seoul 04763, Korea;
| | - Yun-Chul Hong
- Institute of Environmental Medicine, Seoul National University Medical Research Center, Seoul 03080, Korea;
- Environmental Health Center, Seoul National University College of Medicine, Seoul 03080, Korea
- Department of Preventive Medicine, Seoul National University College of Medicine, Seoul 03080, Korea
- Correspondence: (J.H.K.); (Y.-C.H.)
| |
Collapse
|
6
|
Lloyd NR, Wuttke DS. Cyp33 binds AU-rich RNA motifs via an extended interface that competitively disrupts the gene repressive Cyp33-MLL1 interaction in vitro. PLoS One 2021; 16:e0237956. [PMID: 33606679 PMCID: PMC7894885 DOI: 10.1371/journal.pone.0237956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 01/25/2021] [Indexed: 11/19/2022] Open
Abstract
Cyp33 is an essential human cyclophilin prolyl isomerase that plays myriad roles in splicing and chromatin remodeling. In addition to a canonical cyclophilin (Cyp) domain, Cyp33 contains an RNA-recognition motif (RRM) domain, and RNA-binding triggers proline isomerase activity. One prominent role for Cyp33 is through a direct interaction with the mixed lineage leukemia protein 1 (MLL1, also known as KMT2A) complex, which is a histone methyltransferase that serves as a global regulator of human transcription. MLL activity is regulated by Cyp33, which isomerizes a key proline in the linker between the PHD3 and Bromo domains of MLL1, acting as a switch between gene activation and repression. The direct interaction between MLL1 and Cyp33 is critical, as deletion of the MLL1-PHD3 domain responsible for this interaction results in oncogenesis. The Cyp33 RRM is central to these activities, as it binds both the PHD3 domain and RNA. To better understand how RNA binding drives the action of Cyp33, we performed RNA-SELEX against full-length Cyp33 accompanied by deep sequencing. We have identified an enriched Cyp33 binding motif (AAUAAUAA) broadly represented in the cellular RNA pool as well as tightly binding RNA aptamers with affinities comparable and competitive with the Cyp33 MLL1-PHD3 interaction. RNA binding extends beyond the canonical RRM domain, but not to the Cyp domain, suggesting an indirect mechanism of interaction. NMR chemical shift mapping confirms an overlapping, but not identical, interface on Cyp33 for RNA and PHD3 binding. This finding suggests RNA can disrupt the gene repressive Cyp33-MLL1 complex providing another layer of regulation for chromatin remodeling by MLL1.
Collapse
Affiliation(s)
- Neil R. Lloyd
- Department of Biochemistry, UCB 596, University of Colorado Boulder, Boulder, Colorado, United States of America
| | - Deborah S. Wuttke
- Department of Biochemistry, UCB 596, University of Colorado Boulder, Boulder, Colorado, United States of America
- * E-mail:
| |
Collapse
|
7
|
Singh H, Kaur K, Singh M, Kaur G, Singh P. Plant Cyclophilins: Multifaceted Proteins With Versatile Roles. FRONTIERS IN PLANT SCIENCE 2020; 11:585212. [PMID: 33193535 PMCID: PMC7641896 DOI: 10.3389/fpls.2020.585212] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 09/22/2020] [Indexed: 05/03/2023]
Abstract
Cyclophilins constitute a family of ubiquitous proteins that bind cyclosporin A (CsA), an immunosuppressant drug. Several of these proteins possess peptidyl-prolyl cis-trans isomerase (PPIase) activity that catalyzes the cis-trans isomerization of the peptide bond preceding a proline residue, essential for correct folding of the proteins. Compared to prokaryotes and other eukaryotes studied until now, the cyclophilin gene families in plants exhibit considerable expansion. With few exceptions, the role of the majority of these proteins in plants is still a matter of conjecture. However, recent studies suggest that cyclophilins are highly versatile proteins with multiple functionalities, and regulate a plethora of growth and development processes in plants, ranging from hormone signaling to the stress response. The present review discusses the implications of cyclophilins in different facets of cellular processes, particularly in the context of plants, and provides a glimpse into the molecular mechanisms by which these proteins fine-tune the diverse physiological pathways.
Collapse
Affiliation(s)
- Harpreet Singh
- Department of Biotechnology, Guru Nanak Dev University, Amritsar, India
- Department of Bioinformatics, Hans Raj Mahila Maha Vidyalaya, Jalandhar, India
| | - Kirandeep Kaur
- Department of Biotechnology, Guru Nanak Dev University, Amritsar, India
| | - Mangaljeet Singh
- Department of Biotechnology, Guru Nanak Dev University, Amritsar, India
| | - Gundeep Kaur
- Department of Biotechnology, Guru Nanak Dev University, Amritsar, India
- William Harvey Heart Centre, Queen Mary University of London, London, United Kingdom
| | - Prabhjeet Singh
- Department of Biotechnology, Guru Nanak Dev University, Amritsar, India
| |
Collapse
|
8
|
Structural and Functional Insights into Human Nuclear Cyclophilins. Biomolecules 2018; 8:biom8040161. [PMID: 30518120 PMCID: PMC6315705 DOI: 10.3390/biom8040161] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 11/21/2018] [Accepted: 11/22/2018] [Indexed: 02/05/2023] Open
Abstract
The peptidyl prolyl isomerases (PPI) of the cyclophilin type are distributed throughout human cells, including eight found solely in the nucleus. Nuclear cyclophilins are involved in complexes that regulate chromatin modification, transcription, and pre-mRNA splicing. This review collects what is known about the eight human nuclear cyclophilins: peptidyl prolyl isomerase H (PPIH), peptidyl prolyl isomerase E (PPIE), peptidyl prolyl isomerase-like 1 (PPIL1), peptidyl prolyl isomerase-like 2 (PPIL2), peptidyl prolyl isomerase-like 3 (PPIL3), peptidyl prolyl isomerase G (PPIG), spliceosome-associated protein CWC27 homolog (CWC27), and peptidyl prolyl isomerase domain and WD repeat-containing protein 1 (PPWD1). Each “spliceophilin” is evaluated in relation to the spliceosomal complex in which it has been studied, and current work studying the biological roles of these cyclophilins in the nucleus are discussed. The eight human splicing complexes available in the Protein Data Bank (PDB) are analyzed from the viewpoint of the human spliceophilins. Future directions in structural and cellular biology, and the importance of developing spliceophilin-specific inhibitors, are considered.
Collapse
|
9
|
Dilworth D, Upadhyay SK, Bonnafous P, Edoo AB, Bourbigot S, Pesek-Jardim F, Gudavicius G, Serpa JJ, Petrotchenko EV, Borchers CH, Nelson CJ, Mackereth CD. The basic tilted helix bundle domain of the prolyl isomerase FKBP25 is a novel double-stranded RNA binding module. Nucleic Acids Res 2017; 45:11989-12004. [PMID: 29036638 PMCID: PMC5714180 DOI: 10.1093/nar/gkx852] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Accepted: 09/13/2017] [Indexed: 11/14/2022] Open
Abstract
Prolyl isomerases are defined by a catalytic domain that facilitates the cis–trans interconversion of proline residues. In most cases, additional domains in these enzymes add important biological function, including recruitment to a set of protein substrates. Here, we report that the N-terminal basic tilted helix bundle (BTHB) domain of the human prolyl isomerase FKBP25 confers specific binding to double-stranded RNA (dsRNA). This binding is selective over DNA as well as single-stranded oligonucleotides. We find that FKBP25 RNA-association is required for its nucleolar localization and for the vast majority of its protein interactions, including those with 60S pre-ribosome and early ribosome biogenesis factors. An independent mobility of the BTHB and FKBP catalytic domains supports a model by which the N-terminus of FKBP25 is anchored to regions of dsRNA, whereas the FKBP domain is free to interact with neighboring proteins. Apart from the identification of the BTHB as a new dsRNA-binding module, this domain adds to the growing list of auxiliary functions used by prolyl isomerases to define their primary cellular targets.
Collapse
Affiliation(s)
- David Dilworth
- Dept. of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8W 3P6, Canada
| | - Santosh K Upadhyay
- Univ. Bordeaux, Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, F-33607 Pessac, France.,Inserm U1212, CNRS UMR 5320, ARNA Laboratory, Univ. Bordeaux, 146 rue Léo Saignat, F-33076 Bordeaux, France.,CSIR-Institute of Genomics and Integrative Biology, New Delhi 110020, India
| | - Pierre Bonnafous
- Univ. Bordeaux, Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, F-33607 Pessac, France.,Inserm U1212, CNRS UMR 5320, ARNA Laboratory, Univ. Bordeaux, 146 rue Léo Saignat, F-33076 Bordeaux, France
| | - Amiirah Bibi Edoo
- Univ. Bordeaux, Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, F-33607 Pessac, France.,Inserm U1212, CNRS UMR 5320, ARNA Laboratory, Univ. Bordeaux, 146 rue Léo Saignat, F-33076 Bordeaux, France
| | - Sarah Bourbigot
- Univ. Bordeaux, Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, F-33607 Pessac, France.,Inserm U1212, CNRS UMR 5320, ARNA Laboratory, Univ. Bordeaux, 146 rue Léo Saignat, F-33076 Bordeaux, France
| | - Francy Pesek-Jardim
- Dept. of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8W 3P6, Canada
| | - Geoff Gudavicius
- Dept. of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8W 3P6, Canada
| | - Jason J Serpa
- Dept. of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8W 3P6, Canada.,University of Victoria Genome BC Proteomics Centre, Vancouver Island Technology Park, Victoria, BC V8Z 7X8, Canada
| | - Evgeniy V Petrotchenko
- Dept. of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8W 3P6, Canada.,University of Victoria Genome BC Proteomics Centre, Vancouver Island Technology Park, Victoria, BC V8Z 7X8, Canada
| | - Christoph H Borchers
- Dept. of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8W 3P6, Canada.,University of Victoria Genome BC Proteomics Centre, Vancouver Island Technology Park, Victoria, BC V8Z 7X8, Canada
| | - Christopher J Nelson
- Dept. of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8W 3P6, Canada
| | - Cameron D Mackereth
- Univ. Bordeaux, Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, F-33607 Pessac, France.,Inserm U1212, CNRS UMR 5320, ARNA Laboratory, Univ. Bordeaux, 146 rue Léo Saignat, F-33076 Bordeaux, France
| |
Collapse
|
10
|
Blackburn EA, Wear MA, Landré V, Narayan V, Ning J, Erman B, Ball KL, Walkinshaw MD. Cyclophilin40 isomerase activity is regulated by a temperature-dependent allosteric interaction with Hsp90. Biosci Rep 2015; 35:e00258. [PMID: 26330616 PMCID: PMC4721547 DOI: 10.1042/bsr20150124] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Revised: 06/19/2015] [Accepted: 07/03/2015] [Indexed: 02/06/2023] Open
Abstract
Cyclophilin 40 (Cyp40) comprises an N-terminal cyclophilin domain with peptidyl-prolyl isomerase (PPIase) activity and a C-terminal tetratricopeptide repeat (TPR) domain that binds to the C-terminal-EEVD sequence common to both heat shock protein 70 (Hsp70) and Hsp90. We show in the present study that binding of peptides containing the MEEVD motif reduces the PPIase activity by ∼30%. CD and fluorescence assays show that the TPR domain is less stable than the cyclophilin domain and is stabilized by peptide binding. Isothermal titration calorimetry (ITC) shows that the affinity for the-MEEVD peptide is temperature sensitive in the physiological temperature range. Results from these biophysical studies fit with the MD simulations of the apo and holo (peptide-bound) structures which show a significant reduction in root mean square (RMS) fluctuation in both TPR and cyclophilin domains when-MEEVD is bound. The MD simulations of the apo-protein also highlight strong anti-correlated motions between residues around the PPIase-active site and a band of residues running across four of the seven helices in the TPR domain. Peptide binding leads to a distortion in the shape of the active site and a significant reduction in these strongly anti-correlated motions, providing an explanation for the allosteric effect of ligand binding and loss of PPIase activity. Together the experimental and MD results suggest that on heat shock, dissociation of Cyp40 from complexes mediated by the TPR domain leads to an increased pool of free Cyp40 capable of acting as an isomerase/chaperone in conditions of cellular stress.
Collapse
Affiliation(s)
- Elizabeth A Blackburn
- Centre for Translational and Chemical Biology, School of Biological Sciences, University of Edinburgh, Michael Swann Building, The King's Buildings, Mayfield Road, Edinburgh EH9 3JR, U.K
| | - Martin A Wear
- Centre for Translational and Chemical Biology, School of Biological Sciences, University of Edinburgh, Michael Swann Building, The King's Buildings, Mayfield Road, Edinburgh EH9 3JR, U.K
| | - Vivian Landré
- IGMM-Edinburgh Cancer Research Centre, University of Edinburgh, Crewe Road South, EH4 2XR, U.K
| | - Vikram Narayan
- IGMM-Edinburgh Cancer Research Centre, University of Edinburgh, Crewe Road South, EH4 2XR, U.K
| | - Jia Ning
- Centre for Translational and Chemical Biology, School of Biological Sciences, University of Edinburgh, Michael Swann Building, The King's Buildings, Mayfield Road, Edinburgh EH9 3JR, U.K
| | - Burak Erman
- Chemical and Biological Engineering Department, Koc University, Istanbul 34415, Turkey
| | - Kathryn L Ball
- IGMM-Edinburgh Cancer Research Centre, University of Edinburgh, Crewe Road South, EH4 2XR, U.K
| | - Malcolm D Walkinshaw
- Centre for Translational and Chemical Biology, School of Biological Sciences, University of Edinburgh, Michael Swann Building, The King's Buildings, Mayfield Road, Edinburgh EH9 3JR, U.K.
| |
Collapse
|
11
|
Roles of Prolyl Isomerases in RNA-Mediated Gene Expression. Biomolecules 2015; 5:974-99. [PMID: 25992900 PMCID: PMC4496705 DOI: 10.3390/biom5020974] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Revised: 05/01/2015] [Accepted: 05/07/2015] [Indexed: 12/16/2022] Open
Abstract
The peptidyl-prolyl cis-trans isomerases (PPIases) that include immunophilins (cyclophilins and FKBPs) and parvulins (Pin1, Par14, Par17) participate in cell signaling, transcription, pre-mRNA processing and mRNA decay. The human genome encodes 19 cyclophilins, 18 FKBPs and three parvulins. Immunophilins are receptors for the immunosuppressive drugs cyclosporin A, FK506, and rapamycin that are used in organ transplantation. Pin1 has also been targeted in the treatment of Alzheimer’s disease, asthma, and a number of cancers. While these PPIases are characterized as molecular chaperones, they also act in a nonchaperone manner to promote protein-protein interactions using surfaces outside their active sites. The immunosuppressive drugs act by a gain-of-function mechanism by promoting protein-protein interactions in vivo. Several immunophilins have been identified as components of the spliceosome and are essential for alternative splicing. Pin1 plays roles in transcription and RNA processing by catalyzing conformational changes in the RNA Pol II C-terminal domain. Pin1 also binds several RNA binding proteins such as AUF1, KSRP, HuR, and SLBP that regulate mRNA decay by remodeling mRNP complexes. The functions of ribonucleoprotein associated PPIases are largely unknown. This review highlights PPIases that play roles in RNA-mediated gene expression, providing insight into their structures, functions and mechanisms of action in mRNP remodeling in vivo.
Collapse
|
12
|
Ulrich A, Wahl MC. Structure and evolution of the spliceosomal peptidyl-prolyl cis-trans isomerase Cwc27. ACTA ACUST UNITED AC 2014; 70:3110-23. [PMID: 25478830 DOI: 10.1107/s1399004714021695] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 10/01/2014] [Indexed: 11/10/2022]
Abstract
Cwc27 is a spliceosomal cyclophilin-type peptidyl-prolyl cis-trans isomerase (PPIase). Here, the crystal structure of a relatively protease-resistant N-terminal fragment of human Cwc27 containing the PPIase domain was determined at 2.0 Å resolution. The fragment exhibits a C-terminal appendix and resides in a reduced state compared with the previous oxidized structure of a similar fragment. By combining multiple sequence alignments spanning the eukaryotic tree of life and secondary-structure prediction, Cwc27 proteins across the entire eukaryotic kingdom were identified. This analysis revealed the specific loss of a crucial active-site residue in higher eukaryotic Cwc27 proteins, suggesting that the protein evolved from a prolyl isomerase to a pure proline binder. Noting a fungus-specific insertion in the PPIase domain, the 1.3 Å resolution crystal structure of the PPIase domain of Cwc27 from Chaetomium thermophilum was also determined. Although structurally highly similar in the core domain, the C. thermophilum protein displayed a higher thermal stability than its human counterpart, presumably owing to the combined effect of several amino-acid exchanges that reduce the number of long side chains with strained conformations and create new intramolecular interactions, in particular increased hydrogen-bond networks.
Collapse
Affiliation(s)
- Alexander Ulrich
- Laboratory of Structural Biochemistry, Freie Universität Berlin, Takustrasse 6, 14195 Berlin, Germany
| | - Markus C Wahl
- Laboratory of Structural Biochemistry, Freie Universität Berlin, Takustrasse 6, 14195 Berlin, Germany
| |
Collapse
|
13
|
Schiene-Fischer C. Multidomain Peptidyl Prolyl cis/trans Isomerases. Biochim Biophys Acta Gen Subj 2014; 1850:2005-16. [PMID: 25445709 DOI: 10.1016/j.bbagen.2014.11.012] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Revised: 11/10/2014] [Accepted: 11/13/2014] [Indexed: 10/24/2022]
Abstract
BACKGROUND Peptidyl prolyl cis/trans isomerases (PPIases) assist the folding and restructuring of client proteins by catalysis of the slow rotational motion of peptide bonds preceding a proline residue. Catalysis is performed by relatively small, distinct protein domains of 10 to 18kDa for all PPIase families. PPIases are involved in a wide variety of physiological and pathophysiological processes like signal transduction, cell differentiation, apoptosis as well as viral, bacterial and parasitic infection. SCOPE OF REVIEW There are multidomain PPIases consisting of one to up to four catalytic domains of the respective PPIase family supplemented by N- or C-terminal extensions. This review examines the biochemical and functional properties of the members of the PPIase class of enzymes which contain additional protein domains with defined biochemical functions. MAJOR CONCLUSIONS The versatile domain architecture of multidomain PPIases is important for the control of enzyme specificity and organelle-specific targeting, the establishment of molecular connections and hence the coordination of PPIase functions across the cellular network. GENERAL SIGNIFICANCE Accessory domains covalently linked to a PPIase domain supply an additional layer of control to the catalysis of prolyl isomerization in specific client proteins. Understanding these control mechanisms will provide new insights into the physiological mode of action of the multidomain PPIases and their ability to form therapeutic targets. This article is part of a Special Issue entitled Proline-directed Foldases: Cell Signaling Catalysts and Drug Targets.
Collapse
Affiliation(s)
- Cordelia Schiene-Fischer
- Department of Enzymology, Institute for Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Weinbergweg 22, 06120 Halle (Saale), Germany.
| |
Collapse
|
14
|
Cyclophilins as modulators of viral replication. Viruses 2013; 5:1684-701. [PMID: 23852270 PMCID: PMC3738956 DOI: 10.3390/v5071684] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Revised: 06/26/2013] [Accepted: 07/03/2013] [Indexed: 01/11/2023] Open
Abstract
Cyclophilins are peptidyl‐prolyl cis/trans isomerases important in the proper folding of certain proteins. Mounting evidence supports varied roles of cyclophilins, either positive or negative, in the life cycles of diverse viruses, but the nature and mechanisms of these roles are yet to be defined. The potential for cyclophilins to serve as a drug target for antiviral therapy is evidenced by the success of non-immunosuppressive cyclophilin inhibitors (CPIs), including Alisporivir, in clinical trials targeting hepatitis C virus infection. In addition, as cyclophilins are implicated in the predisposition to, or severity of, various diseases, the ability to specifically and effectively modulate their function will prove increasingly useful for disease intervention. In this review, we will summarize the evidence of cyclophilins as key mediators of viral infection and prospective drug targets.
Collapse
|
15
|
Bannikova O, Zywicki M, Marquez Y, Skrahina T, Kalyna M, Barta A. Identification of RNA targets for the nuclear multidomain cyclophilin atCyp59 and their effect on PPIase activity. Nucleic Acids Res 2012; 41:1783-96. [PMID: 23248006 PMCID: PMC3561992 DOI: 10.1093/nar/gks1252] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
AtCyp59 is a multidomain cyclophilin containing a peptidyl-prolyl cis/trans isomerase (PPIase) domain and an evolutionarily highly conserved RRM domain. Deregulation of this class of cyclophilins has been shown to affect transcription and to influence phosphorylation of the C-terminal repeat domain of the largest subunit of the RNA polymerase II. We used a genomic SELEX method for identifying RNA targets of AtCyp59. Analysis of the selected RNAs revealed an RNA-binding motif (G[U/C]N[G/A]CC[A/G]) and we show that it is evolutionarily conserved. Binding to this motif was verified by gel shift assays in vitro and by RNA immunopreciptation assays of AtCyp59 in vivo. Most importantly, we show that binding also occurs on unprocessed transcripts in vivo and that binding of specific RNAs inhibits the PPIase activity of AtCyp59 in vitro. Surprisingly, genome-wide analysis showed that the RNA motif is present in about 70% of the annotated transcripts preferentially in exons. Taken together, the available data suggest that these cyclophilins might have an important function in transcription regulation.
Collapse
Affiliation(s)
- Olga Bannikova
- Max F. Perutz Laboratories, Medical University of Vienna, Vienna, Austria
| | | | | | | | | | | |
Collapse
|
16
|
Ferreira PA, Orry A. From Drosophila to humans: reflections on the roles of the prolyl isomerases and chaperones, cyclophilins, in cell function and disease. J Neurogenet 2012; 26:132-43. [PMID: 22332926 DOI: 10.3109/01677063.2011.647143] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Despite remarkable advances in human genetics and other genetic model systems, the fruit fly, Drosophila melanogaster, remains a powerful experimental tool to probe with ease the inner workings of a myriad of biological and pathological processes, even when evolutionary forces impart apparent divergences to some of such processes. The understanding of such evolutionary differences provides mechanistic insights into genotype-phenotype correlations underpinning biological processes across metazoans. The pioneering work developed by the William Pak laboratory for the past four decades, and the work of others, epitomize the notion of how the Drosophila system breaks new fertile ground or complements research fields of high scientific and medical relevance. Among the three major genetic complementation groups produced by the Pak's laboratory and impairing distinct facets of photoreceptor neuronal function, the nina group (ninaA, …., ninaJ) selectively affects the biogenesis of G protein-coupled receptors (GPCRs), mediating the photoconversion and transduction of light stimuli. Among the nina genes identified, ninaA arguably assumes heightened significance for several reasons. First, it presents unique physiological selectivity toward the biogenesis of a subset of GPCRs, a standalone biological manifestation yet to be discerned for most mammalian homologues of NinaA. Second, NinaA belongs to a family of proteins, immunophilins, which are the primary targets for immunosuppressive drugs at the therapeutic forefront of a multitude of medical conditions. Third, NinaA closest homologue, cyclophilin B (CyPB/PPIB), is an immunophilin whose loss-of-function was found recently to cause osteogenesis imperfecta in the human. This report highlights advances made by studies on some members of immunophilins, the cyclophilins. Finally, it reexamines critically data and dogmas derived from past and recent genetic, structural, biological, and pathological studies on NinaA and few other cyclophilins that support some of such paradigms to be less than definite and advance our understanding of the roles of cyclophilins in cell function, disease, and therapeutic interventions.
Collapse
Affiliation(s)
- Paulo A Ferreira
- Department of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA.
| | | |
Collapse
|
17
|
Dilworth D, Gudavicius G, Leung A, Nelson CJ. The roles of peptidyl-proline isomerases in gene regulation. Biochem Cell Biol 2011; 90:55-69. [PMID: 21999350 DOI: 10.1139/o11-045] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The post-translational modification of proteins and enzymes provides a dynamic and reversible means to control protein function and transmit biological signals. While covalent modifications such as phosphorylation and acetylation have drawn much attention, in the past decade the involvement of peptidyl-proline isomerases (PPIs) in signaling and post-translational modification of protein function has become increasingly apparent. Three distinct families of PPI enzymes (parvulins, cyclophilins, and FK506-binding proteins (FKBPs)) each have the capacity to catalyze cis-trans proline isomerization in substrate proteins, and this modification can regulate both structure and function. In eukaryotic cells, a subset of these enzymes is localized to the nucleus, where they regulate gene expression at multiple control points. Here we summarize this body of work that together establishes a clear role of these enzymes as evolutionarily conserved players in the control of both transcription of mRNAs and the assembly of chromatin.
Collapse
Affiliation(s)
- David Dilworth
- The Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8W 3P6, Canada
| | | | | | | |
Collapse
|
18
|
Abstract
Cyclophilins (Cyps) belong to a group of proteins that have peptidyl-prolyl cis–trans isomerase (PPIase) and molecular chaperone activities. Originally, Cyps were identified as the intracellular receptors for the immunosuppressive drug cyclosporin A. Cyps are found in all prokaryotes and eukaryotes, and have been structurally conserved throughout evolution, implying their importance in cellular function. There are seven major Cyp isoforms in humans. CypA is up-regulated in many human cancers, and there is a strong correlation between over-expression of the CYPA gene and malignant transformation in some cancers. Moreover, CypA is directly under the transcriptional control of two critical transcription factors for cancer development: p53 and hypoxia inducible factor-1α. This review discusses the general biological functions of Cyps under a variety of stress conditions, and the importance and diverse roles of over-expression of CYP genes in human cancers, with a particular emphasis on CYPA. These oncogenic properties suggest that CypA is a promising target for cancer therapy.
Collapse
Affiliation(s)
- J Lee
- Department of Biomedical Laboratory Science, Dongseo University, Busan, Republic of Korea
| | - SS Kim
- Department of Biochemistry and Molecular Biology, Medical Science and Engineering Research Centre for Bioreaction to Reactive Oxygen Species (BK-21) and Biomedical Science Institute, School of Medicine, Kyung Hee University, Seoul, Republic of Korea
| |
Collapse
|
19
|
Davis TL, Walker JR, Campagna-Slater V, Finerty PJ, Paramanathan R, Bernstein G, MacKenzie F, Tempel W, Ouyang H, Lee WH, Eisenmesser EZ, Dhe-Paganon S. Structural and biochemical characterization of the human cyclophilin family of peptidyl-prolyl isomerases. PLoS Biol 2010; 8:e1000439. [PMID: 20676357 PMCID: PMC2911226 DOI: 10.1371/journal.pbio.1000439] [Citation(s) in RCA: 193] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2009] [Accepted: 06/16/2010] [Indexed: 11/29/2022] Open
Abstract
Peptidyl-prolyl isomerases catalyze the conversion between cis and trans isomers of proline. The cyclophilin family of peptidyl-prolyl isomerases is well known for being the target of the immunosuppressive drug cyclosporin, used to combat organ transplant rejection. There is great interest in both the substrate specificity of these enzymes and the design of isoform-selective ligands for them. However, the dearth of available data for individual family members inhibits attempts to design drug specificity; additionally, in order to define physiological functions for the cyclophilins, definitive isoform characterization is required. In the current study, enzymatic activity was assayed for 15 of the 17 human cyclophilin isomerase domains, and binding to the cyclosporin scaffold was tested. In order to rationalize the observed isoform diversity, the high-resolution crystallographic structures of seven cyclophilin domains were determined. These models, combined with seven previously solved cyclophilin isoforms, provide the basis for a family-wide structure:function analysis. Detailed structural analysis of the human cyclophilin isomerase explains why cyclophilin activity against short peptides is correlated with an ability to ligate cyclosporin and why certain isoforms are not competent for either activity. In addition, we find that regions of the isomerase domain outside the proline-binding surface impart isoform specificity for both in vivo substrates and drug design. We hypothesize that there is a well-defined molecular surface corresponding to the substrate-binding S2 position that is a site of diversity in the cyclophilin family. Computational simulations of substrate binding in this region support our observations. Our data indicate that unique isoform determinants exist that may be exploited for development of selective ligands and suggest that the currently available small-molecule and peptide-based ligands for this class of enzyme are insufficient for isoform specificity.
Collapse
Affiliation(s)
- Tara L. Davis
- Structural Genomics Consortium, University of Toronto, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - John R. Walker
- Structural Genomics Consortium, University of Toronto, Toronto, Ontario, Canada
| | | | - Patrick J. Finerty
- Structural Genomics Consortium, University of Toronto, Toronto, Ontario, Canada
| | - Ragika Paramanathan
- Structural Genomics Consortium, University of Toronto, Toronto, Ontario, Canada
| | - Galina Bernstein
- Structural Genomics Consortium, University of Toronto, Toronto, Ontario, Canada
| | - Farrell MacKenzie
- Structural Genomics Consortium, University of Toronto, Toronto, Ontario, Canada
| | - Wolfram Tempel
- Structural Genomics Consortium, University of Toronto, Toronto, Ontario, Canada
| | - Hui Ouyang
- Structural Genomics Consortium, University of Toronto, Toronto, Ontario, Canada
| | - Wen Hwa Lee
- Structural Genomics Consortium, University of Toronto, Toronto, Ontario, Canada
- University of Oxford, Headington, United Kingdom
| | - Elan Z. Eisenmesser
- Department of Biochemistry & Molecular Genetics, University of Colorado Denver, Aurora, Colorado, United States of America
| | - Sirano Dhe-Paganon
- Structural Genomics Consortium, University of Toronto, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| |
Collapse
|
20
|
Abstract
The MLL1 (mixed lineage leukemia 1) protein, which is often disrupted in leukemia, both activates and represses Hox genes during hematopoiesis. Now, Wang et al. (2010) demonstrate that the cyclophilin CyP33 underpins this regulatory switch by altering the state of MLL1 through cis-trans proline isomerization in the linker region between MLL1's third PHD finger and bromodomain.
Collapse
|
21
|
Wang Z, Song J, Milne TA, Wang GG, Li H, Allis CD, Patel DJ. Pro isomerization in MLL1 PHD3-bromo cassette connects H3K4me readout to CyP33 and HDAC-mediated repression. Cell 2010; 141:1183-94. [PMID: 20541251 DOI: 10.1016/j.cell.2010.05.016] [Citation(s) in RCA: 150] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2009] [Revised: 02/19/2010] [Accepted: 04/19/2010] [Indexed: 01/27/2023]
Abstract
The MLL1 gene is a frequent target for recurrent chromosomal translocations, resulting in transformation of hematopoietic precursors into leukemia stem cells. Here, we report on structure-function studies that elucidate molecular events in MLL1 binding of histone H3K4me3/2 marks and recruitment of the cyclophilin CyP33. CyP33 contains a PPIase and a RRM domain and regulates MLL1 function through HDAC recruitment. We find that the PPIase domain of CyP33 regulates the conformation of MLL1 through proline isomerization within the PHD3-Bromo linker, thereby disrupting the PHD3-Bromo interface and facilitating binding of the MLL1-PHD3 domain to the CyP33-RRM domain. H3K4me3/2 and CyP33-RRM target different surfaces of MLL1-PHD3 and can bind simultaneously to form a ternary complex. Furthermore, the MLL1-CyP33 interaction is required for repression of HOXA9 and HOXC8 genes in vivo. Our results highlight the role of PHD3-Bromo cassette as a regulatory platform, orchestrating MLL1 binding of H3K4me3/2 marks and cyclophilin-mediated repression through HDAC recruitment.
Collapse
Affiliation(s)
- Zhanxin Wang
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA
| | | | | | | | | | | | | |
Collapse
|
22
|
Hom RA, Chang PY, Roy S, Musselman CA, Glass KC, Selezneva AI, Gozani O, Ismagilov RF, Cleary ML, Kutateladze TG. Molecular mechanism of MLL PHD3 and RNA recognition by the Cyp33 RRM domain. J Mol Biol 2010; 400:145-54. [PMID: 20460131 DOI: 10.1016/j.jmb.2010.04.067] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2010] [Revised: 04/30/2010] [Accepted: 04/30/2010] [Indexed: 12/22/2022]
Abstract
The nuclear protein cyclophilin 33 (Cyp33) is a peptidyl-prolyl cis-trans isomerase that catalyzes cis-trans isomerization of the peptide bond preceding a proline and promotes folding and conformational changes in folded and unfolded proteins. The N-terminal RNA-recognition motif (RRM) domain of Cyp33 has been found to associate with the third plant homeodomain (PHD3) finger of the mixed lineage leukemia (MLL) proto-oncoprotein and a poly(A) RNA sequence. Here, we report a 1.9 A resolution crystal structure of the RRM domain of Cyp33 and describe the molecular mechanism of PHD3 and RNA recognition. The Cyp33 RRM domain folds into a five-stranded antiparallel beta-sheet and two alpha-helices. The RRM domain, but not the catalytic module of Cyp33, binds strongly to PHD3, exhibiting a 2 muM affinity as measured by isothermal titration calorimetry. NMR chemical shift perturbation (CSP) analysis and dynamics data reveal that the beta strands and the beta2-beta3 loop of the RRM domain are involved in the interaction with PHD3. Mutations in the PHD3-binding site or deletions in the beta2-beta3 loop lead to a significantly reduced affinity or abrogation of the interaction. The RNA-binding pocket of the Cyp33 RRM domain, mapped on the basis of NMR CSP and mutagenesis, partially overlaps with the PHD3-binding site, and RNA association is abolished in the presence of MLL PHD3. Full-length Cyp33 acts as a negative regulator of MLL-induced transcription and reduces the expression levels of MLL target genes MEIS1 and HOXA9. Together, these in vitro and in vivo data provide insight into the multiple functions of Cyp33 RRM and suggest a Cyp33-dependent mechanism for regulating the transcriptional activity of MLL.
Collapse
Affiliation(s)
- Robert A Hom
- Department of Pharmacology, University of Colorado Denver School of Medicine, 12801 East 17th Avenue, Aurora, CO 80045, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|