1
|
Neuhaus D. Zinc finger structure determination by NMR: Why zinc fingers can be a handful. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2022; 130-131:62-105. [PMID: 36113918 PMCID: PMC7614390 DOI: 10.1016/j.pnmrs.2022.07.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 07/09/2022] [Accepted: 07/10/2022] [Indexed: 06/07/2023]
Abstract
Zinc fingers can be loosely defined as protein domains containing one or more tetrahedrally-co-ordinated zinc ions whose role is to stabilise the structure rather than to be involved in enzymatic chemistry; such zinc ions are often referred to as "structural zincs". Although structural zincs can occur in proteins of any size, they assume particular significance for very small protein domains, where they are often essential for maintaining a folded state. Such small structures, that sometimes have only marginal stability, can present particular difficulties in terms of sample preparation, handling and structure determination, and early on they gained a reputation for being resistant to crystallisation. As a result, NMR has played a more prominent role in structural studies of zinc finger proteins than it has for many other types of proteins. This review will present an overview of the particular issues that arise for structure determination of zinc fingers by NMR, and ways in which these may be addressed.
Collapse
Affiliation(s)
- David Neuhaus
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK.
| |
Collapse
|
2
|
Liu Y, Lan W, Wang C, Cao C. Two different kinds of interaction modes of deaminase APOBEC3A with single-stranded DNA in solution detected by nuclear magnetic resonance. Protein Sci 2022; 31:443-453. [PMID: 34792260 PMCID: PMC8819843 DOI: 10.1002/pro.4242] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 11/09/2021] [Accepted: 11/09/2021] [Indexed: 02/03/2023]
Abstract
APOBEC3A (A3A) deaminates deoxycytidine in target motif TC in a single-stranded DNA (we termed it as TC DNA), which mortally mutates viral pathogens and immunoglobulins, and leads to the diversification and lethality of cancers. The crystal structure of A3A-DNA revealed a unique U-shaped recognition mode of target base dC0 . However, when TC DNA was titrated into 15 N-labeled A3A solution, we observed two sets of 1 H-15 N cross-peaks of A3A in HSQC spectra, and two sets of 1 H-1 H cross-peaks of DNA in two-dimensional 13 C,15 N-filtered TOCSY spectra, indicating two different kinds of conformers of either A3A or TC DNA existing in solution. Here, mainly by NMR, we demonstrated that one DNA conformer interacted with one A3A conformer, forming a specific complex A3AS -DNAS in a way almost similar to that observed in the reported crystal A3A-DNA structure, where dC0 inserted into zinc ion binding center. While the other DNA conformer bound with another A3A conformer, but dC0 did not extend into the zinc-binding pocket, forming a nonspecific A3ANS -DNANS complex. The NMR solution structure implied three sites Asn61 , His182 and Arg189 were necessary to DNA recognition. These observations indicate a distinctive way from that reported in X-ray crystal structure, suggesting an unexpected mode of deaminase APOBEC3A to identify target motif TC in DNA in solution.
Collapse
Affiliation(s)
- Yaping Liu
- State Key Laboratory of Bioorganic and Natural Product ChemistryCenter for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of SciencesShanghaiChina,University of Chinese Academy of ScienceBeijingChina
| | - Wenxian Lan
- State Key Laboratory of Bioorganic and Natural Product ChemistryCenter for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of SciencesShanghaiChina
| | - Chunxi Wang
- State Key Laboratory of Bioorganic and Natural Product ChemistryCenter for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of SciencesShanghaiChina
| | - Chunyang Cao
- State Key Laboratory of Bioorganic and Natural Product ChemistryCenter for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of SciencesShanghaiChina,University of Chinese Academy of ScienceBeijingChina
| |
Collapse
|
3
|
Al-Naama N, Mackeh R, Kino T. C 2H 2-Type Zinc Finger Proteins in Brain Development, Neurodevelopmental, and Other Neuropsychiatric Disorders: Systematic Literature-Based Analysis. Front Neurol 2020; 11:32. [PMID: 32117005 PMCID: PMC7034409 DOI: 10.3389/fneur.2020.00032] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 01/10/2020] [Indexed: 12/15/2022] Open
Abstract
Neurodevelopmental disorders (NDDs) are multifaceted pathologic conditions manifested with intellectual disability, autistic features, psychiatric problems, motor dysfunction, and/or genetic/chromosomal abnormalities. They are associated with skewed neurogenesis and brain development, in part through dysfunction of the neural stem cells (NSCs) where abnormal transcriptional regulation on key genes play significant roles. Recent accumulated evidence highlights C2H2-type zinc finger proteins (C2H2-ZNFs), the largest transcription factor family in humans, as important targets for the pathologic processes associated with NDDs. In this review, we identified their significant accumulation (74 C2H2-ZNFs: ~10% of all human member proteins) in brain physiology and pathology. Specifically, we discuss their physiologic contribution to brain development, particularly focusing on their actions in NSCs. We then explain their pathologic implications in various forms of NDDs, such as morphological brain abnormalities, intellectual disabilities, and psychiatric disorders. We found an important tendency that poly-ZNFs and KRAB-ZNFs tend to be involved in the diseases that compromise gross brain structure and human-specific higher-order functions, respectively. This may be consistent with their characteristic appearance in the course of species evolution and corresponding contribution to these brain activities.
Collapse
Affiliation(s)
- Njoud Al-Naama
- Laboratory of Molecular and Genomic Endocrinology, Division of Translational Medicine, Sidra Medicine, Doha, Qatar
| | - Rafah Mackeh
- Laboratory of Molecular and Genomic Endocrinology, Division of Translational Medicine, Sidra Medicine, Doha, Qatar
| | - Tomoshige Kino
- Laboratory of Molecular and Genomic Endocrinology, Division of Translational Medicine, Sidra Medicine, Doha, Qatar
| |
Collapse
|
4
|
Yan X, Lan W, Wang C, Cao C. Structural Investigations on the Interactions between Cytidine Deaminase Human APOBEC3G and DNA. Chem Asian J 2019; 14:2235-2241. [PMID: 31116511 DOI: 10.1002/asia.201900480] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 05/20/2019] [Indexed: 02/05/2023]
Abstract
Human APOBEC3G (A3G) inhibits the replication of human immunodeficiency virus-1 by deaminating cytidine at the 3'-end in the target motif 5'-CCC-3' in viral cDNA during reverse transcription. It in vitro deaminates two consecutive cytidines in a 3'->5' order. Although a crystal structure of the A3G catalytic domain (A3G-CD2) with DNA was reported, it is unknown why residues involved in enzymatic reaction are distributed widely. Here, we introduced an iodine atom into the C-5 position of cytidine (dC6 I ) in DNA 5'-ATTC4 C5 C6 I A7 ATT-3' (TCCC6 I ). It switches the deamination sequence preference from CCC to TCC, although small dC6 I deamination was observed. Solution structures of A3G-CD2 in complexes with products DNA TCUC6 I and TCUU6 I indicate that the substrate DNA binds A3G-CD2 in TCC and CCC modes. The dC6 deamination correlates with the 4th base type. The CCC mode favours dC6 deamination, while the TCC mode results in dC5 deamination. These studies present an extensive basis to design inhibitors to impede viral evolvability.
Collapse
Affiliation(s)
- Xiaoxuan Yan
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Science, 345 Lingling Road, Shanghai, 200032, China.,University of Chinese Academy of Sciences, No. 19(A) Yuquan Road, Shijingshan District, Beijing, 100049, China
| | - Wenxian Lan
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Science, 345 Lingling Road, Shanghai, 200032, China
| | - Chunxi Wang
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Science, 345 Lingling Road, Shanghai, 200032, China
| | - Chunyang Cao
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Science, 345 Lingling Road, Shanghai, 200032, China.,University of Chinese Academy of Sciences, No. 19(A) Yuquan Road, Shijingshan District, Beijing, 100049, China
| |
Collapse
|
5
|
Mackeh R, Marr AK, Fadda A, Kino T. C2H2-Type Zinc Finger Proteins: Evolutionarily Old and New Partners of the Nuclear Hormone Receptors. NUCLEAR RECEPTOR SIGNALING 2018; 15:1550762918801071. [PMID: 30718982 PMCID: PMC6348741 DOI: 10.1177/1550762918801071] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 02/02/2017] [Indexed: 12/21/2022]
Abstract
Nuclear hormone receptors (NRs) are evolutionarily conserved ligand-dependent
transcription factors. They are essential for human life, mediating the actions
of lipophilic molecules, such as steroid hormones and metabolites of fatty acid,
cholesterol, and external toxic compounds. The C2H2-type zinc finger proteins
(ZNFs) form the largest family of the transcription factors in humans and are
characterized by multiple, tandemly arranged zinc fingers. Many of the C2H2-type
ZNFs are conserved throughout evolution, suggesting their involvement in
preserved biological activities, such as general transcriptional regulation and
development/differentiation of organs/tissues observed in the early embryonic
phase. However, some C2H2-type ZNFs, such as those with the Krüppel-associated
box (KRAB) domain, appeared relatively late in evolution and have significantly
increased family members in mammals including humans, possibly modulating their
complicated transcriptional network and/or supporting the morphological
development/functions specific to them. Such evolutional characteristics of the
C2H2-type ZNFs indicate that these molecules influence the NR functions
conserved through evolution, whereas some also adjust them to meet with specific
needs of higher organisms. We review the interaction between NRs and C2H2-type
ZNFs by focusing on some of the latter molecules.
Collapse
|
6
|
Kluska K, Adamczyk J, Krężel A. Metal binding properties, stability and reactivity of zinc fingers. Coord Chem Rev 2018. [DOI: 10.1016/j.ccr.2018.04.009] [Citation(s) in RCA: 109] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
7
|
Park SY, Kim YG. Rapid Assembly and Cloning of Zinc Finger Proteins with Multiple Finger Modules. B KOREAN CHEM SOC 2014. [DOI: 10.5012/bkcs.2014.35.7.2197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
8
|
Zhang Y, Yang H, Guo X, Rong N, Song Y, Xu Y, Lan W, Zhang X, Liu M, Xu Y, Cao C. The PHD1 finger of KDM5B recognizes unmodified H3K4 during the demethylation of histone H3K4me2/3 by KDM5B. Protein Cell 2014; 5:837-50. [PMID: 24952722 PMCID: PMC4225485 DOI: 10.1007/s13238-014-0078-4] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Accepted: 05/06/2014] [Indexed: 11/27/2022] Open
Abstract
KDM5B is a histone H3K4me2/3 demethylase. The PHD1 domain of KDM5B is critical for demethylation, but the mechanism underlying the action of this domain is unclear. In this paper, we observed that PHD1KDM5B interacts with unmethylated H3K4me0. Our NMR structure of PHD1KDM5B in complex with H3K4me0 revealed that the binding mode is slightly different from that of other reported PHD fingers. The disruption of this interaction by double mutations on the residues in the interface (L325A/D328A) decreases the H3K4me2/3 demethylation activity of KDM5B in cells by approximately 50% and increases the transcriptional repression of tumor suppressor genes by approximately twofold. These findings imply that PHD1KDM5B may help maintain KDM5B at target genes to mediate the demethylation activities of KDM5B.
Collapse
Affiliation(s)
- Yan Zhang
- State Key Laboratory of Bio-organic and Natural Product Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 200032 China
| | - Huirong Yang
- Institutes of Biomedical Sciences, Fudan University, 130 Dong-An Road, Shanghai, 200032 China
| | - Xue Guo
- Institutes of Biomedical Sciences, Fudan University, 130 Dong-An Road, Shanghai, 200032 China
| | - Naiyan Rong
- State Key Laboratory of Bio-organic and Natural Product Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 200032 China
| | - Yujiao Song
- State Key Laboratory of Bio-organic and Natural Product Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 200032 China
| | - Youwei Xu
- Institutes of Biomedical Sciences, Fudan University, 130 Dong-An Road, Shanghai, 200032 China
| | - Wenxian Lan
- State Key Laboratory of Bio-organic and Natural Product Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 200032 China
| | - Xu Zhang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071 China
| | - Maili Liu
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071 China
| | - Yanhui Xu
- Institutes of Biomedical Sciences, Fudan University, 130 Dong-An Road, Shanghai, 200032 China
| | - Chunyang Cao
- State Key Laboratory of Bio-organic and Natural Product Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 200032 China
| |
Collapse
|
9
|
Structural basis of pre-let-7 miRNA recognition by the zinc knuckles of pluripotency factor Lin28. Nat Struct Mol Biol 2011; 19:84-9. [PMID: 22157959 DOI: 10.1038/nsmb.2202] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Accepted: 11/10/2011] [Indexed: 12/11/2022]
Abstract
Lin28 inhibits the biogenesis of let-7 miRNAs through a direct interaction with the terminal loop of pre-let-7. This interaction requires the zinc-knuckle domains of Lin28. We show that the zinc knuckle domains of Lin28 are sufficient to provide binding selectivity for pre-let-7 miRNAs and present the NMR structure of human Lin28 zinc knuckles bound to the short sequence 5'-AGGAGAU-3'. The structure reveals that each zinc knuckle recognizes an AG dinucleotide separated by a single nucleotide spacer. This defines a new 5'-NGNNG-3' consensus motif that explains how Lin28 selectively recognizes pre-let-7 family members. Binding assays in cell lysates and functional assays in cultured cells demonstrate that the interactions observed in the solution structure also occur between the full-length protein and members of the pre-let-7 family. The consensus sequence explains several seemingly disparate previously published observations on the binding properties of Lin28.
Collapse
|
10
|
An extended dsRBD with a novel zinc-binding motif mediates nuclear retention of fission yeast Dicer. EMBO J 2011; 30:4223-35. [PMID: 21847092 PMCID: PMC3199388 DOI: 10.1038/emboj.2011.300] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2011] [Accepted: 07/22/2011] [Indexed: 01/06/2023] Open
Abstract
The Dicer ribonuclease Dcr1 plays an important role in the biogenesis of small regulatory RNAs. Surprisingly, RNA binding by the double-stranded RNA binding domain (dsRBD) is dispensable for Dcr1 function, while zinc coordination of the extended dsRBD is required for its nuclear localization and RNA silencing. Dicer proteins function in RNA interference (RNAi) pathways by generating small RNAs (sRNAs). Here, we report the solution structure of the C-terminal domain of Schizosaccharomyces pombe Dicer (Dcr1). The structure reveals an unusual double-stranded RNA binding domain (dsRBD) fold embedding a novel zinc-binding motif that is conserved among dicers in yeast. Although the C-terminal domain of Dcr1 still binds nucleic acids, this property is dispensable for proper functioning of Dcr1. In contrast, disruption of zinc coordination renders Dcr1 mainly cytoplasmic and leads to remarkable changes in gene expression and loss of heterochromatin assembly. In summary, our results reveal novel insights into the mechanism of nuclear retention of Dcr1 and raise the possibility that this new class of dsRBDs might generally function in nucleocytoplasmic trafficking and not substrate binding. The C-terminal domain of Dcr1 constitutes a novel regulatory module that might represent a potential target for therapeutic intervention with fungal diseases.
Collapse
|
11
|
Machida S, Chen HY, Adam Yuan Y. Molecular insights into miRNA processing by Arabidopsis thaliana SERRATE. Nucleic Acids Res 2011; 39:7828-36. [PMID: 21685453 PMCID: PMC3177193 DOI: 10.1093/nar/gkr428] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In plant, primary transcripts (pri-miRNAs) transcribed from miRNA genes by RNA polymerase II are first processed into stem-loop pre-miRNAs and further chopped into ∼21 nt long miRNAs by RNase III-like enzyme DCL1. SERRATE (SE) protein is an essential component for miRNA processing by assisting DCL1 for accurate cleavage. Here we report the crystal structure of Arabidopsis SE core (residues 194-543) at 2.7 Å. SE core adopts the 'walking man-like' topology with N-terminal α helices, C-terminal non-canonical zinc-finger domain and novel Middle domain resembling the leading leg, the lagging leg and the body, respectively. Pull-down assay shows that SE core provides the platform for HYL1 and DCL1 binding, whereas in vitro RNA binding and in vivo mutant rescue experiments suggest that the non-canonical zinc-finger domain coupled with C-terminal tail binds miRNA precursors. SE presumably works as a scaffold-like protein capable of binding both protein and RNA to guide the positioning of miRNA precursor toward DCL1 catalytic site within miRNA processing machinery in plant.
Collapse
Affiliation(s)
- Satoru Machida
- Department of Biological Sciences, National University of Singapore, Singapore
| | | | | |
Collapse
|
12
|
Klug A. The discovery of zinc fingers and their applications in gene regulation and genome manipulation. Annu Rev Biochem 2010; 79:213-31. [PMID: 20192761 DOI: 10.1146/annurev-biochem-010909-095056] [Citation(s) in RCA: 490] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
An account is given of the discovery of the classical Cys(2)His(2) zinc finger, arising from the interpretation of biochemical studies on the interaction of the Xenopus protein transcription factor IIIA with 5S RNA, and of structural studies on its structure and its interaction with DNA. The finger is a self-contained domain stabilized by a zinc ion ligated to a pair of cysteines and a pair of histidines, and by an inner hydrophobic core. This discovery showed not only a new protein fold but also a novel principle of DNA recognition. Whereas other DNA binding proteins generally make use of the two-fold symmetry of the double helix, zinc fingers can be linked linearly in tandem to recognize nucleic acid sequences of varying lengths. This modular design offers a large number of combinatorial possibilities for the specific recognition of DNA (or RNA). It is therefore not surprising that the zinc finger is found widespread in nature, including 3% of the genes of the human genome. The zinc finger design is ideally suited for engineering proteins to target specific genes. In the first example of their application in 1994, a three-finger protein was constructed to block the expression of an oncogene transformed into a mouse cell line. In addition, a reporter gene was activated by targeting an inserted zinc finger promoter. Thus, by fusing zinc finger peptides to repression or activation domains, genes can be selectively switched off or on. It was also suggested that by combining zinc fingers with other effector domains, e.g., from nucleases or integrases, to form chimeric proteins, genomes could be manipulated or modified. Several applications of such engineered zinc finger proteins are described here, including some of therapeutic importance.
Collapse
Affiliation(s)
- Aaron Klug
- MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, United Kingdom.
| |
Collapse
|
13
|
The discovery of zinc fingers and their development for practical applications in gene regulation and genome manipulation. Q Rev Biophys 2010; 43:1-21. [DOI: 10.1017/s0033583510000089] [Citation(s) in RCA: 168] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
AbstractA long-standing goal of molecular biologists has been to construct DNA-binding proteins for the control of gene expression. The classical Cys2His2 (C2H2) zinc finger design is ideally suited for such purposes. Discriminating between closely related DNA sequences both in vitro and in vivo, this naturally occurring design was adopted for engineering zinc finger proteins (ZFPs) to target genes specifically.Zinc fingers were discovered in 1985, arising from the interpretation of our biochemical studies on the interaction of the Xenopus protein transcription factor IIIA (TFIIIA) with 5S RNA. Subsequent structural studies revealed its three-dimensional structure and its interaction with DNA. Each finger constitutes a self-contained domain stabilized by a zinc (Zn) ion ligated to a pair of cysteines and a pair of histidines and also by an inner structural hydrophobic core. This discovery showed not only a new protein fold but also a novel principle of DNA recognition. Whereas other DNA-binding proteins generally make use of the 2-fold symmetry of the double helix, functioning as homo- or heterodimers, zinc fingers can be linked linearly in tandem to recognize nucleic acid sequences of varying lengths. This modular design offers a large number of combinatorial possibilities for the specific recognition of DNA (or RNA). It is therefore not surprising that the zinc finger is found widespread in nature, including 3% of the genes of the human genome.The zinc finger design can be used to construct DNA-binding proteins for specific intervention in gene expression. By fusing selected zinc finger peptides to repression or activation domains, genes can be selectively switched off or on by targeting the peptide to the desired gene target. It was also suggested that by combining an appropriate zinc finger peptide with other effector or functional domains, e.g. from nucleases or integrases to form chimaeric proteins, genomes could be modified or manipulated.The first example of the power of the method was published in 1994 when a three-finger protein was constructed to block the expression of a human oncogene transformed into a mouse cell line. The same paper also described how a reporter gene was activated by targeting an inserted 9-base pair (bp) sequence, which acts as the promoter. Thus, by fusing zinc finger peptides to repression or activation domains, genes can be selectively switched off or on. It was also suggested that, by combining zinc fingers with other effector or functional domains, e.g. from nucleases or integrases, to form chimaeric proteins, genomes could be manipulated or modified.Several applications of such engineered ZFPs are described here, including some of therapeutic importance, and also their adaptation for breeding improved crop plants.
Collapse
|
14
|
Gamsjaeger R, Swanton MK, Kobus FJ, Lehtomaki E, Lowry JA, Kwan AH, Matthews JM, Mackay JP. Structural and biophysical analysis of the DNA binding properties of myelin transcription factor 1. J Biol Chem 2007; 283:5158-67. [PMID: 18073212 DOI: 10.1074/jbc.m703772200] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Zinc binding domains, or zinc fingers (ZnFs), form one of the most numerous and most diverse superclasses of protein structural motifs in eukaryotes. Although our understanding of the functions of several classes of these domains is relatively well developed, we know much less about the molecular mechanisms of action of many others. Myelin transcription factor 1 (MyT1) type ZnFs are found in organisms as diverse as nematodes and mammals and are found in a range of sequence contexts. MyT1, one of the early transcription factors expressed in the developing central nervous system, contains seven MyT1 ZnFs that are very highly conserved both within the protein and between species. We have used a range of biophysical techniques, including NMR spectroscopy and data-driven macromolecular docking, to investigate the structural basis for the interaction between MyT1 ZnFs and DNA. Our data indicate that MyT1 ZnFs recognize the major groove of DNA in a way that appears to differ from other known zinc binding domains.
Collapse
Affiliation(s)
- Roland Gamsjaeger
- School of Molecular and Microbial Biosciences, University of Sydney, Building G08, New South Wales, Sydney 2006, Australia
| | | | | | | | | | | | | | | |
Collapse
|
15
|
Beasley SA, Hristova VA, Shaw GS. Structure of the Parkin in-between-ring domain provides insights for E3-ligase dysfunction in autosomal recessive Parkinson's disease. Proc Natl Acad Sci U S A 2007; 104:3095-100. [PMID: 17360614 PMCID: PMC1805599 DOI: 10.1073/pnas.0610548104] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Mutations in Parkin are one of the predominant hereditary factors found in patients suffering from autosomal recessive juvenile Parkinsonism. Parkin is a member of the E3 ubiquitin ligase family that is defined by a tripartite RING1-in-between-ring (IBR)-RING2 motif. In Parkin, the IBR domain has been shown to augment binding of the E2 proteins UbcH7 and UbcH8, and the subsequent ubiquitination of the proteins synphilin-1, Sept5, and SIM2. To facilitate our understanding of Parkin function, the solution structure of the Parkin IBR domain was solved by using NMR spectroscopy. Folding of the IBR domain (residues M327-S378) was found to be zinc dependent, and the structure reveals the domain forms a unique pair scissor-like and GAG knuckle-like zinc-binding sites, different from other zinc-binding motifs such as the RING, LIM, PHD, or B-box motifs. The N terminus of the IBR domain, residues E307-E322, is unstructured. The disease causing mutation T351P causes global unfolding, whereas the mutation R334C causes some structural rearrangement of the domain. In contrast, the protein containing the mutation G328E appears to be properly folded. The structure of the Parkin IBR domain, in combination with mutational data, allows a model to be proposed where the IBR domain facilitates a close arrangement of the adjacent RING1 and RING2 domains to facilitate protein interactions and subsequent ubiquitination.
Collapse
Affiliation(s)
- Steven A. Beasley
- Department of Biochemistry, University of Western Ontario, London, ON, Canada N6A 5C1
| | | | - Gary S. Shaw
- Department of Biochemistry, University of Western Ontario, London, ON, Canada N6A 5C1
- *To whom correspondence should be addressed. E-mail:
| |
Collapse
|
16
|
Papworth M, Kolasinska P, Minczuk M. Designer zinc-finger proteins and their applications. Gene 2006; 366:27-38. [PMID: 16298089 DOI: 10.1016/j.gene.2005.09.011] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2005] [Accepted: 09/18/2005] [Indexed: 10/25/2022]
Abstract
The Cys(2)His(2) zinc finger is one of the most common DNA-binding motifs in Eukaryota. A simple mode of DNA recognition by the Cys(2)His(2) zinc finger domain provides an ideal scaffold for designing proteins with novel sequence specificities. The ability to bind specifically to virtually any DNA sequence combined with the potential of fusing them with effector domains has led to the technology of engineering of chimeric DNA-modifying enzymes and transcription factors. This in turn has opened the possibility of using the engineered zinc finger-based factors as novel human therapeutics. One such synthetic factor-designer zinc finger transcription activator of the vascular endothelial growth factor A gene-has recently entered clinical trials to evaluate the ability of stimulating the growth of blood vessels in treating the peripheral arterial obstructive disease. This review concentrates on the aspects of natural Cys(2)His(2) zinc fingers evolution and fundamental steps in design of engineered zinc finger proteins. The applications of engineered zinc finger proteins are discussed in a context of the mechanism mediating their effect on the targeted DNA. Furthermore, the regulation of the expression of zinc finger proteins and their targeting to various cellular compartments and to chromatin and non-chromatin target templates are described. Also possible future applications of designer zinc finger proteins are discussed.
Collapse
Affiliation(s)
- Monika Papworth
- MRC Laboratory of Molecular Biology, Hills Road, CB2 2QH, UK.
| | | | | |
Collapse
|
17
|
Oakhill JS, Sutton BJ, Gorringe AR, Evans RW. Homology modelling of transferrin-binding protein A from Neisseria meningitidis. Protein Eng Des Sel 2005; 18:221-8. [PMID: 15820975 DOI: 10.1093/protein/gzi024] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Neisseria meningitidis, a causative agent of bacterial meningitis, obtains transferrin-bound iron by expressing two outer membrane located transferrin-binding proteins, TbpA and TbpB. TbpA is thought to be an integral outer membrane pore that facilitates iron uptake. Evidence suggests that TbpA is a useful antigen for inclusion in a vaccine effective against meningococcal disease, hence the identification of regions involved in ligand binding is of paramount importance to design strategies to block uptake of iron. The protein shares sequence and functional similarities to the Escherichia coli siderophore receptors FepA and FhuA, whose structures have been determined. These receptors are composed of two domains, a 22-stranded beta-barrel and an N-terminal plug region that sits within the barrel and occludes the transmembrane pore. A three-dimensional TbpA model was constructed using FepA and FhuA structural templates, hydrophobicity analysis and homology modelling. TbpA was found to possess a similar architecture to the siderophore receptors. In addition to providing insights into the highly immunogenic nature of TbpA and allowing the prediction of potentially important ligand-binding epitopes, the model also reveals a narrow channel through its entire length. The relevance of this channel and the spatial arrangement of external loops, to the mechanism of iron translocation employed by TbpA is discussed.
Collapse
Affiliation(s)
- Jonathan S Oakhill
- Metalloprotein Research Group, Randall Division of Cell and Molecular Biophysics, King's College London, New Hunt's House, Guy's Campus, London SE1 1UL, UK
| | | | | | | |
Collapse
|
18
|
Gutiérrez P, Osborne MJ, Siddiqui N, Trempe JF, Arrowsmith C, Gehring K. Structure of the archaeal translation initiation factor aIF2 beta from Methanobacterium thermoautotrophicum: implications for translation initiation. Protein Sci 2004; 13:659-67. [PMID: 14978306 PMCID: PMC2286745 DOI: 10.1110/ps.03506604] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
aIF2 beta is the archaeal homolog of eIF2 beta, a member of the eIF2 heterotrimeric complex, implicated in the delivery of Met-tRNA(i)(Met) to the 40S ribosomal subunit. We have determined the solution structure of the intact beta-subunit of aIF2 from Methanobacterium thermoautotrophicum. aIF2 beta is composed of an unfolded N terminus, a mixed alpha/beta core domain and a C-terminal zinc finger. NMR data shows the two folded domains display restricted mobility with respect to each other. Analysis of the aIF2 gamma structure docked to tRNA allowed the identification of a putative binding site for the beta-subunit in the ternary translation complex. Based on structural similarity and biochemical data, a role for the different secondary structure elements is suggested.
Collapse
MESH Headings
- Amino Acid Sequence
- Archaeal Proteins/chemistry
- Archaeal Proteins/genetics
- Archaeal Proteins/metabolism
- Binding Sites/genetics
- Cloning, Molecular
- Databases, Protein
- Guanosine Triphosphate/chemistry
- Guanosine Triphosphate/metabolism
- Methanobacterium/chemistry
- Methanobacterium/genetics
- Models, Molecular
- Molecular Sequence Data
- Nuclear Magnetic Resonance, Biomolecular
- Peptide Chain Initiation, Translational
- Peptide Initiation Factors/chemistry
- Peptide Initiation Factors/genetics
- Peptide Initiation Factors/metabolism
- Protein Binding
- Protein Conformation
- Protein Structure, Secondary
- RNA, Transfer, Met/chemistry
- RNA, Transfer, Met/metabolism
- Recombinant Proteins/chemistry
- Sequence Homology, Amino Acid
- Static Electricity
- Structural Homology, Protein
- Zinc Fingers/genetics
Collapse
Affiliation(s)
- Pablo Gutiérrez
- McGill University, Department of Biochemistry, McIntyre Medical Science Building, 3655 Promenade Sir William Osler, Montréal, Québec H3G 1Y6, Canada
| | | | | | | | | | | |
Collapse
|
19
|
Westman BJ, Perdomo J, Matthews JM, Crossley M, Mackay JP. Structural Studies on a Protein-Binding Zinc-Finger Domain of Eos Reveal Both Similarities and Differences to Classical Zinc Fingers†. Biochemistry 2004; 43:13318-27. [PMID: 15491138 DOI: 10.1021/bi049506a] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The oligomerization domain that is present at the C terminus of Ikaros-family proteins and the protein Trps-1 is important for the proper regulation of developmental processes such as hematopoiesis. Remarkably, this domain is predicted to contain two classical zinc fingers (ZnFs), domains normally associated with the recognition of nucleic acids. The preference for protein binding by these predicted ZnFs is not well-understood. We have used a range of methods to gain insight into the structure of this domain. Circular dichroism, UV-vis, and NMR experiments carried out on the C-terminal domain of Eos (EosC) revealed that the two putative ZnFs (C1 and C2) are separable, i.e., capable of folding independently in the presence of Zn(II). We next determined the structure of EosC2 using NMR spectroscopy, revealing that, although the overall fold of EosC2 is similar to other classical ZnFs, a number of differences exist. For example, the conformation of the C terminus of EosC2 appears to be flexible and may result in a major rearrangement of the zinc ligands. Finally, alanine-scanning mutagenesis was used to identify the residues that are involved in the homo- and hetero-oligomerization of Eos, and these results are discussed in the context of the structure of EosC. These studies provide the first structural insights into how EosC mediates protein-protein interactions and contributes to our understanding of why it does not exhibit high-affinity DNA binding.
Collapse
Affiliation(s)
- Belinda J Westman
- School of Molecular and Microbial Biosciences, University of Sydney, Sydney, New South Wales 2006, Australia
| | | | | | | | | |
Collapse
|
20
|
Simpson RJY, Yi Lee SH, Bartle N, Sum EY, Visvader JE, Matthews JM, Mackay JP, Crossley M. A Classic Zinc Finger from Friend of GATA Mediates an Interaction with the Coiled-coil of Transforming Acidic Coiled-coil 3. J Biol Chem 2004; 279:39789-97. [PMID: 15234987 DOI: 10.1074/jbc.m404130200] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Classic zinc finger domains (cZFs) consist of a beta-hairpin followed by an alpha-helix. They are among the most abundant of all protein domains and are often found in tandem arrays in DNA-binding proteins, with each finger contributing an alpha-helix to effect sequence-specific DNA recognition. Lone cZFs, not found in tandem arrays, have been postulated to function in protein interactions. We have studied the transcriptional co-regulator Friend of GATA (FOG), which contains nine zinc fingers. We have discovered that the third cZF of FOG contacts a coiled-coil domain in the centrosomal protein transforming acidic coiled-coil 3 (TACC3). Although FOG-ZF3 exhibited low solubility, we have used a combination of mutational mapping and protein engineering to generate a derivative that was suitable for in vitro and structural analysis. We report that the alpha-helix of FOG-ZF3 recognizes a C-terminal portion of the TACC3 coiled-coil. Remarkably, the alpha-helical surface utilized by FOG-ZF3 is the same surface responsible for the well established sequence-specific DNA-binding properties of many other cZFs. Our data demonstrate the versatility of cZFs and have implications for the analysis of many as yet uncharacterized cZF proteins.
Collapse
Affiliation(s)
- Raina J Y Simpson
- School of Molecular and Microbial Biosciences, G08, University of Sydney, NSW 2006, Australia
| | | | | | | | | | | | | | | |
Collapse
|
21
|
Capili AD, Edghill EL, Wu K, Borden KLB. Structure of the C-terminal RING finger from a RING-IBR-RING/TRIAD motif reveals a novel zinc-binding domain distinct from a RING. J Mol Biol 2004; 340:1117-29. [PMID: 15236971 DOI: 10.1016/j.jmb.2004.05.035] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2004] [Revised: 05/27/2004] [Accepted: 05/27/2004] [Indexed: 11/25/2022]
Abstract
The really interesting new gene (RING) family of proteins contains over 400 members with diverse physiological functions. A subset of these domains is found in the context of the RING-IBR-RING/TRIAD motifs which function as E3 ubiquitin ligases. Our sequence analysis of the C-terminal RING (RING2) from this motif show that several metal ligating and hydrophobic residues critical for the formation of a classical RING cross-brace structure are not present. Thus, we determined the structure of the RING2 from the RING-IBR-RING motif of HHARI and showed that RING2 has a completely distinct topology from classical RINGs. Notably, RING2 binds only one zinc atom per monomer rather than two and uses a different hydrophobic network to that of classical RINGs. Additionally, this RING2 topology is novel, bearing slight resemblance to zinc-ribbon motifs around the zinc site and is different from the topologies of the zinc binding sites found in RING and PHDs. We demonstrate that RING2 acts as an E3 ligase in vitro and using mutational analysis deduce the structural features required for this activity. Further, mutations in the RING-IBR-RING of Parkin cause a rare form of Parkinsonism and these studies provide an explanation for those mutations that occur in its RING2. From a comparison of the RING2 structure with those reported for RINGs, we infer sequence determinants that allow discrimination between RING2 and RING domains at the sequence analysis level.
Collapse
Affiliation(s)
- Allan D Capili
- Structural Biology Program, Department of Physiology and Biophysics, Mount Sinai School of Medicine, New York University, New York, NY 10029, USA
| | | | | | | |
Collapse
|
22
|
Simpson RJY, Cram ED, Czolij R, Matthews JM, Crossley M, Mackay JP. CCHX zinc finger derivatives retain the ability to bind Zn(II) and mediate protein-DNA interactions. J Biol Chem 2003; 278:28011-8. [PMID: 12736264 DOI: 10.1074/jbc.m211146200] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Classical (CCHH) zinc fingers are among the most common protein domains found in eukaryotes. They function as molecular recognition elements that mediate specific contact with DNA, RNA, or other proteins and are composed of a betabetaalpha fold surrounding a single zinc ion that is ligated by two cysteine and two histidine residues. In a number of variant zinc fingers, the final histidine is not conserved, and in other unrelated zinc binding domains, residues such as aspartate can function as zinc ligands. To test whether the final histidine is required for normal folding and the DNA-binding function of classical zinc fingers, we focused on finger 3 of basic Krüppel-like factor. The structure of this domain was determined using NMR spectroscopy and found to constitute a typical classical zinc finger. We generated a panel of substitution mutants at the final histidine in this finger and found that several of the mutants retained some ability to fold in the presence of zinc. Consistent with this result, we showed that mutation of the final histidine had only a modest effect on DNA binding in the context of the full three-finger DNA-binding domain of basic Krüppel-like factor. Further, the zinc binding ability of one of the point mutants was tested and found to be indistinguishable from the wild-type domain. These results suggest that the final zinc chelating histidine is not an essential feature of classical zinc fingers and have implications for zinc finger evolution, regulation, and the design of experiments testing the functional roles of these domains.
Collapse
Affiliation(s)
- Raina J Y Simpson
- School of Molecular and Microbial Biosciences, G08, University of Sydney, New South Wales 2006, Australia
| | | | | | | | | | | |
Collapse
|
23
|
Kwan AHY, Gell DA, Verger A, Crossley M, Matthews JM, Mackay JP. Engineering a protein scaffold from a PHD finger. Structure 2003; 11:803-13. [PMID: 12842043 DOI: 10.1016/s0969-2126(03)00122-9] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The design of proteins with tailored functions remains a relatively elusive goal. Small size, a well-defined structure, and the ability to maintain structural integrity despite multiple mutations are all desirable properties for such designer proteins. Many zinc binding domains fit this description. We determined the structure of a PHD finger from the transcriptional cofactor Mi2beta and investigated the suitability of this domain as a scaffold for presenting selected binding functions. The two flexible loops in the structure were mutated extensively by either substitution or expansion, without affecting the overall fold of the domain. A binding site for the corepressor CtBP2 was also grafted onto the domain, creating a new PHD domain that can specifically bind CtBP2 both in vitro and in the context of a eukaryotic cell nucleus. These results represent a step toward designing new regulatory proteins for modulating aberrant gene expression in vivo.
Collapse
Affiliation(s)
- Ann H Y Kwan
- School of Molecular and Microbial Biosciences, University of Sydney, Sydney, New South Wales 2006 Australia
| | | | | | | | | | | |
Collapse
|
24
|
Schaufler LE, Klevit RE. Mechanism of DNA binding by the ADR1 zinc finger transcription factor as determined by SPR. J Mol Biol 2003; 329:931-9. [PMID: 12798683 DOI: 10.1016/s0022-2836(03)00550-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The ADR1 protein recognizes a six base-pair consensus DNA sequence using two zinc fingers and an adjacent accessory motif. Kinetic measurements were performed on the DNA-binding domain of ADR1 using surface plasmon resonance. Binding by ADR1 was characterized to two known native binding sequences from the ADH2 and CTA1 promoter regions, which differ in two of the six consensus positions. In addition, non-specific binding by ADR1 to a random DNA sequence was measured. ADR1 binds the native sites with nanomolar affinities. Remarkably, ADR1 binds non-specific DNA with affinities only approximately tenfold lower than the native sequences. The specific and non-specific binding affinities are conferred mainly by differences in the association phase of DNA binding. The association rate for the complex is strongly influenced by the proximal accessory region, while the dissociation reaction and specificity of binding are controlled by the two zinc fingers. Binding kinetics of two ADR1 mutants was also examined. ADR1 containing an R91K mutation in the accessory region bound with similar affinity to wild-type, but with slightly less sequence specificity. The R91K mutation was observed to increase binding affinity to a suboptimal sequence by decreasing the complex dissociation rate. L146H, a change-of-specificity mutation at the +3 position of the second zinc finger, bound its preferred sequence with a slightly higher affinity than wild-type. The L146H mutant indicates that beneficial protein-DNA contacts provide similar levels of stabilization to the complex, whether they are hydrogen-bonding or van der Waals interactions.
Collapse
Affiliation(s)
- Lawrence E Schaufler
- Molecular and Cellular Biology Program, University of Washington, Seattle, WA 98195, USA
| | | |
Collapse
|
25
|
Plambeck CA, Kwan AHY, Adams DJ, Westman BJ, van der Weyden L, Medcalf RL, Morris BJ, Mackay JP. The structure of the zinc finger domain from human splicing factor ZNF265 fold. J Biol Chem 2003; 278:22805-11. [PMID: 12657633 DOI: 10.1074/jbc.m301896200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Identification of the protein domains that are responsible for RNA recognition has lagged behind the characterization of protein-DNA interactions. However, it is now becoming clear that a range of structural motifs bind to RNA and their structures and molecular mechanisms of action are beginning to be elucidated. In this report, we have expressed and purified one of the two putative RNA-binding domains from ZNF265, a protein that has been shown to bind to the spliceosomal components U1-70K and U2AF35 and to direct alternative splicing. We show that this domain, which contains four highly conserved cysteine residues, forms a stable, monomeric structure upon the addition of 1 molar eq of Zn(II). Determination of the solution structure of this domain reveals a conformation comprising two stacked beta-hairpins oriented at approximately 80 degrees to each other and sandwiching the zinc ion; the fold resembles the zinc ribbon class of zinc-binding domains, although with one less beta-strand than most members of the class. Analysis of the structure reveals a striking resemblance to known RNA-binding motifs in terms of the distribution of key surface residues responsible for making RNA contacts, despite a complete lack of structural homology. Furthermore, we have used an RNA gel shift assay to demonstrate that a single crossed finger domain from ZNF265 is capable of binding to an RNA message. Taken together, these results define a new RNA-binding motif and should provide insight into the functions of the >100 uncharacterized proteins in the sequence data bases that contain this domain.
Collapse
Affiliation(s)
- Craig A Plambeck
- Basic and Clinical Genomics Laboratory, School of Medical Science, University of Sydney, New South Wales 2006, Australia
| | | | | | | | | | | | | | | |
Collapse
|
26
|
Kwon K, Cao C, Stivers JT. A novel zinc snap motif conveys structural stability to 3-methyladenine DNA glycosylase I. J Biol Chem 2003; 278:19442-6. [PMID: 12654914 DOI: 10.1074/jbc.m300934200] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Escherichia coli 3-methyladenine DNA glycosylase I (TAG) is a DNA repair enzyme that excises 3-methyladenine in DNA and is the smallest member of the helix-hairpin-helix (HhH) superfamily of DNA glycosylases. Despite many studies over the last 25 years, there has been no suggestion that TAG was a metalloprotein. However, here we establish by heteronuclear NMR and other spectroscopic methods that TAG binds 1 eq of Zn2+ extremely tightly. A family of refined NMR structures shows that 4 conserved residues contributed from the amino- and carboxyl-terminal regions of TAG (Cys4, His17, His175, and Cys179) form a Zn2+ binding site. The Zn2+ ion serves to tether the otherwise unstructured amino- and carboxyl-terminal regions of TAG. We propose that this unexpected "zinc snap" motif in the TAG family (CX(12-17)HX(approximately 150)HX(3)C) serves to stabilize the HhH domain thereby mimicking the functional role of protein-protein interactions in larger HhH superfamily members.
Collapse
Affiliation(s)
- Keehwan Kwon
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205-2185, USA
| | | | | |
Collapse
|
27
|
Paulino M, Esperón P, Vega M, Scazzocchio C, Tapia O. Modelling CreA protein–DNA recognition determinants. A molecular dynamics study of fully charged CreA–DNA model in water. ACTA ACUST UNITED AC 2002. [DOI: 10.1016/s0166-1280(01)00619-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
28
|
Hanzawa H, de Ruwe MJ, Albert TK, van Der Vliet PC, Timmers HT, Boelens R. The structure of the C4C4 ring finger of human NOT4 reveals features distinct from those of C3HC4 RING fingers. J Biol Chem 2001; 276:10185-90. [PMID: 11087754 DOI: 10.1074/jbc.m009298200] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The NOT4 protein is a component of the CCR4.NOT complex, a global regulator of RNA polymerase II transcription. Human NOT4 (hNOT4) contains a RING finger motif of the C(4)C(4) type. We expressed and purified the N-terminal region of hNOT4 (residues 1-78) encompassing the RING finger motif and determined the solution structure by heteronuclear NMR. NMR experiments using a (113)Cd-substituted hNOT4 RING finger showed that two metal ions are bound through cysteine residues in a cross-brace manner. The three-dimensional structure of the hNOT4 RING finger was refined with root mean square deviation values of 0.58 +/- 0.13 A for the backbone atoms and 1.08 +/- 0.12 A for heavy atoms. The hNOT4 RING finger consists of an alpha-helix and three long loops that are stabilized by zinc coordination. The overall folding of the hNOT4 RING finger is similar to that of the C(3)HC(4) RING fingers. The relative orientation of the two zinc-chelating loops and the alpha-helix is well conserved. However, for the other regions, the secondary structural elements are distinct.
Collapse
Affiliation(s)
- H Hanzawa
- Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | | | | | | | | | | |
Collapse
|
29
|
Wolfe SA, Nekludova L, Pabo CO. DNA recognition by Cys2His2 zinc finger proteins. ANNUAL REVIEW OF BIOPHYSICS AND BIOMOLECULAR STRUCTURE 2001; 29:183-212. [PMID: 10940247 DOI: 10.1146/annurev.biophys.29.1.183] [Citation(s) in RCA: 732] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Cys2His2 zinc fingers are one of the most common DNA-binding motifs found in eukaryotic transcription factors. These proteins typically contain several fingers that make tandem contacts along the DNA. Each finger has a conserved beta beta alpha structure, and amino acids on the surface of the alpha-helix contact bases in the major groove. This simple, modular structure of zinc finger proteins, and the wide variety of DNA sequences they can recognize, make them an attractive framework for attempts to design novel DNA-binding proteins. Several studies have selected fingers with new specificities, and there clearly are recurring patterns in the observed side chain-base interactions. However, the structural details of recognition are intricate enough that there are no general rules (a "recognition code") that would allow the design of an optimal protein for any desired target site. Construction of multifinger proteins is also complicated by interactions between neighboring fingers and the effect of the intervening linker. This review analyzes DNA recognition by Cys2His2 zinc fingers and summarizes progress in generating proteins with novel specificities from fingers selected by phage display.
Collapse
Affiliation(s)
- S A Wolfe
- Howard Hughes Medical Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge 02139, USA
| | | | | |
Collapse
|
30
|
Laity JH, Lee BM, Wright PE. Zinc finger proteins: new insights into structural and functional diversity. Curr Opin Struct Biol 2001; 11:39-46. [PMID: 11179890 DOI: 10.1016/s0959-440x(00)00167-6] [Citation(s) in RCA: 1021] [Impact Index Per Article: 44.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Zinc finger proteins are among the most abundant proteins in eukaryotic genomes. Their functions are extraordinarily diverse and include DNA recognition, RNA packaging, transcriptional activation, regulation of apoptosis, protein folding and assembly, and lipid binding. Zinc finger structures are as diverse as their functions. Structures have recently been reported for many new zinc finger domains with novel topologies, providing important insights into structure/function relationships. In addition, new structural studies of proteins containing the classical Cys(2)His(2) zinc finger motif have led to novel insights into mechanisms of DNA binding and to a better understanding of their broader functions in transcriptional regulation.
Collapse
Affiliation(s)
- J H Laity
- Department of Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | | | | |
Collapse
|
31
|
Capili AD, Schultz DC, Rauscher FJ, Borden KL. Solution structure of the PHD domain from the KAP-1 corepressor: structural determinants for PHD, RING and LIM zinc-binding domains. EMBO J 2001; 20:165-77. [PMID: 11226167 PMCID: PMC140198 DOI: 10.1093/emboj/20.1.165] [Citation(s) in RCA: 142] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Plant homeodomain (PHD) domains are found in >400 eukaryotic proteins, many of which are transcriptional regulators. Naturally occurring point mutations or deletions of this domain contribute to a variety of human diseases, including ATRX syndrome, myeloid leukemias and autoimmune dysfunction. Here we report the first structural characterization of a PHD domain. Our studies reveal that the PHD domain from KAP-1 corepressor binds zinc in a cross-brace topology between anti-parallel ss-strands reminiscent of RING (really interesting new gene) domains. Using a mutational analysis, we define the structural features required for transcriptional repression by KAP-1 and explain naturally occurring, disease-causing mutations in PHD domains of other proteins. From a comparison of this PHD structure with previously reported RING and LIM (Lin11/Isl-1/Mec-3) structures, we infer sequence determinants that allow discrimination among PHD, RING and LIM motifs.
Collapse
Affiliation(s)
| | - David C. Schultz
- Structural Biology Program, Department of Physiology and Biophysics, Mount Sinai School of Medicine, New York University, New York, NY 10029 and
The Wistar Institute, 3601 Spruce Street, Philadelphia, PA 19104, USA Corresponding authors e-mail: or A.D.Capili and D.C.Schultz contributed equally to this work
| | - Frank J. Rauscher
- Structural Biology Program, Department of Physiology and Biophysics, Mount Sinai School of Medicine, New York University, New York, NY 10029 and
The Wistar Institute, 3601 Spruce Street, Philadelphia, PA 19104, USA Corresponding authors e-mail: or A.D.Capili and D.C.Schultz contributed equally to this work
| | - Katherine L.B. Borden
- Structural Biology Program, Department of Physiology and Biophysics, Mount Sinai School of Medicine, New York University, New York, NY 10029 and
The Wistar Institute, 3601 Spruce Street, Philadelphia, PA 19104, USA Corresponding authors e-mail: or A.D.Capili and D.C.Schultz contributed equally to this work
| |
Collapse
|
32
|
Manfield IW, Reynolds LA, Gittins J, Kneale GG. The DNA-binding domain of the gene regulatory protein AreA extends beyond the minimal zinc-finger region conserved between GATA proteins. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1493:325-32. [PMID: 11018257 DOI: 10.1016/s0167-4781(00)00197-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The AreA protein of Aspergillus nidulans regulates the activity of over 100 genes involved in the utilisation of nitrogen, and has a limited region of homology with the vertebrate family of GATA proteins around a zinc finger (Zf) motif. A 66 amino acid (a.a.) residue fragment (Zf(66)) corresponding to the zinc finger, a 91 a.a fragment (Zf(91)) containing an additional 25 a.a. at the C-terminus, and a much larger 728 a.a. sequence (3'EX) corresponding to the 3'exon have been over-expressed as fusion proteins in E. coli and purified. The DNA-protein complexes formed by these proteins have been examined by gel retardation analysis. The 91 a.a. protein forms a discrete shifted species with a GATA-containing DNA fragment with high affinity (K(d)=0.15 nM), whereas the 66 a.a. protein has very low ( approximately microM) affinity for the same sequence. The results show that the region of AreA required for high affinity DNA binding extends beyond the zinc finger motif that is homologous to GATA-1, requiring in addition a region within the 25 a.a. sequence C-terminal to the zinc finger. Using hydroxyl radical and ethylation interference footprinting, the minimal Zinc finger protein (Zf(66)) shows no appreciable interference effects whereas Zf(91) shows much stronger interference effects, identical to those of the larger protein. These effects extend over sequences up to two nucleotides either side of the GATA site, and indicate contacts additional to those observed in the three-dimensional structure of the complex of the minimal zinc-finger protein with DNA. We suggest that these additional contacts are responsible for the enhanced DNA binding affinity of the extended zinc-finger protein Zf(91).
Collapse
Affiliation(s)
- I W Manfield
- Biophysics Laboratories, Institute of Biomedical and Biomolecular Sciences, University of Portsmouth, St. Michael's Building, PO1 2DT, Portsmouth, UK
| | | | | | | |
Collapse
|
33
|
Matthews JM, Kowalski K, Liew CK, Sharpe BK, Fox AH, Crossley M, MacKay JP. A class of zinc fingers involved in protein-protein interactions biophysical characterization of CCHC fingers from fog and U-shaped. EUROPEAN JOURNAL OF BIOCHEMISTRY 2000; 267:1030-8. [PMID: 10672011 DOI: 10.1046/j.1432-1327.2000.01095.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Zinc fingers (ZnFs) are extremely common protein domains. Several classes of ZnFs are distinguished by the nature and spacing of their zinc-coordinating residues. While the structure and function of some ZnFs are well characterized, many others have been identified only through their amino acid sequence. A number of proteins contain a conserved C-X2-C-X12-H-X1-5-C sequence, which is similar to the spacing observed for the 'classic' CCHH ZnFs. Although these domains have been implicated in protein-protein (and not protein-nucleic acid) interactions, nothing is known about their structure or function at a molecular level. Here, we address this problem through the expression and biophysical characterization of several CCHC-type zinc fingers from the erythroid transcription factor FOG and the related Drosophila protein U-shaped. Each of these domains does indeed fold in a zinc-dependent fashion, coordinating the metal in a tetrahedral manner through the sidechains of one histidine and three cysteine residues, and forming extremely thermostable structures. Analysis of CD spectra suggests an overall fold similar to that of the CCHH fingers, and indeed a point mutant of FOG-F1 in which the final cysteine residue is replaced by histidine remains capable of folding. However, the CCHC (as opposed to CCHH) motif is a prerequisite for GATA-1 binding activity, demonstrating that CCHC and CCHH topologies are not interchangeable. This demonstration that members of a structurally distinct subclass of genuine zinc finger domains are involved in the mediation of protein-protein interactions has implications for the prediction of protein function from nucleotide sequences.
Collapse
Affiliation(s)
- J M Matthews
- Department of Biochemistry, University of Sydney, NSW, Australia
| | | | | | | | | | | | | |
Collapse
|
34
|
Fletcher CM, Pestova TV, Hellen CU, Wagner G. Structure and interactions of the translation initiation factor eIF1. EMBO J 1999; 18:2631-7. [PMID: 10228174 PMCID: PMC1171342 DOI: 10.1093/emboj/18.9.2631] [Citation(s) in RCA: 122] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
eIF1 is a universally conserved translation factor that is necessary for scanning and involved in initiation site selection. We have determined the solution structure of human eIF1 with an N-terminal His tag using NMR spectroscopy. Residues 29-113 of the native sequence form a tightly packed domain with two alpha-helices on one side of a five-stranded parallel and antiparallel beta-sheet. The fold is new but similar to that of several ribosomal proteins and RNA-binding domains. A likely binding site is indicated by yeast mutations and conserved residues located together on the surface. No interaction with recombinant eIF5 or the initiation site RNA GCCACAAUGGCA was detected by NMR, but GST pull-down experiments show that eIF1 binds specifically to the p110 subunit of eIF3. This interaction explains how eIF1 is recruited to the 40S ribosomal subunit.
Collapse
Affiliation(s)
- C M Fletcher
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | | | | | | |
Collapse
|
35
|
Obata T, Yanagidani A, Yokoro K, Numoto M, Yamamoto S. Analysis of the consensus binding sequence and the DNA-binding domain of ZF5. Biochem Biophys Res Commun 1999; 255:528-34. [PMID: 10049742 DOI: 10.1006/bbrc.1998.9970] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Murine ZF5 is a transcription factor with five zinc finger motifs that represses the c-myc gene by binding to two GC-rich elements at the promoter region. Because of its ubiquitous expression in a variety of tissues, elucidation of biological functions and cellular target genes of ZF5 is of great interest. As the first step of identifying cellular target genes, we have attempted to determine the consensus binding motif for ZF5. We succeeded in isolating 19 oligonucleotide duplex DNAs to which ZF5 binds and determined the binding sequences with DNase I footprinting analysis. From these sequences, we deduced the consensus binding motif for ZF5 to be GSGCGCGR. In addition, we have analyzed the DNA-binding domain of ZF5 by testing a series of deletion mutants. It turned out that the zinc fingers 3 and 4 of the five finger motifs play a critical role in DNA binding.
Collapse
Affiliation(s)
- T Obata
- Department of Dermatology, Hiroshima University School of Medicine, Japan.
| | | | | | | | | |
Collapse
|
36
|
Haaf A, LeClaire L, Roberts G, Kent HM, Roberts TM, Stewart M, Neuhaus D. Solution structure of the motile major sperm protein (MSP) of Ascaris suum - evidence for two manganese binding sites and the possible role of divalent cations in filament formation. J Mol Biol 1998; 284:1611-24. [PMID: 9878374 DOI: 10.1006/jmbi.1998.2291] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The major sperm protein (MSP) of Ascaris suum mediates amoeboid motility by forming an extensive intermeshed system of cytoskeletal filaments analogous to that formed by actin in many other amoeboid cells. MSP is a dimeric molecule that polymerizes to form non-polar filaments constructed from two helical subfilaments that wind round one another. Moreover, MSP filaments can interact with one another to form higher-order assemblies without requiring the range of accessory proteins usually employed in actin-based systems. A knowledge of how MSP polymerizes and forms the hierarchical series of helical MSP macromolecular assemblies is fundamental to understanding locomotion in these cells. Here we describe the solution structure of MSP dimers determined by NMR spectroscopy under conditions where MSP does not polymerize to form filaments. The solution structure is indistinguishable from that observed in putative MSP subfilament helices by X-ray crystallography, indicating that MSP polymerization is not accompanied by a major conformational change. We also show that the rate of MSP polymerization associated with movement of vesicles in an in vitro motility assay is enhanced by the presence of magnesium and manganese ions and use NMR to show that the primary residues that bind these ions are 24-25 and 83-86. These residues are distant from the interface formed between MSP dimers in subfilament helices, and so are probably not involved in this level of polymerization. Instead the manganese and magnesium ion binding appears to be associated with the assembly of subfilaments into filaments and their subsequent aggregation into bundles.
Collapse
Affiliation(s)
- A Haaf
- MRC Laboratory of Molecular Biology, Hills Road, Cambridge, CB2 2QH, UK
| | | | | | | | | | | | | |
Collapse
|
37
|
Bhoite LT, Stillman DJ. Residues in the Swi5 zinc finger protein that mediate cooperative DNA binding with the Pho2 homeodomain protein. Mol Cell Biol 1998; 18:6436-46. [PMID: 9774660 PMCID: PMC109230 DOI: 10.1128/mcb.18.11.6436] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/1998] [Accepted: 08/20/1998] [Indexed: 11/20/2022] Open
Abstract
The Swi5 zinc finger and the Pho2 homeodomain DNA-binding proteins bind cooperatively to the HO promoter. Pho2 (also known as Bas2 or Grf10) activates transcription of diverse genes, acting with multiple distinct DNA-binding proteins. We have performed a genetic screen to identify amino acid residues in Swi5 that are required for synergistic transcriptional activation of a reporter construct in vivo. Nine unique amino acid substitutions within a 24-amino-acid region of Swi5, upstream of the DNA-binding domain, reduce expression of promoters that require both Swi5 and Pho2 for activation. In vitro DNA binding experiments show that the mutant Swi5 proteins bind DNA normally, but some mutant Swi5 proteins (resulting from SWI5* mutations) show reduced cooperative DNA binding with Pho2. In vivo experiments show that these SWI5* mutations sharply reduce expression of promoters that require both SWI5 and PHO2, while expression of promoters that require SWI5 but are PHO2 independent is largely unaffected. This suggests that these SWI5* mutations do not affect the ability of Swi5 to bind DNA or activate transcription but specifically affect the region of Swi5 required for interaction with Pho2. Two-hybrid experiments show that amino acids 471 to 513 of Swi5 are necessary and sufficient for interaction with Pho2 and that the SWI5* point mutations cause a severe reduction in this two-hybrid interaction. Analysis of promoter activation by these mutants suggests that this small region of Swi5 has at least two distinct functions, conferring specificity for activation of the HO promoter and for interaction with Pho2.
Collapse
Affiliation(s)
- L T Bhoite
- Division of Molecular Biology and Genetics, Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah 84132, USA
| | | |
Collapse
|
38
|
Muskett FW, Frenkiel TA, Feeney J, Freedman RB, Carr MD, Williamson RA. High resolution structure of the N-terminal domain of tissue inhibitor of metalloproteinases-2 and characterization of its interaction site with matrix metalloproteinase-3. J Biol Chem 1998; 273:21736-43. [PMID: 9705310 DOI: 10.1074/jbc.273.34.21736] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The high resolution structure of the N-terminal domain of tissue inhibitor of metalloproteinases-2 (N-TIMP-2) in solution has been determined using multidimensional heteronuclear NMR spectroscopy, with the structural calculations based on an extensive set of constraints, including 3132 nuclear Overhauser effect-based distance constraints, 56 hydrogen bond constraints, and 220 torsion angle constraints (an average of 26.9 constraints/residue). The core of the protein consists of a five-stranded beta-barrel that is homologous to the beta-barrel found in the oligosaccharide/oligonucleotide binding protein fold. The binding site for the catalytic domain of matrix metalloproteinases-3 (N-MMP-3) on N-TIMP-2 has been mapped by determining the changes in chemical shifts on complex formation for signals from the protein backbone (15N, 13C, and 1H). This approach identified a discrete N-MMP-3 binding site on N-TIMP-2 composed of the N terminus of the protein and the loops between beta-strands AB, CD, and EF. The beta-hairpin formed from strands A and B in N-TIMP-2 is significantly longer than the equivalent structure in TIMP-1, allowing it to make more extensive binding interactions with the MMP catalytic domain. A detailed comparison of the N-TIMP-2 structure with that of TIMP-1 bound to N-MMP-3 (Gomis-Ruth, F.-X., Maskos, K., Betz, M., Bergner, A., Huber, R., Suzuki, K., Yoshida, N., Nagase, H. , Brew, K., Bourne, G. P., Bartunik, H. & Bode, W. (1997) Nature 389, 77-80) revealed that the core beta-barrels are very similar in topology but that the loop connecting beta-strands CD (P67-C72) would need to undergo a large conformational change for TIMP-2 to bind in a similar manner to TIMP-1.
Collapse
Affiliation(s)
- F W Muskett
- Department of Biosciences, University of Kent, Canterbury, Kent, CT2 7NJ, United Kingdom
| | | | | | | | | | | |
Collapse
|
39
|
Chen X, Agarwal A, Giedroc DP. Structural and functional heterogeneity among the zinc fingers of human MRE-binding transcription factor-1. Biochemistry 1998; 37:11152-61. [PMID: 9698361 DOI: 10.1021/bi980843r] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
MRE-binding transcription factor-1 (MTF-1) activates the expression of metallothionein (MT) genes in mouse and human cells upon binding to one or more tandem metal-response elements (MREs; 5'-ctnTGCRCnCgGCCc) in the MT promoter. MTF-1 contains six Cys2-His2 zinc finger sequences. Previous work suggests that the zinc finger domain itself may function as a zinc sensor in zinc-activated expression of MTs. To obtain molecular insight into MTF-1 function, a recombinant fragment of MTF-1 containing only the zinc finger domain (denoted MTF-zf) has been purified using nondenaturing conditions and characterized with respect to zinc-binding properties, secondary structure, and DNA-binding activity. Different preparations of MTF-zf, following an anaerobic dialysis to quantify Zn(II) and reduced cysteine (by DTNB reactivity) content, reveal Zn(II)/MTF-zf stoichiometries ranging from 3.3 to 5.5 g at Zn(II) and 11-13 reduced thiolates (12 expected). Far-UV CD spectra reveal indistinguishable secondary structural content in all preparations, i.e., enough to fold just three of six zinc fingers of MTF-zf. Removal of additional zinc from MTF-zf gives rise to an insoluble apoprotein. Complex formation between a Zn5.5 MTF-zf and a coumarin-labeled MREd-containing oligonucleotide as monitored by changes in the anisotropy of the coumarin fluorescence gives a Kapp = 3.8 (+/-0.5) x 10(8) M-1 (pH 7.0, 0.20 M NaCl, 25 degreesC). Investigation of the salt type and concentration dependence of Kapp suggests significant contributions from both cation and anion release upon complex formation. Zn5.5 MTF-zf exhibits a large negative heat capacity of complex formation with MREd and can discriminate among DNA duplexes which have mutations deposited on either the TGCRC core or the C-rich side of the MREd. Air oxidation of Zn5.5 MTF-zf results in the reversible conversion of 6 of the 12 Cys thiolates to 3 disulfide bonds; as expected, this has no effect on the secondary structure of MTF-zf, but results in approximately 30-fold reduction in Kapp to approximately 1.2 x 10(7) M-1. In contrast, fully reduced Zn3.5 MTF-zf binds to the MREd with an affinity and [NaCl] dependence largely indistinguishable from those of Zn5.5 MTF-zf. The zinc fingers in MTF-zf are physically and functionally inequivalent. A subset (approximately 3-4) of zinc fingers plays a structural role in folding and high-affinity MREd binding, while one or more additional fingers have properties potentially consistent with a metalloregulatory role.
Collapse
Affiliation(s)
- X Chen
- Department of Biochemistry and Biophysics, Center for Macromolecular Design, Texas A&M University, College Station 77843-2128, USA
| | | | | |
Collapse
|
40
|
Viles JH, Patel SU, Mitchell JB, Moody CM, Justice DE, Uppenbrink J, Doyle PM, Harris CJ, Sadler PJ, Thornton JM. Design, synthesis and structure of a zinc finger with an artificial beta-turn. J Mol Biol 1998; 279:973-86. [PMID: 9642075 DOI: 10.1006/jmbi.1998.1764] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have incorporated a bicyclic beta-turn mimetic (BTD; beta-turn dipeptide) into a zinc finger, creating a zinc finger with an artificial beta-turn. The designed peptide chelates zinc and has the same fold as the unmodified native zinc finger (finger 3 of the human YY1 protein). A combination of 1H NMR and structure calculations reveals that, in solution, this zinc finger has a fold similar to the known wild-type crystal structure and to other zinc fingers containing the consensus sequence X3-Cys-X4-Cys-X12-His-X3-His-X. The peptide was designed with BTD between the chelating cysteine residues, with BTD forming a type II' beta-turn linking the two strands of a distorted anti-parallel beta-sheet. The C-terminal portion of the peptide forms a helix with zinc co-ordinating histidine residues on successive turns of the helix. This work represents a step towards developing methods by which parts of a target protein may be replaced by peptide mimetics.
Collapse
Affiliation(s)
- J H Viles
- Department of Chemistry, Birkbeck College, University of London, Gordon House, London, WC1H 0PP, UK
| | | | | | | | | | | | | | | | | | | |
Collapse
|
41
|
Nahon E, Raveh D. Targeting a truncated Ho-endonuclease of yeast to novel DNA sites with foreign zinc fingers. Nucleic Acids Res 1998; 26:1233-9. [PMID: 9469831 PMCID: PMC147390 DOI: 10.1093/nar/26.5.1233] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Ho-endonuclease of the yeast, Saccharomyces cerevisiae, initiates a mating type switch by making a site-specific double strand break in the mating type gene, MAT. Ho is a dodecamer endonuclease and shares six of the seven intein motifs with PI- Sce I endonuclease, an intein encoded by the VMAI gene. We show that a 113 residue truncated Ho-endonuclease starting at intein motif C initiates a mating type switch in yeast. Ho is the only dodecamer endonuclease with zinc fingers. To see whether they have a role in determining site specificity we exchanged them for zinc fingers of the yeast transcription factor, Swi5. A chimeric endonuclease comprising the dodecamer motifs of Ho (C-E) and the zinc finger domain of Swi5 cleaves a Swi5 substrate plasmid in vivo. A similar chimera with the zinc fingers of SpI cleaves a GC box rich substrate plasmid. These experiments delineate a catalytic fragment of Ho-endonuclease that can be fused to various DNA binding moieties in the design of chimeric endonucleases with new site specificities.
Collapse
Affiliation(s)
- E Nahon
- Department of Life Sciences, Ben Gurion University of the Negev, Beersheba 84105, Israel
| | | |
Collapse
|
42
|
Xu H, Li Y, Mao Z, Li Y, Wu Z, Qu L, An C, Ming X, Schiemann J, Casper R, Chen Z. Rice dwarf phytoreovirus segment S11 encodes a nucleic acid binding protein. Virology 1998; 240:267-72. [PMID: 9454700 DOI: 10.1006/viro.1997.8945] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The function of rice dwarf virus segment 11 and the corresponding segments of other phytoreoviruses is not yet determined. The amino acid sequence of Pns11, encoded by segment 11, contains a putative zinc finger and five flanking basic regions at the C-terminus. The full-length Pns11 protein and three truncated derivatives, which lack the N-terminus, the zinc-finger or the C-terminal five basic regions were expressed in Escherichia coli and their nucleic acid binding properties were studied. Pns11 interacts with single- and double-stranded forms of DNA and RNA in a sequence-nonspecific manner. The truncated derivative which contains both the zinc-finger and the C-terminal basic regions has the same binding properties as the full-length Pns11. However, removal of either of these domains prevents binding activity. The binding activity of Pns11 was drastically reduced when the blots were treated with a high concentration of EDTA. Moreover, Pns11 extracted from infected rice also binds to single-stranded RNA. These data suggest that RDV Pns11 binding activity is structure-dependent and it may play an important role in virus replication and/or genome assortment.
Collapse
Affiliation(s)
- H Xu
- National Laboratory of Protein Engineering and Plant Genetic Engineering, College of Life Sciences, Peking University, Beijing, China
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
43
|
Schmiedeskamp M, Klevit RE. Paramagnetic cobalt as a probe of the orientation of an accessory DNA-binding region of the yeast ADR1 zinc-finger protein. Biochemistry 1997; 36:14003-11. [PMID: 9369471 DOI: 10.1021/bi971364f] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The minimal DNA-binding domain of the yeast ADR1 transcription factor consists of two Cys2-His2 zinc fingers and an additional 20 residues N-terminal and proximal to the fingers. The accessory sequence likely plays a role in contacting DNA. Paramagnetic cobalt was incorporated into the fingers of an ADR1 DNA-binding construct (ADR1z) to serve as a probe of the proximity of the accessory sequence to the zinc fingers. NMR signals from the accessory region are not perturbed by cobalt incorporation. Previous studies showed that this region is random coil in the ADR1z construct in the absence of DNA; it does not adopt a fixed orientation with respect to the cobalt sites. In contrast, many residues of the accessory region are perturbed by cobalt in the DNA-bound form of the protein, suggesting this region becomes constrained. This observation agrees with previous results showing a disorder-to-order transition for the accessory region upon DNA binding. Furthermore, these results indicate that the accessory region lies close to the fingers in the protein-DNA complex. This region thus does not extend along the DNA away from the zinc fingers; it more likely binds the same stretch of DNA contacted by the zinc fingers. Comparison to the behavior of other zinc-finger proteins that utilize an accessory DNA-binding sequence suggested that the region of ADR1 proximal to the zinc fingers might form an alpha-helix. Analysis of sequential NOEs in the accessory region of DNA-bound ADR1z reveals no helical structure.
Collapse
Affiliation(s)
- M Schmiedeskamp
- Biomolecular Structure Center and Department of Biochemistry, Box 357742, University of Washington, Seattle, Washington 98195-7742, USA
| | | |
Collapse
|
44
|
Schmiedeskamp M, Rajagopal P, Klevit RE. NMR chemical shift perturbation mapping of DNA binding by a zinc-finger domain from the yeast transcription factor ADR1. Protein Sci 1997; 6:1835-48. [PMID: 9300483 PMCID: PMC2143792 DOI: 10.1002/pro.5560060904] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Mutagenesis studies have revealed that the minimal DNA-binding domain of the yeast transcription factor ADR1 consists of two Cys2-His2 zinc fingers plus an additional 20 residues proximal and N-terminal to the fingers. We have assigned NMR 1H, 15N, and 13C chemical shifts for the entire minimal DNA-binding domain of ADR1 both free and bound to specific DNA. 1H chemical shift values suggest little structural difference between the zinc fingers in this construct and in single-finger constructs, and 13C alpha chemical shift index analysis indicates little change in finger structure upon DNA binding. 1H chemical shift perturbations upon DNA binding are observed, however, and these are mapped to define the protein-DNA interface. The two zinc fingers appear to bind DNA with different orientations, as the entire helix of finger 1 is perturbed, while only the extreme N-terminus of the finger 2 helix is affected. Furthermore, residues N-terminal to the first finger undergo large chemical shift changes upon DNA binding suggesting a role at the protein-DNA interface. A striking correspondence is observed between the protein-DNA interface mapped by chemical shift changes and that previously mapped by mutagenesis.
Collapse
Affiliation(s)
- M Schmiedeskamp
- Biomolecular Structure Center, University of Washington, Seattle 98195, USA
| | | | | |
Collapse
|
45
|
Narayan VA, Kriwacki RW, Caradonna JP. Structures of zinc finger domains from transcription factor Sp1. Insights into sequence-specific protein-DNA recognition. J Biol Chem 1997; 272:7801-9. [PMID: 9065444 DOI: 10.1074/jbc.272.12.7801] [Citation(s) in RCA: 100] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The carboxyl terminus of transcription factor Sp1 contains three contiguous Cys2-His2 zinc finger domains with the consensus sequence Cys-X2-4-Cys-X12-His-X3-His. We have used standard homonuclear two-dimensional NMR techniques to solve the solution structures of synthetic peptides corresponding to the last two zinc finger domains (Sp1f2 and Sp1f3, respectively) of Sp1. Our studies indicate a classical Cys2-His2 type fold for both the domains differing from each other primarily in the conformation of Cys-X2-Cys (beta-type I turn) and Cys-X4-Cys (beta-type II turn) elements. There are, however, no significant differences in the metal binding properties between the Cys-X4-Cys (Sp1f2) and Cys-X2-Cys (Sp1f3) subclasses of zinc fingers. The free solution structures of Sp1f2 and Sp1f3 are very similar to those of the analogous fingers of Zif268 bound to DNA. There is NMR spectral evidence suggesting that the Arg-Asp buttressing interaction observed in the Zif-268.DNA complex is also preserved in unbound Sp1f2 and Sp1f3. Modeling Sp1-DNA complex by overlaying the Sp1f2 and Sp1f3 structures on Zif268 fingers 1 and 2, respectively, predicts the role of key amino acid residues, the interference/protection data, and supports the model of Sp1-DNA interaction proposed earlier.
Collapse
Affiliation(s)
- V A Narayan
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, USA
| | | | | |
Collapse
|
46
|
Dutnall RN, Neuhaus D, Rhodes D. The solution structure of the first zinc finger domain of SWI5: a novel structural extension to a common fold. Structure 1996; 4:599-611. [PMID: 8736557 DOI: 10.1016/s0969-2126(96)00064-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND The 2Cys-2His (C2-H2) zinc finger is a protein domain commonly used for sequence-specific DNA recognition. The zinc fingers of the yeast transcription factors SWI5 and ACE2 share strong sequence homology, which extends into a region N-terminal to the first finger, suggesting that the DNA-binding domains of these two proteins include additional structural elements. RESULTS Structural analysis of the zinc fingers of SWI5 reveals that a 15 residue region N-terminal to the finger motifs forms part of the structure of the first finger domain, adding a beta strand and a helix not previously observed in other zinc finger structures. Sequence analysis suggests that other zinc finger proteins may also have this structure. Biochemical studies show that this additional structure increases DNA-binding affinity. CONCLUSIONS The structural analysis presented reveals a novel zinc finger structure in which additional structural elements have been added to the C2-H2 zinc finger fold. This additional structure may enhance stability and has implications for DNA recognition by extending the potential DNA-binding surface of a single zinc finger domain.
Collapse
Affiliation(s)
- R N Dutnall
- MRC Laboratory of Molecular Biology, Cambridge, UK
| | | | | |
Collapse
|
47
|
Pedone PV, Ghirlando R, Clore GM, Gronenborn AM, Felsenfeld G, Omichinski JG. The single Cys2-His2 zinc finger domain of the GAGA protein flanked by basic residues is sufficient for high-affinity specific DNA binding. Proc Natl Acad Sci U S A 1996; 93:2822-6. [PMID: 8610125 PMCID: PMC39717 DOI: 10.1073/pnas.93.7.2822] [Citation(s) in RCA: 107] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Specific DNA binding to the core consensus site GAGAGAG has been shown with an 82-residue peptide (residues 310-391) taken from the Drosophila transcription factor GAGA. Using a series of deletion mutants, it was demonstrated that the minimal domain required for specific binding (residues 310-372) includes a single zinc finger of the Cys2-His2 family and a stretch of basic amino acids located on the N-terminal end of the zinc finger. In gel retardation assays, the specific binding seen with either the peptide or the whole protein is zinc dependent and corresponds to a dissociation constant of approximately 5 x 10(-9) M for the purified peptide. It has previously been thought that a single zinc finger of the Cys2-His2 family is incapable of specific, high-affinity binding to DNA. The combination of an N-terminal basic region with a single Cys2-His2 zinc finger in the GAGA protein can thus be viewed as a novel DNA binding domain. This raises the possibility that other proteins carrying only one Cys2-His2 finger are also capable of high-affinity specific binding to DNA.
Collapse
Affiliation(s)
- P V Pedone
- Laboratory of Molecular Biology, Naional Institutes of Health, Bethesda, MD 20892-0530, USA
| | | | | | | | | | | |
Collapse
|
48
|
Brazas RM, Bhoite LT, Murphy MD, Yu Y, Chen Y, Neklason DW, Stillman DJ. Determining the requirements for cooperative DNA binding by Swi5p and Pho2p (Grf10p/Bas2p) at the HO promoter. J Biol Chem 1995; 270:29151-61. [PMID: 7493941 DOI: 10.1074/jbc.270.49.29151] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
SW15 encodes a zinc finger DNA binding protein required for the transcription of the Saccharomyces cerevisiae HO gene, and PHO2 encodes a homeodomain DNA binding protein. In vitro biochemical studies using purified Swi5p and Pho2p proteins have demonstrated that Swi5p and Pho2p bind cooperatively to the HO promoter. In this report we investigate the regions of the Swi5p and Pho2p proteins required for cooperative DNA binding. The analysis of each protein gives a similar result: the zinc finger or homeodomain DNA binding domains are each sufficient for in vitro DNA binding, but additional regions of each protein are required for cooperative DNA binding. In vitro and in vivo experiments were conducted with promoters with altered spacing between the Pho2p and Swi5p binding sites. Mutations that increased the distance between the two binding sites had minimal effects on either in vitro cooperative DNA binding or in vivo upstream activating sequence activity. These observations suggest that the interaction domains of Swi5p and Pho2p are flexible and can tolerate an increase in distance between the two binding sites. The mechanism of the cooperative DNA binding by Swi5p and Pho2p is discussed.
Collapse
Affiliation(s)
- R M Brazas
- Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City 84132, USA
| | | | | | | | | | | | | |
Collapse
|
49
|
Svetlov VV, Cooper TG. Review: compilation and characteristics of dedicated transcription factors in Saccharomyces cerevisiae. Yeast 1995; 11:1439-84. [PMID: 8750235 DOI: 10.1002/yea.320111502] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Affiliation(s)
- V V Svetlov
- Department of Microbiology and Immunology, University of Tennessee, Memphis 36163, USA
| | | |
Collapse
|
50
|
Abstract
The selective expression of a gene is achieved through the interaction of protein transcription factors with characteristic DNA sequences located in the regulatory region of the gene, which is usually distinct from the coding region. These proteins contain domains that bind specifically to the DNA sites (or response elements). Some general principles in the design of these DNA-binding domains are described, followed by examples of the different structural classes discovered so far and how they recognize their binding sites.
Collapse
Affiliation(s)
- A Klug
- MRC Laboratory of Molecular Biology, Cambridge, England
| |
Collapse
|