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Weitao T, Grandinetti G, Guo P. Revolving ATPase motors as asymmetrical hexamers in translocating lengthy dsDNA via conformational changes and electrostatic interactions in phi29, T7, herpesvirus, mimivirus, E. coli, and Streptomyces. EXPLORATION (BEIJING, CHINA) 2023; 3:20210056. [PMID: 37324034 PMCID: PMC10191066 DOI: 10.1002/exp.20210056] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Accepted: 04/28/2022] [Indexed: 06/17/2023]
Abstract
Investigations of the parallel architectures of biomotors in both prokaryotic and eukaryotic systems suggest a similar revolving mechanism in the use of ATP to drive translocation of the lengthy double-stranded (ds)DNA genomes. This mechanism is exemplified by the dsDNA packaging motor of bacteriophage phi29 that operates through revolving but not rotating dsDNA to "Push through a one-way valve". This unique and novel revolving mechanism discovered in phi29 DNA packaging motor was recently reported in other systems including the dsDNA packaging motor of herpesvirus, the dsDNA ejecting motor of bacteriophage T7, the plasmid conjugation machine TraB in Streptomyces, the dsDNA translocase FtsK of gram-negative bacteria, and the genome-packaging motor in mimivirus. These motors exhibit an asymmetrical hexameric structure for transporting the genome via an inch-worm sequential action. This review intends to delineate the revolving mechanism from a perspective of conformational changes and electrostatic interactions. In phi29, the positively charged residues Arg-Lys-Arg in the N-terminus of the connector bind the negatively charged interlocking domain of pRNA. ATP binding to an ATPase subunit induces the closed conformation of the ATPase. The ATPase associates with an adjacent subunit to form a dimer facilitated by the positively charged arginine finger. The ATP-binding induces a positive charging on its DNA binding surface via an allostery mechanism and thus the higher affinity for the negatively charged dsDNA. ATP hydrolysis induces an expanded conformation of the ATPase with a lower affinity for dsDNA due to the change of the surface charge, but the (ADP+Pi)-bound subunit in the dimer undergoes a conformational change that repels dsDNA. The positively charged lysine rings of the connector attract dsDNA stepwise and periodically to keep its revolving motion along the channel wall, thus maintaining the one-way translocation of dsDNA without reversal and sliding out. The finding of the presence of the asymmetrical hexameric architectures of many ATPases that use the revolving mechanism may provide insights into the understanding of translocation of the gigantic genomes including chromosomes in complicated systems without coiling and tangling to speed up dsDNA translocation and save energy.
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Affiliation(s)
- Tao Weitao
- UT Southwestern Medical CenterCenter for the Genetics of Host DefenseDallasTXUSA
- College of Science and MathematicsSouthwest Baptist UniversityBolivarMOUSA
| | - Giovanna Grandinetti
- Center for Electron Microscopy and AnalysisThe Ohio State UniversityColumbusOHUSA
| | - Peixuan Guo
- Center for RNA Nanobiotechnology and NanomedicineDivision of Pharmaceutics and Pharmacology, College of PharmacyDorothy M. Davis Heart and Lung Research Institute, James Comprehensive Cancer Center, College of MedicineThe Ohio State UniversityColumbusOHUSA
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Evidence of a Set of Core-Function Genes in 16 Bacillus Podoviral Genomes with Considerable Genomic Diversity. Viruses 2023; 15:v15020276. [PMID: 36851489 PMCID: PMC9965433 DOI: 10.3390/v15020276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 01/06/2023] [Accepted: 01/13/2023] [Indexed: 01/20/2023] Open
Abstract
Bacteriophage genomes represent an enormous level of genetic diversity and provide considerable potential to acquire new insights about viral genome evolution. In this study, the genome sequences of sixteen Bacillus-infecting bacteriophages were explored through comparative genomics approaches to reveal shared and unique characteristics. These bacteriophages are in the Salasmaviridae family with small (18,548-27,206 bp) double-stranded DNA genomes encoding 25-46 predicted open reading frames. We observe extensive nucleotide and amino acid sequence divergence among a set of core-function genes that present clear synteny. We identify two examples of sequence directed recombination within essential genes, as well as explore the expansion of gene content in these genomes through the introduction of novel open reading frames. Together, these findings highlight the complex evolutionary relationships of phage genomes that include old, common origins as well as new components introduced through mosaicism.
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Saeed AFUH, Chan C, Guan H, Gong B, Guo P, Cheng X, Ouyang S. Structural Insights into gp16 ATPase in the Bacteriophage ϕ29 DNA Packaging Motor. Biochemistry 2021; 60:886-897. [PMID: 33689296 DOI: 10.1021/acs.biochem.0c00935] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Biological motors, ubiquitous in living systems, convert chemical energy into different kinds of mechanical motions critical to cellular functions. Gene product 16 (gp16) in bacteriophage ϕ29 is among the most powerful biomotors known, which adopts a multisubunit ring-shaped structure and hydrolyzes ATP to package double-stranded DNA (dsDNA) into a preformed procapsid. Here we report the crystal structure of the C-terminal domain of gp16 (gp16-CTD). Structure-based alignment and molecular dynamics simulations revealed an essential binding surface of gp16-CTD for prohead RNA, a unique component of the motor complex. Furthermore, our simulations highlighted a dynamic interplay between the N-terminal domain and the CTD of gp16, which may play a role in driving movement of DNA into the procapsid. Lastly, we assembled an atomic structural model of the complete ϕ29 dsDNA packaging motor complex by integrating structural and experimental data from multiple sources. Collectively, our findings provided a refined inchworm-revolution model for dsDNA translocation in bacteriophage ϕ29 and suggested how the individual domains of gp16 work together to power such translocation.
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Affiliation(s)
- Abdullah F U H Saeed
- The Key Laboratory of Innate Immune Biology of Fujian Province, Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, Biomedical Research Center of South China, Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou 350117, China.,Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao 266237, China.,College of Chemistry and Materials Science, Fujian Normal University, Fuzhou 350117, China
| | - Chun Chan
- College of Pharmacy, The Ohio State University, Columbus, Ohio 43210, United States
| | - Hongxin Guan
- The Key Laboratory of Innate Immune Biology of Fujian Province, Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, Biomedical Research Center of South China, Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou 350117, China.,Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao 266237, China
| | - Bing Gong
- Guangxi Key Laboratory of Marine Disaster in the Beibu Gulf, Beibu Gulf University, Qinzhou 535000, China
| | - Peixuan Guo
- College of Pharmacy, The Ohio State University, Columbus, Ohio 43210, United States.,Center for RNA Nanobiotechnology and Nanomedicine, College of Medicine, Dorothy M. Davis Heart and Lung Research Institute, and Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio 43210, United States
| | - Xiaolin Cheng
- College of Pharmacy, The Ohio State University, Columbus, Ohio 43210, United States.,Biophysics Graduate Program and Translational Data Analytics Institute, The Ohio State University, Columbus, Ohio 43210, United States
| | - Songying Ouyang
- The Key Laboratory of Innate Immune Biology of Fujian Province, Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, Biomedical Research Center of South China, Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou 350117, China.,Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao 266237, China
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Translation of the long-term fundamental studies on viral DNA packaging motors into nanotechnology and nanomedicine. SCIENCE CHINA-LIFE SCIENCES 2020; 63:1103-1129. [DOI: 10.1007/s11427-020-1752-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 06/04/2020] [Indexed: 02/07/2023]
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Muthu Krishnan S. Using Chou's general PseAAC to analyze the evolutionary relationship of receptor associated proteins (RAP) with various folding patterns of protein domains. J Theor Biol 2018; 445:62-74. [DOI: 10.1016/j.jtbi.2018.02.008] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 01/24/2018] [Accepted: 02/12/2018] [Indexed: 01/31/2023]
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Shu D, Pi F, Wang C, Zhang P, Guo P. New approach to develop ultra-high inhibitory drug using the power function of the stoichiometry of the targeted nanomachine or biocomplex. Nanomedicine (Lond) 2016; 10:1881-97. [PMID: 26139124 DOI: 10.2217/nnm.15.37] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
AIMS To find methods for potent drug development by targeting to biocomplex with high copy number. METHODS Phi29 DNA packaging motor components with different stoichiometries were used as model to assay virion assembly with Yang Hui's Triangle [Formula: see text], where Z = stoichiometry, M = drugged subunits per biocomplex, p and q are the fraction of drugged and undrugged subunits in the population. RESULTS Inhibition efficiency follows a power function. When number of drugged subunits to block the function of the complex K = 1, the uninhibited biocomplex equals q(z), demonstrating the multiplicative effect of stoichiometry on inhibition with stoichiometry 1000 > 6 > 1. Complete inhibition of virus replication was found when Z = 6. CONCLUSION Drug inhibition potency depends on the stoichiometry of the targeted components of the biocomplex or nanomachine. The inhibition effect follows a power function of the stoichiometry of the target biocomplex.
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Affiliation(s)
- Dan Shu
- Department of Pharmaceutical Sciences, Markey Cancer Center, University of Kentucky, Lexington, KY 40536, USA
| | - Fengmei Pi
- Department of Pharmaceutical Sciences, Markey Cancer Center, University of Kentucky, Lexington, KY 40536, USA
| | - Chi Wang
- Department of Biostatistics & Nanobiotechnology Center, University of Kentucky, Lexington, KY 40536, USA
| | - Peng Zhang
- Department of Surgery, University of Michigan Health System, Ann Arbor, MI 48109, USA
| | - Peixuan Guo
- Department of Pharmaceutical Sciences, Markey Cancer Center, University of Kentucky, Lexington, KY 40536, USA
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An RNA Domain Imparts Specificity and Selectivity to a Viral DNA Packaging Motor. J Virol 2015; 89:12457-66. [PMID: 26423956 DOI: 10.1128/jvi.01895-15] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 09/28/2015] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED During assembly, double-stranded DNA viruses, including bacteriophages and herpesviruses, utilize a powerful molecular motor to package their genomic DNA into a preformed viral capsid. An integral component of the packaging motor in the Bacillus subtilis bacteriophage ϕ29 is a viral genome-encoded pentameric ring of RNA (prohead RNA [pRNA]). pRNA is a 174-base transcript comprised of two domains, domains I and II. Early studies initially isolated a 120-base form (domain I only) that retains high biological activity in vitro; hence, no function could be assigned to domain II. Here we define a role for this domain in the packaging process. DNA packaging using restriction digests of ϕ29 DNA showed that motors with the 174-base pRNA supported the correct polarity of DNA packaging, selectively packaging the DNA left end. In contrast, motors containing the 120-base pRNA had compromised specificity, packaging both left- and right-end fragments. The presence of domain II also provides selectivity in competition assays with genomes from related phages. Furthermore, motors with the 174-base pRNA were restrictive, in that they packaged only one DNA fragment into the head, whereas motors with the 120-base pRNA packaged several fragments into the head, indicating multiple initiation events. These results show that domain II imparts specificity and stringency to the motor during the packaging initiation events that precede DNA translocation. Heteromeric rings of pRNA demonstrated that one or two copies of domain II were sufficient to impart this selectivity/stringency. Although ϕ29 differs from other double-stranded DNA phages in having an RNA motor component, the function provided by pRNA is carried on the motor protein components in other phages. IMPORTANCE During virus assembly, genome packaging involves the delivery of newly synthesized viral nucleic acid into a protein shell. In the double-stranded DNA phages and herpesviruses, this is accomplished by a powerful molecular motor that translocates the viral DNA into a preformed viral shell. A key event in DNA packaging is recognition of the viral DNA among other nucleic acids in the host cell. Commonly, a DNA-binding protein mediates the interaction of viral DNA with the motor/head shell. Here we show that for the bacteriophage ϕ29, this essential step of genome recognition is mediated by a viral genome-encoded RNA rather than a protein. A domain of the prohead RNA (pRNA) imparts specificity and stringency to the motor by ensuring the correct orientation of DNA packaging and restricting initiation to a single event. Since this assembly step is unique to the virus, DNA packaging is a novel target for the development of antiviral drugs.
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Pi F, Vieweger M, Zhao Z, Wang S, Guo P. Discovery of a new method for potent drug development using power function of stoichiometry of homomeric biocomplexes or biological nanomotors. Expert Opin Drug Deliv 2015; 13:23-36. [PMID: 26307193 DOI: 10.1517/17425247.2015.1082544] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
INTRODUCTION Multidrug resistance and the appearance of incurable diseases inspire the quest for potent therapeutics. AREAS COVERED We review a new methodology in designing potent drugs by targeting multi-subunit homomeric biological motors, machines or complexes with Z > 1 and K = 1, where Z is the stoichiometry of the target, and K is the number of drugged subunits required to block the function of the complex. The condition is similar to a series electrical circuit of Christmas decorations: failure of one light bulb causes the entire lighting system to lose power. In most multi-subunit, homomeric biological systems, a sequential coordination or cooperative action mechanism is utilized, thus K equals 1. Drug inhibition depends on the ratio of drugged to non-drugged complexes. When K = 1, and Z > 1, the inhibition effect follows a power law with respect to Z, leading to enhanced drug potency. The hypothesis that the potency of drug inhibition depends on the stoichiometry of the targeted biological complexes was recently quantified by Yang-Hui's Triangle (or binomial distribution), and proved using a highly sensitive in vitro phi29 viral DNA packaging system. Examples of targeting homomeric bio-complexes with high stoichiometry for potent drug discovery are discussed. EXPERT OPINION Biomotors with multiple subunits are widespread in viruses, bacteria and cells, making this approach generally applicable in the development of inhibition drugs with high efficiency.
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Affiliation(s)
- Fengmei Pi
- a 1 University of Kentucky, Nanobiotechnology Center , Lexington, KY 40536, USA.,b 2 University of Kentucky, Markey Cancer Center , Lexington, KY 40536, USA.,c 3 University of Kentucky, Department of Pharmaceutical Sciences , 789 S. Limestone Street, Room # 576, Lexington, KY 40536, USA +1 859 218 0128 ; +1 859 257 1307 ;
| | - Mario Vieweger
- a 1 University of Kentucky, Nanobiotechnology Center , Lexington, KY 40536, USA.,b 2 University of Kentucky, Markey Cancer Center , Lexington, KY 40536, USA.,c 3 University of Kentucky, Department of Pharmaceutical Sciences , 789 S. Limestone Street, Room # 576, Lexington, KY 40536, USA +1 859 218 0128 ; +1 859 257 1307 ;
| | - Zhengyi Zhao
- a 1 University of Kentucky, Nanobiotechnology Center , Lexington, KY 40536, USA.,b 2 University of Kentucky, Markey Cancer Center , Lexington, KY 40536, USA.,c 3 University of Kentucky, Department of Pharmaceutical Sciences , 789 S. Limestone Street, Room # 576, Lexington, KY 40536, USA +1 859 218 0128 ; +1 859 257 1307 ;
| | - Shaoying Wang
- a 1 University of Kentucky, Nanobiotechnology Center , Lexington, KY 40536, USA.,b 2 University of Kentucky, Markey Cancer Center , Lexington, KY 40536, USA.,c 3 University of Kentucky, Department of Pharmaceutical Sciences , 789 S. Limestone Street, Room # 576, Lexington, KY 40536, USA +1 859 218 0128 ; +1 859 257 1307 ;
| | - Peixuan Guo
- a 1 University of Kentucky, Nanobiotechnology Center , Lexington, KY 40536, USA.,b 2 University of Kentucky, Markey Cancer Center , Lexington, KY 40536, USA.,c 3 University of Kentucky, Department of Pharmaceutical Sciences , 789 S. Limestone Street, Room # 576, Lexington, KY 40536, USA +1 859 218 0128 ; +1 859 257 1307 ;
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Fang H, Zhang P, Huang LP, Zhao Z, Pi F, Montemagno C, Guo P. Binomial distribution for quantification of protein subunits in biological nanoassemblies and functional nanomachines. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2014; 10:1433-40. [PMID: 24650885 DOI: 10.1016/j.nano.2014.03.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Revised: 02/21/2014] [Accepted: 03/05/2014] [Indexed: 11/30/2022]
Abstract
Living systems produce ordered structures and nanomachines that inspire the development of biomimetic nanodevices such as chips, MEMS, actuators, sensors, sorters, and apparatuses for single-pore DNA sequencing, disease diagnosis, drug or therapeutic RNA delivery. Determination of the copy numbers of subunits that build these machines is challenging due to small size. Here we report a simple mathematical method to determine the stoichiometry, using phi29 DNA-packaging nanomotor as a model to elucidate the application of a formula ∑M=0(Z)((Z)M)p(Z-M)q(M), where p and q are the percentage of wild-type and inactive mutant in the empirical assay; M is the copy numbers of mutant and Z is the stoichiometry in question. Variable ratios of mutants and wild-type were mixed to inhibit motor function. Empirical data were plotted over the theoretical curves to determine the stoichiometry and the value of K, which is the number of mutant needed in each machine to block the function, all based on the condition that wild-type and mutant are equal in binding affinity. Both Z and K from 1-12 were investigated. The data precisely confirmed that phi29 motor contains six copies (Z) of the motor ATPase gp16, and K=1. From the clinical editor: To determine copy numbers of subunits that form nanomachines in living organisms is a daunting task due to the complexities and the inherently small sizes associated with such systems. In this paper, a simple mathematical method is described how to determine the stoichiometry of copies in biomimetic nanodevices, using phi29 DNA-packaging nanomotor as a model.
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Affiliation(s)
- Huaming Fang
- Nanobiotechnology Center, Department of Pharmaceutical Sciences, and Markey Cancer Center, University of Kentucky, Lexington, KY, USA
| | - Peng Zhang
- Department of Surgery, University of Michigan, Ann Arbor, MI, USA
| | - Lisa P Huang
- Oncoveda, Tumor Biology Center, Medical Diagnostic Laboratories, L.L.C., Hamilton, NJ, USA
| | - Zhengyi Zhao
- Nanobiotechnology Center, Department of Pharmaceutical Sciences, and Markey Cancer Center, University of Kentucky, Lexington, KY, USA
| | - Fengmei Pi
- Nanobiotechnology Center, Department of Pharmaceutical Sciences, and Markey Cancer Center, University of Kentucky, Lexington, KY, USA
| | - Carlo Montemagno
- National Institute for Nanobiotechnology, Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Canada
| | - Peixuan Guo
- Nanobiotechnology Center, Department of Pharmaceutical Sciences, and Markey Cancer Center, University of Kentucky, Lexington, KY, USA.
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Insights into the structure and assembly of the bacteriophage 29 double-stranded DNA packaging motor. J Virol 2014; 88:3986-96. [PMID: 24403593 DOI: 10.1128/jvi.03203-13] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED The tailed double-stranded DNA (dsDNA) bacteriophage 29 packages its 19.3-kbp genome into a preassembled procapsid structure by using a transiently assembled phage-encoded molecular motor. This process is remarkable considering that compaction of DNA to near-crystalline densities within the confined space of the capsid requires that the packaging motor work against significant entropic, enthalpic, and DNA-bending energies. The motor consists of three phage-encoded components: the dodecameric connector protein gp10, an oligomeric RNA molecule known as the prohead RNA (pRNA), and the homomeric ring ATPase gp16. Although atomic resolution structures of the connector and different pRNA subdomains have been determined, the mechanism of self-assembly and the resulting stoichiometry of the various motor components on the phage capsid have been the subject of considerable controversy. Here a subnanometer asymmetric cryoelectron microscopy (cryo-EM) reconstruction of a connector-pRNA complex at a unique vertex of the procapsid conclusively demonstrates the pentameric symmetry of the pRNA and illuminates the relative arrangement of the connector and the pRNA. Additionally, a combination of biochemical and cryo-EM analyses of motor assembly intermediates suggests a sequence of molecular events that constitute the pathway by which the motor assembles on the head, thereby reconciling conflicting data regarding pRNA assembly and stoichiometry. Taken together, these data provide new insight into the assembly, structure, and mechanism of a complex molecular machine. IMPORTANCE Viruses consist of a protein shell, or capsid, that protects and surrounds their genetic material. Thus, genome encapsidation is a fundamental and essential step in the life cycle of any virus. In dsDNA viruses, powerful molecular motors essentially pump the viral DNA into a preformed protein shell. This article describes how a viral dsDNA packaging motor self-assembles on the viral capsid and provides insight into its mechanism of action.
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Zhang H, Endrizzi JA, Shu Y, Haque F, Sauter C, Shlyakhtenko LS, Lyubchenko Y, Guo P, Chi YI. Crystal structure of 3WJ core revealing divalent ion-promoted thermostability and assembly of the Phi29 hexameric motor pRNA. RNA (NEW YORK, N.Y.) 2013; 19:1226-37. [PMID: 23884902 PMCID: PMC3753930 DOI: 10.1261/rna.037077.112] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Accepted: 06/06/2013] [Indexed: 05/22/2023]
Abstract
The bacteriophage phi29 DNA packaging motor, one of the strongest biological motors characterized to date, is geared by a packaging RNA (pRNA) ring. When assembled from three RNA fragments, its three-way junction (3WJ) motif is highly thermostable, is resistant to 8 M urea, and remains associated at extremely low concentrations in vitro and in vivo. To elucidate the structural basis for its unusual stability, we solved the crystal structure of this pRNA 3WJ motif at 3.05 Å. The structure revealed two divalent metal ions that coordinate 4 nt of the RNA fragments. Single-molecule fluorescence resonance energy transfer (smFRET) analysis confirmed a structural change of 3WJ upon addition of Mg²⁺. The reported pRNA 3WJ conformation is different from a previously published construct that lacks the metal coordination sites. The phi29 DNA packaging motor contains a dodecameric connector at the vertex of the procapsid, with a central pore for DNA translocation. This portal connector serves as the foothold for pRNA binding to procapsid. Subsequent modeling of a connector/pRNA complex suggests that the pRNA of the phi29 DNA packaging motor exists as a hexameric complex serving as a sheath over the connector. The model of hexameric pRNA on the connector agrees with AFM images of the phi29 pRNA hexamer acquired in air and matches all distance parameters obtained from cross-linking, complementary modification, and chemical modification interference.
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Affiliation(s)
- Hui Zhang
- Nanobiotechnology Center, Markey Cancer Center and Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky 40536, USA
| | - James A. Endrizzi
- Section of Structural Biology, Hormel Institute, University of Minnesota, Austin, Minnesota 55912, USA
| | - Yi Shu
- Nanobiotechnology Center, Markey Cancer Center and Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky 40536, USA
| | - Farzin Haque
- Nanobiotechnology Center, Markey Cancer Center and Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky 40536, USA
| | - Claude Sauter
- Institut de Biologie Moléculaire et Cellulaire (IBMC-ARN-CNRS) Cristallogenèse & Biologie Structurale, F-67084 Strasbourg, France
| | - Lyudmila S. Shlyakhtenko
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha, Nebraska 68198, USA
| | - Yuri Lyubchenko
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha, Nebraska 68198, USA
| | - Peixuan Guo
- Nanobiotechnology Center, Markey Cancer Center and Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky 40536, USA
- Corresponding authorsE-mail E-mail
| | - Young-In Chi
- Section of Structural Biology, Hormel Institute, University of Minnesota, Austin, Minnesota 55912, USA
- Corresponding authorsE-mail E-mail
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Guo P, Schwartz C, Haak J, Zhao Z. Discovery of a new motion mechanism of biomotors similar to the earth revolving around the sun without rotation. Virology 2013; 446:133-43. [PMID: 24074575 PMCID: PMC3941703 DOI: 10.1016/j.virol.2013.07.025] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Revised: 05/27/2013] [Accepted: 07/21/2013] [Indexed: 12/14/2022]
Abstract
Biomotors have been classified into linear and rotational motors. For 35 years, it has been popularly believed that viral dsDNA-packaging apparatuses are pentameric rotation motors. Recently, a third class of hexameric motor has been found in bacteriophage phi29 that utilizes a mechanism of revolution without rotation, friction, coiling, or torque. This review addresses how packaging motors control dsDNA one-way traffic; how four electropositive layers in the channel interact with the electronegative phosphate backbone to generate four steps in translocating one dsDNA helix; how motors resolve the mismatch between 10.5 bases and 12 connector subunits per cycle of revolution; and how ATP regulates sequential action of motor ATPase. Since motors with all number of subunits can utilize the revolution mechanism, this finding helps resolve puzzles and debates concerning the oligomeric nature of packaging motors in many phage systems. This revolution mechanism helps to solve the undesirable dsDNA supercoiling issue involved in rotation.
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Affiliation(s)
- Peixuan Guo
- Nanobiotechnology Center, and Markey Cancer Center, Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536, USA.
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Schwartz C, De Donatis GM, Fang H, Guo P. The ATPase of the phi29 DNA packaging motor is a member of the hexameric AAA+ superfamily. Virology 2013; 443:20-7. [PMID: 23706809 PMCID: PMC3700617 DOI: 10.1016/j.virol.2013.04.004] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Revised: 04/01/2013] [Accepted: 04/07/2013] [Indexed: 12/21/2022]
Abstract
The AAA+ superfamily of proteins is a class of motor ATPases performing a wide range of functions that typically exist as hexamers. The ATPase of phi29 DNA packaging motor has long been a subject of debate in terms of stoichiometry and mechanism of action. Here, we confirmed the stoichiometry of phi29 motor ATPase to be a hexamer and provide data suggesting that the phi29 motor ATPase is a member of the classical hexameric AAA+ superfamily. Native PAGE, EMSA, capillary electrophoresis, ATP titration, and binomial distribution assay show that the ATPase is a hexamer. Mutations in the known Walker motifs of the ATPase validated our previous assumptions that the protein exists as another member of this AAA+ superfamily. Our data also supports the finding that the phi29 DNA packaging motor uses a revolution mechanism without rotation or coiling (Schwartz et al., this issue).
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Affiliation(s)
| | | | | | - Peixuan Guo
- Nanobiotechnology Center, College of Pharmacy and Markey Cancer Center,
University of Kentucky, Lexington, KY, USA
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Ponchon L, Catala M, Seijo B, El Khouri M, Dardel F, Nonin-Lecomte S, Tisné C. Co-expression of RNA-protein complexes in Escherichia coli and applications to RNA biology. Nucleic Acids Res 2013; 41:e150. [PMID: 23804766 PMCID: PMC3753655 DOI: 10.1093/nar/gkt576] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
RNA has emerged as a major player in many cellular processes. Understanding these processes at the molecular level requires homogeneous RNA samples for structural, biochemical and pharmacological studies. We previously devised a generic approach that allows efficient in vivo expression of recombinant RNA in Escherichia coli. In this work, we have extended this method to RNA/protein co-expression. We have engineered several plasmids that allow overexpression of RNA–protein complexes in E. coli. We have investigated the potential of these tools in many applications, including the production of nuclease-sensitive RNAs encapsulated in viral protein pseudo-particles, the co-production of non-coding RNAs with chaperone proteins, the incorporation of a post-transcriptional RNA modification by co-production with the appropriate modifying enzyme and finally the production and purification of an RNA–His-tagged protein complex by nickel affinity chromatography. We show that this last application easily provides pure material for crystallographic studies. The new tools we report will pave the way to large-scale structural and molecular investigations of RNA function and interactions with proteins.
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Affiliation(s)
- Luc Ponchon
- CNRS, UMR 8015, Laboratoire de Cristallographie et RMN biologiques, 4 avenue de l'Observatoire, 75006 Paris, France and Université Paris Descartes, Sorbonne Paris Cité, UMR 8015, Laboratoire de Cristallographie et RMN biologiques, 4 avenue de l'Observatoire, 75006 Paris, France
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15
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Incorporation of a viral DNA-packaging motor channel in lipid bilayers for real-time, single-molecule sensing of chemicals and double-stranded DNA. Nat Protoc 2013; 8:373-92. [PMID: 23348364 DOI: 10.1038/nprot.2013.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Over the past decade, nanopores have rapidly emerged as stochastic biosensors. This protocol describes the cloning, expression and purification of the channel of the bacteriophage phi29 DNA-packaging nanomotor and its subsequent incorporation into lipid membranes for single-pore sensing of double-stranded DNA (dsDNA) and chemicals. The membrane-embedded phi29 nanochannel remains functional and structurally intact under a range of conditions. When ions and macromolecules translocate through this nanochannel, reliable fingerprint changes in conductance are observed. Compared with other well-studied biological pores, the phi29 nanochannel has a larger cross-sectional area, which enables the translocation of dsDNA. Furthermore, specific amino acids can be introduced by site-directed mutagenesis within the large cavity of the channel to conjugate receptors that are able to bind specific ligands or analytes for desired applications. The lipid membrane-embedded nanochannel system has immense potential nanotechnological and biomedical applications in bioreactors, environmental sensing, drug monitoring, controlled drug delivery, early disease diagnosis and high-throughput DNA sequencing. The total time required for completing one round of this protocol is around 1 month.
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16
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Zhang H, Schwartz C, De Donatis GM, Guo P. "Push through one-way valve" mechanism of viral DNA packaging. Adv Virus Res 2012; 83:415-65. [PMID: 22748815 DOI: 10.1016/b978-0-12-394438-2.00009-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Double-stranded (ds)DNA viruses package their genomic DNA into a procapsid using a force-generating nanomotor powered by ATP hydrolysis. Viral DNA packaging motors are mainly composed of the connector channel and two DNA packaging enzymes. In 1998, it was proposed that viral DNA packaging motors exercise a mechanism similar to the action of AAA+ ATPases that assemble into ring-shaped oligomers, often hexamers, with a central channel (Guo et al. Molecular Cell, 2:149). This chapter focuses on the most recent findings in the bacteriophage ϕ29 DNA packaging nanomotor to address this intriguing notion. Almost all dsDNA viruses are composed entirely of protein, but in the unique case of ϕ29, packaging RNA (pRNA) plays an intermediate role in the packaging process. Evidence revealed that DNA packaging is accomplished via a "push through one-way valve" mechanism. The ATPase gp16 pushes dsDNA through the connector channel section by section into the procapsid. The dodecameric connector channel functions as a one-way valve that only allows dsDNA to enter but not exit the procapsid during DNA packaging. Although the roles of the ATPase gp16 and the motor connector channel are separate and independent, pRNA bridges these two components to ensure the coordination of an integrated motor. ATP induces a conformational change in gp16, leading to its stronger binding to dsDNA. Furthermore, ATP hydrolysis led to the departure of dsDNA from the ATPase/dsDNA complex, an action used to push dsDNA through the connector channel. It was found unexpectedly that by mutating the basic lysine rings of the connector channel or by changing the pH did not measurably impair DNA translocation or affect the one-way traffic property of the channel, suggesting that the positive charges in the lysine ring are not essential in gearing the dsDNA. The motor channel exercises three discrete, reversible, and controllable steps of gating, with each step altering the channel size by 31% to control the direction of translocation of dsDNA. Many DNA packaging models have been contingent upon the number of base pairs packaged per ATP relative to helical turns for B-type DNA. Both 2 and 2.5 bp per ATP have been used to argue for four, five, or six discrete steps of DNA translocation. The "push through one-way valve" mechanism renews the perception of dsDNA packaging energy calculations and provides insight into the discrepancy between 2 and 2.5 bp per ATP. Application of the DNA packaging motor in nanotechnology and nanomedicine is also addressed. Comparison with nine other DNA packaging models revealed that the "push through one-way valve" is the most agreeable mechanism to interpret most of the findings that led to historical models. The application of viral DNA packaging motors is also discussed.
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Affiliation(s)
- Hui Zhang
- Nanobiotechnology Center, Department of Pharmaceutical Sciences, and Markey Cancer Center, University of Kentucky, Lexington, KY, USA
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17
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Ye X, Hemida M, Zhang HM, Hanson P, Ye Q, Yang D. Current advances in Phi29 pRNA biology and its application in drug delivery. WILEY INTERDISCIPLINARY REVIEWS-RNA 2012; 3:469-81. [PMID: 22362726 DOI: 10.1002/wrna.1111] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Bacteriophage 29 (Phi29) packaging RNA (pRNA) is one of the key components in the viral DNA-packaging motor. It contains two functional domains facilitating the translocation of DNA into the viral capsid by interacting with other elements in the motor and promoting adenosine triphosphates hydrolysis. Through the connection between interlocking loops in adjacent pRNA monomers, pRNA functions in the form of multimer ring in the motor. Previous studies have addressed the unique structure and conformation of pRNA. However, there are different DNA-packaging models proposed for the viral genome transportation mechanism. The DNA-packaging ability and the unique features of pRNA have been attracting efforts to study its potential applications in nanotechnology. The pRNA has been proved to be a promising tool for delivering nucleic acid-based therapeutic molecules by covalent linkage with ribozymes, small interfering RNAs, aptamers, and artificial microRNAs. The flexibility in constructing dimers, trimers, and hexamers enables the assembly of polyvalent nanoparticles to carry drug molecules for therapeutic purposes, cell ligands for target delivery, image detector for drug entry monitoring, and endosome disrupter for drug release. Besides these fascinating pharmacological advantages, pRNA-based drug delivery has also been demonstrated to prolong the drug half life with minimal induction of immune response and toxicity.
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Affiliation(s)
- Xin Ye
- The Institute for Heart and Lung Health, St. Paul's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
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18
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Role of channel lysines and the "push through a one-way valve" mechanism of the viral DNA packaging motor. Biophys J 2012; 102:127-35. [PMID: 22225806 PMCID: PMC3250684 DOI: 10.1016/j.bpj.2011.11.4013] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Revised: 10/27/2011] [Accepted: 11/14/2011] [Indexed: 11/22/2022] Open
Abstract
Linear double-stranded DNA (dsDNA) viruses package their genomes into preformed protein shells via nanomotors using ATP as an energy source. The central hub of the bacteriophage φ29 DNA-packaging motor contains a 3.6-nm channel for dsDNA to enter during packaging and to exit during infection. The negatively charged interior channel wall is decorated with a total of 48 positively charged lysine residues displayed as four 12-lysine rings from the 12 gp10 subunits that enclose the channel. The standard notion derived from many models is that these uniquely arranged, positively charged rings play active roles in DNA translocation through the channel. In this study, we tested this prevailing view by examining the effect of mutating these basic lysines to alanines, and assessing the impact of altering the pH environment. Unexpectedly, mutating these basic lysine residues or changing the pH to 4 or 10, which could alter the charge of lysines, did not measurably impair DNA translocation or affect the one-way traffic property of the channel. The results support our recent findings regarding the dsDNA packaging mechanism known as the "push through a one-way valve".
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19
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Morais MC. The dsDNA Packaging Motor in Bacteriophage ø29. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 726:511-47. [DOI: 10.1007/978-1-4614-0980-9_23] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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20
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Shu D, Shu Y, Haque F, Abdelmawla S, Guo P. Thermodynamically stable RNA three-way junction for constructing multifunctional nanoparticles for delivery of therapeutics. NATURE NANOTECHNOLOGY 2011; 6:658-67. [PMID: 21909084 PMCID: PMC3189281 DOI: 10.1038/nnano.2011.105] [Citation(s) in RCA: 328] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2011] [Accepted: 06/08/2011] [Indexed: 05/12/2023]
Abstract
RNA nanoparticles have applications in the treatment of cancers and viral infection; however, the instability of RNA nanoparticles has hindered their development for therapeutic applications. The lack of covalent linkage or crosslinking in nanoparticles causes dissociation in vivo. Here we show that the packaging RNA of bacteriophage phi29 DNA packaging motor can be assembled from 3-6 pieces of RNA oligomers without the use of metal salts. Each RNA oligomer contains a functional module that can be a receptor-binding ligand, aptamer, short interfering RNA or ribozyme. When mixed together, they self-assemble into thermodynamically stable tri-star nanoparticles with a three-way junction core. These nanoparticles are resistant to 8 M urea denaturation, are stable in serum and remain intact at extremely low concentrations. The modules remain functional in vitro and in vivo, suggesting that the three-way junction core can be used as a platform for building a variety of multifunctional nanoparticles. We studied 25 different three-way junction motifs in biological RNA and found only one other motif that shares characteristics similar to the three-way junction of phi29 pRNA.
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Affiliation(s)
- Dan Shu
- Nanobiomedical Center, University of Cincinnati, Cincinnati, OH 45267
| | - Yi Shu
- Nanobiomedical Center, University of Cincinnati, Cincinnati, OH 45267
| | - Farzin Haque
- Nanobiomedical Center, University of Cincinnati, Cincinnati, OH 45267
| | - Sherine Abdelmawla
- Kylin Therapeutics, Inc, West Lafayette, IN 47906
- Bindley Bioscience Center, Purdue University, West Lafayette, IN 47906
| | - Peixuan Guo
- Nanobiomedical Center, University of Cincinnati, Cincinnati, OH 45267
- Address correspondence to: Peixuan Guo, Rm 1436, ML #0508, Vontz Center for Molecular Studies, 3125 Eden Avenue, University of Cincinnati, Cincinnati, OH 45267, USA, , Phone: (513)558-0041, Fax: (513)558-6079
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21
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Harris S, Schroeder SJ. Nuclear magnetic resonance structure of the prohead RNA E-loop hairpin. Biochemistry 2010; 49:5989-97. [PMID: 20550192 DOI: 10.1021/bi100393r] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The Bacillus subtilis phage phi29 packaging motor requires prohead RNA for genome encapsidation. The nuclear magnetic resonance structure of the prohead RNA E-loop hairpin, r(5'AUUGAGUU), is presented and compared to predictions from MC-SYM. The prohead RNA E-loop hairpins contain sequences similar to rRNA hairpins. Comparison of predicted and experimentally determined prohead and ribosomal hairpin structures reveals that sequence similarity is a stronger determinant of hairpin structural similarity than grouping similar types of RNA. All the hairpins contain a U-turn motif but differ in the first noncanonical pair and backbone orientation. These structures provide benchmarks for further improvements in RNA structure predictions from sequence.
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Affiliation(s)
- Steven Harris
- Department of Chemistry and Biochemistry, University of Oklahoma, 620 Parrington Oval, Norman, Oklahoma 73019, USA
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22
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Xiao F, Demeler B, Guo P. Assembly mechanism of the sixty-subunit nanoparticles via interaction of RNA with the reengineered protein connector of phi29 DNA-packaging motor. ACS NANO 2010; 4:3293-301. [PMID: 20509670 PMCID: PMC2889630 DOI: 10.1021/nn100158k] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2009] [Accepted: 05/19/2010] [Indexed: 05/19/2023]
Abstract
Bacterial virus phi29 genomic DNA is packaged into a procapsid shell with the aid of a motor containing a 12-subunit connector channel and a hexameric pRNA (packaging RNA) ring. The wide end, or the C-terminus, of the cone-shaped connector is embedded within the procapsid shell, whereas the narrow end, or N-terminus, extends outside of the procapsid, providing a binding location for pRNA. Recently, we have reported the mechanism of in vivo assembly of an ellipsoid nanoparticle with seven connectors through an interaction among a peptide tag. Here we report the formation of a similar nanoparticle in vitro via the addition of DNA or RNA oligos to connector proteins. Free connectors guided by one or two copies of oligonucleotides were assembled into a rosette structure containing 60 subunits of reengineered proteins. The number of oligonucleotides within the particle is length-dependent but sequence-independent. Reversible shifting between the 12- and 60-subunit nanoparticles (between individual connectors and rosette structures, respectively) was demonstrated by the alternative addition of oligonucleotides and the treatment of ribonuclease, suggesting a potential application as a switch or regulator in nanobiotechnology. This advancement allows for a simple method to produce multivalent nanoparticles that contain five 12-unit nanoparticles with defined structure and stoichiometry. That is, it will be possible to assemble nanoparticles in vitro with the combination of 60 assortments of ligands, tags, therapeutic drugs, and diagnostic moieties for multivalent delivery or enhancement of signal detection in nanotechnological and nanomedicinal applications.
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Affiliation(s)
- Feng Xiao
- Department of Biomedical Engineering, College of Engineering/College of Medicine, University of Cincinnati, Cincinnati, Ohio 45267
| | - Borries Demeler
- Department of Biochemistry, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, Texas 78229
| | - Peixuan Guo
- Department of Biomedical Engineering, College of Engineering/College of Medicine, University of Cincinnati, Cincinnati, Ohio 45267
- Address correspondence to
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23
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Zhang H, Shu D, Wang W, Guo P. Design and application of single fluorophore dual-view imaging system containing both the objective- and prism-type TIRF. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2010; 7571:757107-757108. [PMID: 20436791 DOI: 10.1117/12.847457] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Simultaneous detection of two fluorescent markers is important in determination of distance, relative motion and conformational change of nanoparticles or nanodevices. We constructed an imaging system which combines deep-cooled sensitive EMCCD camera with both the objective- and prism-type TIRF. A laser combiner was introduced to facilitate laser controls for simultaneous dual-channel imaging by deliver lasers with different wavelength synchronically via an optic fiber to the sample. The system produces stable signal with extremely low background fluorescence for single-fluorophore detection. It has been applied to study the structure, stoichiometry, and function of the phi29 DNA packaging motor. Single-molecule photobleaching combined with binomial distribution analysis clarified the stoichiometry of pRNA on the motor and elucidated the mechanism of pRNA hexamer assembly. The feasibility of single-molecule FRET with this system was demonstrated. Distance rulers of dual-labeled molecule standards were used to evaluate the system. We have also re-engineered the energy conversion protein, gp16, of phi29 motor for single fluorophore labeling to facilitate the single-molecule studies of motor mechanism. The potential applications of single-molecule high-resolution imaging with photobleaching (SHRImP) and single molecule high resolution with co-localization (SHREC) approaches to the study of the phi29 nanomotor are under investigation.
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Affiliation(s)
- Hui Zhang
- Department of Biomedical Engineering, College of Engineering and College of Medicine, University of Cincinnati, Cincinnati, OH 45221, USA
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24
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Construction of bacteriophage phi29 DNA packaging motor and its applications in nanotechnology and therapy. Ann Biomed Eng 2009; 37:2064-81. [PMID: 19495981 DOI: 10.1007/s10439-009-9723-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2008] [Accepted: 05/20/2009] [Indexed: 01/16/2023]
Abstract
Nanobiotechnology involves the creation, characterization, and modification of organized nanomaterials to serve as building blocks for constructing nanoscale devices in technology and medicine. Living systems contain a wide variety of nanomachines and highly ordered structures of macromolecules. The novelty and ingenious design of the bacterial virus phi29 DNA packaging motor and its parts inspired the synthesis of this motor and its components as biomimetics. This 30-nm nanomotor uses six copies of an ATP-binding pRNA to gear the motor. The structural versatility of pRNA has been utilized to construct dimers, trimers, hexamers, and patterned superstructures via the interaction of two interlocking loops. The approach, based on bottom-up assembly, has also been applied to nanomachine fabrication, pathogen detection and the delivery of drugs, siRNA, ribozymes, and genes to specific cells in vitro and in vivo. Another essential component of the motor is the connector, which contains 12 copies of a protein gp10 to form a 3.6-nm central channel as a path for DNA. This article will review current studies of the structure and function of the phi29 DNA packaging motor, as well as the mechanism of motion, the principle of in vitro construction, and its potential nanotechnological and medical applications.
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25
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Xiao F, Sun J, Coban O, Schoen P, Wang JCY, Cheng RH, Guo P. Fabrication of massive sheets of single layer patterned arrays using lipid directed reengineered phi29 motor dodecamer. ACS NANO 2009; 3:100-107. [PMID: 19206255 PMCID: PMC2651733 DOI: 10.1021/nn800409a] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2008] [Accepted: 11/24/2008] [Indexed: 05/27/2023]
Abstract
The bottom-up assembly of patterned arrays is an exciting and important area in current nanotechnology. Arrays can be engineered to serve as components in chips for a virtually inexhaustible list of applications ranging from disease diagnosis to ultra-high-density data storage. Phi29 motor dodecamer has been reported to form elegant multilayer tetragonal arrays. However, multilayer protein arrays are of limited use for nanotechnological applications which demand nanoreplica or coating technologies. The ability to produce a single layer array of biological structures with high replication fidelity represents a significant advance in the area of nanomimetics. In this paper, we report on the assembly of single layer sheets of reengineered phi29 motor dodecamer. A thin lipid monolayer was used to direct the assembly of massive sheets of single layer patterned arrays of the reengineered motor dodecamer. Uniform, clean and highly ordered arrays were constructed as shown by both transmission electron microscopy and atomic force microscopy imaging.
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Affiliation(s)
- Feng Xiao
- Department of Biomedical Engineering, University of Cincinnati, Cincinnati, Ohio 45221
| | - Jinchuan Sun
- Lineberger Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599
| | - Oana Coban
- Department of Biomedical Engineering, University of Cincinnati, Cincinnati, Ohio 45221
| | - Peter Schoen
- Department of Scanning Probe Microscopy and Biophysical Chemistry, Radboud University, Nijmegen, The Netherlands
| | - Joseph Che-Yen Wang
- Department of Molecular & Cellular Biology, University of California, Davis, California 95616
| | - R. Holland Cheng
- Department of Molecular & Cellular Biology, University of California, Davis, California 95616
| | - Peixuan Guo
- Department of Biomedical Engineering, University of Cincinnati, Cincinnati, Ohio 45221
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Xiao F, Zhang H, Guo P. Novel mechanism of hexamer ring assembly in protein/RNA interactions revealed by single molecule imaging. Nucleic Acids Res 2008; 36:6620-32. [PMID: 18940870 PMCID: PMC2582624 DOI: 10.1093/nar/gkn669] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Many nucleic acid-binding proteins and the AAA+ family form hexameric rings, but the mechanism of hexamer assembly is unclear. It is generally believed that the specificity in protein/RNA interaction relies on molecular contact through a surface charge or 3D structure matching via conformational capture or induced fit. The pRNA of bacteriophage phi29 DNA-packaging motor also forms a ring, but whether the pRNA ring is a hexamer or a pentamer is under debate. Here, single molecule studies elucidated a mechanism suggesting the specificity and affinity in protein/RNA interaction relies on pRNA static ring formation. A combined pRNA ring-forming group was very specific for motor binding, but the isolated individual members of the ring-forming group bind to the motor nonspecifically. pRNA did not form a ring prior to motor binding. Only those RNAs that formed a static ring, via the interlocking loops, stayed on the motor. Single interlocking loop interruption resulted in pRNA detachment. Extension or reduction of the ring circumference failed in motor binding. This new mechanism was tested by redesigning two artificial RNAs that formed hexamer and packaged DNA. The results confirmed the stoichiometry of pRNA on the motor was the common multiple of two and three, thus, a hexamer.
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Affiliation(s)
- Feng Xiao
- Department of Biomedical Engineering, College of Engineering/College of Medicine, University of Cincinnati, Cincinnati, OH 45221, USA
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27
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Morais MC, Koti JS, Bowman VD, Reyes-Aldrete E, Anderson DL, Rossmann MG. Defining molecular and domain boundaries in the bacteriophage phi29 DNA packaging motor. Structure 2008; 16:1267-74. [PMID: 18682228 DOI: 10.1016/j.str.2008.05.010] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2008] [Revised: 05/14/2008] [Accepted: 05/18/2008] [Indexed: 12/17/2022]
Abstract
Cryo-electron microscopy (cryo-EM) studies of the bacteriophage phi29 DNA packaging motor have delineated the relative positions and molecular boundaries of the 12-fold symmetric head-tail connector, the 5-fold symmetric prohead RNA (pRNA), the ATPase that provides the energy for packaging, and the procapsid. Reconstructions, assuming 5-fold symmetry, were determined for proheads with 174-base, 120-base, and 71-base pRNA; proheads lacking pRNA; proheads with ATPase bound; and proheads in which the packaging motor was missing the connector. These structures are consistent with pRNA and ATPase forming a pentameric motor component around the unique vertex of proheads. They suggest an assembly pathway for the packaging motor and a mechanism for DNA translocation into empty proheads.
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Affiliation(s)
- Marc C Morais
- Department of Biochemistry and Molecular Biology, 301 University Boulevard, University of Texas Medical Branch, Galveston, TX 77555-0647, USA
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Poliakov A, Jardine P, Prevelige PE. Hydrogen/deuterium exchange on protein solutions containing nucleic acids: utility of protamine sulfate. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2008; 22:2423-2428. [PMID: 18634111 DOI: 10.1002/rcm.3627] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Obtaining global hydrogen/deuterium (H/D) exchange data on proteins is an important first step in amide proton exchange experiments. Important information such as the mode of exchange, the cooperativity of folding/unfolding reactions, and the effects of ligand binding can be readily obtained in global exchange experiments. Many interesting biological systems are complexes containing both proteins and nucleic acids. The low pH conditions required to quench H/D exchange reactions result in the formation of stable protein/nucleic acid precipitates which interfere with the liquid chromatography step of the experiment and preclude obtaining mass spectrometric data. In this work we show that the precipitation of proteins and nucleic acids is electrostatic in nature and can be prevented by high ionic strength and by removing nucleic acids by protamine sulfate. Using protamine sulfate in quenching solution, we were able to obtain global H/D data with protein samples containing large amounts of DNA or RNA.
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Affiliation(s)
- Anton Poliakov
- Department of Microbiology, University of Alabama at Birmingham, 1900 University Boulevard, Birmingham, AL 35294, USA.
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29
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Cai Y, Xiao F, Guo P. The effect of N- or C-terminal alterations of the connector of bacteriophage phi29 DNA packaging motor on procapsid assembly, pRNA binding, and DNA packaging. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2008; 4:8-18. [PMID: 18201942 DOI: 10.1016/j.nano.2007.10.084] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2007] [Revised: 09/27/2007] [Accepted: 10/11/2007] [Indexed: 01/13/2023]
Abstract
Double-stranded DNA viruses package their genomes into procapsids via an ATP-driven nanomotor. This ingenious motor configuration has inspired the development of biomimetics in nanotechnology. Bacteriophage varphi29 DNA-packaging motor has been a popular tool in nanomedicine. To provide information for further motor modification, conjugation, labeling, and manufacturing, the connector protein gp10 of the varphi29 DNA packaging motor was truncated, mutated, and extended. A 25-residue deletion or a 14-residue extension at the C terminus of gp10 did not affect procapsid assembly. A 42-amino acid extension at the N terminus did not interfere with the procapsid assembly but significantly decreased the DNA-packaging efficiency. DNA-packaging activity was restored upon protease cleavage of the extended region. Replacing the N-terminal peptide containing arginine and lysine with a histidine-rich peptide did not affect procapsid assembly but completely inhibited the packaging RNA (pRNA) binding to the connector and hindered subsequent DNA packaging. These results indicate that (1) the N-terminal arginine-lysine residues play a critical role in pRNA binding but are not essential for procapsid assembly; (2) the connector core, but not the flexible N- or C-terminal domains, is responsible for signaling the procapsid assembly; (3) pRNA binds to the connector as a result of electrostatic interactions between the polyanionic nature of nucleic acids and the cationic side groups of the amino acids, similar to RNA binding to Tat or polyArg.
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Affiliation(s)
- Ying Cai
- Department of Biomedical Engineering, The Vontz Center for Molecular Studies, College of Engineering and College of Medicine, University of Cincinnati, Cincinnati, Ohio 45267, USA
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30
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Kitamura A, Jardine PJ, Anderson DL, Grimes S, Matsuo H. Analysis of intermolecular base pair formation of prohead RNA of the phage phi29 DNA packaging motor using NMR spectroscopy. Nucleic Acids Res 2007; 36:839-48. [PMID: 18084020 PMCID: PMC2241910 DOI: 10.1093/nar/gkm874] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
The bacteriophage ø29 DNA packaging motor that assembles on the precursor capsid (prohead) contains an essential 174-nt structural RNA (pRNA) that forms multimers. To determine the structural features of the CE- and D-loops believed to be involved in multimerization of pRNA, 35- and 19-nt RNA molecules containing the CE-loop or the D-loop, respectively, were produced and shown to form a heterodimer in a Mg2+-dependent manner, similar to that with full-length pRNA. It has been hypothesized that four intermolecular base pairs are formed between pRNA molecules. Our NMR study of the heterodimer, for the first time, proved directly the existence of two intermolecular Watson–Crick G–C base pairs. The two potential intermolecular A–U base pairs were not observed. In addition, flexibility of the D-loop was found to be important since a Watson–Crick base pair introduced at the base of the D-loop disrupted the formation of the intermolecular G–C hydrogen bonds, and therefore affected heterodimerization. Introduction of this mutation into the biologically active 120-nt pRNA (U80C mutant) resulted in no detectable dimerization at ambient temperature as shown by native gel and sedimentation velocity analyses. Interestingly, this pRNA bound to prohead and packaged DNA as well as the wild-type 120-nt pRNA.
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Affiliation(s)
- Aya Kitamura
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, USA
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Abstract
While capsid proteins are assembled around single-stranded genomic DNA or RNA in rod-shaped viruses, the lengthy double-stranded genome of other viruses is packaged forcefully within a preformed protein shell. This entropically unfavourable DNA or RNA packaging is accomplished by an ATP-driven viral nanomotor, which is mainly composed of two components, the oligomerized channel and the packaging enzymes. This intriguing DNA or RNA packaging process has provoked interest among virologists, bacteriologists, biochemists, biophysicists, chemists, structural biologists and computational scientists alike, especially those interested in nanotechnology, nanomedicine, AAA+ family proteins, energy conversion, cell membrane transport, DNA or RNA replication and antiviral therapy. This review mainly focuses on the motors of double-stranded DNA viruses, but double-stranded RNA viral motors are also discussed due to interesting similarities. The novel and ingenious configuration of these nanomotors has inspired the development of biomimetics for nanodevices. Advances in structural and functional studies have increased our understanding of the molecular basis of biological movement to the point where we can begin thinking about possible applications of the viral DNA packaging motor in nanotechnology and medical applications.
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Affiliation(s)
- Peixuan Guo
- Department of Comparative Pathobiology and Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA.
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Shu D, Zhang H, Jin J, Guo P. Counting of six pRNAs of phi29 DNA-packaging motor with customized single-molecule dual-view system. EMBO J 2007; 26:527-37. [PMID: 17245435 PMCID: PMC1783441 DOI: 10.1038/sj.emboj.7601506] [Citation(s) in RCA: 144] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2006] [Accepted: 11/23/2006] [Indexed: 11/09/2022] Open
Abstract
Direct imaging or counting of RNA molecules has been difficult owing to its relatively low electron density for EM and insufficient resolution in AFM. Bacteriophage phi29 DNA-packaging motor is geared by a packaging RNA (pRNA) ring. Currently, whether the ring is a pentagon or hexagon is under fervent debate. We report here the assembly of a highly sensitive imaging system for direct counting of the copy number of pRNA within this 20-nm motor. Single fluorophore imaging clearly identified the quantized photobleaching steps from pRNA labeled with a single fluorophore and concluded its stoichiometry within the motor. Almost all of the motors contained six copies of pRNA before and during DNA translocation, identified by dual-color detection of the stalled intermediates of motors containing Cy3-pRNA and Cy5-DNA. The stalled motors were restarted to observe the motion of DNA packaging in real time. Heat-denaturation analysis confirmed that the stoichiometry of pRNA is the common multiple of 2 and 3. EM imaging of procapsid/pRNA complexes clearly revealed six ferritin particles that were conjugated to each pRNA ring.
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Affiliation(s)
- Dan Shu
- Department of Comparative Pathobiology and Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
| | - Hui Zhang
- Department of Comparative Pathobiology and Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
| | - Jiashun Jin
- Department of Statistics, Purdue University, West Lafayette, IN, USA
| | - Peixuan Guo
- Department of Comparative Pathobiology and Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
- Purdue Cancer Center, Hansen Life Science Research Building, Purdue University, West Lafayette, IN 47907, USA. Tel.: +1 765 494 7561; Fax: +1 765 496 1795; E-mail:
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Atz R, Ma S, Gao J, Anderson DL, Grimes S. Alanine scanning and Fe-BABE probing of the bacteriophage ø29 prohead RNA-connector interaction. J Mol Biol 2007; 369:239-48. [PMID: 17433366 PMCID: PMC1976407 DOI: 10.1016/j.jmb.2007.03.033] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2007] [Revised: 02/21/2007] [Accepted: 03/13/2007] [Indexed: 11/22/2022]
Abstract
The DNA packaging motor of the Bacillus subtilis bacteriophage ø29 prohead is comprised in part of an oligomeric ring of 174 base RNA molecules (pRNA) positioned near the N termini of subunits of the dodecameric head-tail connector. Deletion and alanine substitution mutants in the connector protein (gp10) N terminus were assembled into proheads in Escherichia coli and the particles tested for pRNA binding and DNA-gp3 packaging in vitro. The basic amino acid residues RKR at positions 3-5 of the gp10 N terminus were central to pRNA binding during assembly of an active DNA packaging motor. Conjugation of iron(S)-1-(p-bromoacetamidobenzyl) ethylenediaminetetraacetate (Fe-BABE) to residue S170C in the narrow end of the connector, near the N terminus, permitted hydroxyl radical probing of bound [(32)P]pRNA and identified two discrete sites proximal to this residue: the C-helix at the junction of the A, C and D helices, and the E helix and the CE loop/D loop of the intermolecular base pairing site.
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Affiliation(s)
- Rockney Atz
- Department of Diagnostic and Biological Sciences, University of Minnesota, Minneapolis, MN 55455
| | - Shuhua Ma
- Department of Chemistry and Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, MN 55455
| | - Jiali Gao
- Department of Chemistry and Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, MN 55455
| | - Dwight L. Anderson
- Department of Diagnostic and Biological Sciences, University of Minnesota, Minneapolis, MN 55455
- Department of Microbiology, University of Minnesota, Minneapolis, MN 55455
| | - Shelley Grimes
- Department of Diagnostic and Biological Sciences, University of Minnesota, Minneapolis, MN 55455
- *To whom correspondence should be addressed at the University of Minnesota, 18-242 Moos Tower, 515 Delaware St. S. E., Minneapolis, MN 55455; Phone (612) 624-0667; FAX (612) 625-1108;
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Sun J, Cai Y, Moll WD, Guo P. Controlling bacteriophage phi29 DNA-packaging motor by addition or discharge of a peptide at N-terminus of connector protein that interacts with pRNA. Nucleic Acids Res 2006; 34:5482-90. [PMID: 17020922 PMCID: PMC1636484 DOI: 10.1093/nar/gkl701] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Bacteriophage phi29 utilizes a motor to translocate genomic DNA into a preformed procapsid. The motor contains six pRNAs, an enzyme and one 12-subunit connector with a central channel for DNA transportation. A 20-residue peptide containing a His-tag was fused to the N-terminus of the connector protein gp10. This fusion neither interfered with procapsid assembly nor affected the morphology of the prolate-shaped procapsid. However, the pRNA binding and virion assembly activity were greatly reduced. Such decreased functions can be switched back on by the removal of the tag via protease cleavage, supporting the previous finding that the N-terminus of gp10 is essential for the pRNA binding. The DNA-packaging efficiency with dimeric pRNA was more seriously affected by the extension than with monomeric pRNA. It is speculated that the fusion of the tag generated physical hindrance to pRNA binding, with greater influence for the dimers than the monomers due to their size. These results reveal a potential to turn off and turn on the motor by attaching or removing, respectively, a component to outer part of the motor, and offers an approach for the inhibition of viral replication by using a drug or a small peptide targeted to motor components.
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Affiliation(s)
- Jianhe Sun
- Department of Pathobiology, Purdue Cancer Center and Weldon School of Biomedical Engineering, Purdue UniversityWest Lafayette, IN 47907, USA
- School of Agriculture and Biology, Shanghai Jiaotong UniversityShanghai, 201101, People's Republic of China
| | - Ying Cai
- Department of Pathobiology, Purdue Cancer Center and Weldon School of Biomedical Engineering, Purdue UniversityWest Lafayette, IN 47907, USA
| | - Wulf-Dieter Moll
- Department of Pathobiology, Purdue Cancer Center and Weldon School of Biomedical Engineering, Purdue UniversityWest Lafayette, IN 47907, USA
| | - Peixuan Guo
- Department of Pathobiology, Purdue Cancer Center and Weldon School of Biomedical Engineering, Purdue UniversityWest Lafayette, IN 47907, USA
- To whom correspondence should be addressed at Purdue Cancer Center, B-36 Hansen Life Science Research Building, Purdue University, West Lafayette, IN 47907, USA. Tel: +1 765 494 7561; Fax: +1 765 496 1795;
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Lee TJ, Guo P. Interaction of gp16 with pRNA and DNA for Genome Packaging by the Motor of Bacterial Virus phi29. J Mol Biol 2006; 356:589-99. [PMID: 16376938 DOI: 10.1016/j.jmb.2005.10.045] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2005] [Revised: 10/12/2005] [Accepted: 10/17/2005] [Indexed: 11/18/2022]
Abstract
One striking feature in the assembly of linear double-stranded (ds) DNA viruses is that their genome is translocated into a preformed protein coat via a motor involving two non-structural components with certain characteristics of ATPase. In bacterial virus phi29, these two components include the protein gp16 and a packaging RNA (pRNA). The structure and function of other phi29 motor components have been well elucidated; however, studies on the role of gp16 have been seriously hampered by its hydrophobicity and self-aggregation. Such problems caused by insolubility also occur in the study of other viral DNA-packaging motors. Contradictory data have been published regarding the role and stoichiometry of gp16, which has been reported to bind every motor component, including pRNA, DNA, gp3, DNA-gp3, connector, pRNA-free procapsid, and procapsid/pRNA complex. Such conflicting data from a binding assay could be due to the self-aggregation of gp16. Our recent advance to produce soluble and highly active gp16 has enabled further studies on gp16. It was demonstrated in this report that gp16 bound to DNA non-specifically. gp16 bound to the pRNA-containing procapsid much more strongly than to the pRNA-free procapsid. The domain of pRNA for gp16 interaction was the 5'/3' paired helical region. The C18C19A20 bulge that is essential for DNA packaging was found to be dispensable for gp16 binding. This result confirms the published model that pRNA binds to the procapsid with its central domain and extends its 5'/3' DNA-packaging domain for gp16 binding. It suggests that gp16 serves as a linkage between pRNA and DNA, and as an essential DNA-contacting component during DNA translocation. The data also imply that, with the exception of the C18C19A20 bulge, the main role of the 5'/3' helical double-stranded region of pRNA is not for procapsid binding but for binding to gp16.
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Affiliation(s)
- Tae-Jin Lee
- Department of Pathobiology, Weldon School of Biomedical Engineering, and Cancer Center, Purdue University, West Lafayette, IN 47907, USA
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