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Sabatucci A, D'Addario C. Bioinformatics of the Endocannabinoid System: Study of DNA Methylation at Rat Cnr1 Gene Promoter. Methods Mol Biol 2023; 2576:361-371. [PMID: 36152202 DOI: 10.1007/978-1-0716-2728-0_30] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
In this chapter, we will describe the bioinformatic tools that allow verifying the presence of CpG islands in a gene promoter region. We will also describe the tools needed to identify consensus motifs for specific transcription factors, focusing on the study of rat type-1 cannabinoid receptor gene (R_Cnr1) as a case study.
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Affiliation(s)
- Annalaura Sabatucci
- Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, Teramo, Italy.
| | - Claudio D'Addario
- Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, Teramo, Italy
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2
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Chen J, Wu X, Wang Y, Pan Y, Ren Y, Nakabeppu Y, Fan Y, Wang Y. Mutyh deficiency downregulates mitochondrial fusion proteins and causes cardiac dysfunction via α-ketoglutaric acid reduction with oxidative stress. Free Radic Res 2022; 56:129-142. [DOI: 10.1080/10715762.2022.2036336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- Jingwen Chen
- Department of Medical Genetics, Nanjing University School of Medicine, Nanjing 210093, China
- Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing 210093, China
| | - Xin Wu
- Department of Medical Genetics, Nanjing University School of Medicine, Nanjing 210093, China
- Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing 210093, China
| | - Yanyi Wang
- Department of Medical Genetics, Nanjing University School of Medicine, Nanjing 210093, China
- Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing 210093, China
| | - Yunfeng Pan
- Department of Medical Genetics, Nanjing University School of Medicine, Nanjing 210093, China
- Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing 210093, China
| | - Yan Ren
- Department of Medical Genetics, Nanjing University School of Medicine, Nanjing 210093, China
- Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing 210093, China
| | - Yusaku Nakabeppu
- Division of Neurofunctional Genomics, Department of Immunobiology and Neuroscience, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Yimei Fan
- Department of Medical Genetics, Nanjing University School of Medicine, Nanjing 210093, China
- Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing 210093, China
| | - Yaping Wang
- Department of Medical Genetics, Nanjing University School of Medicine, Nanjing 210093, China
- Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing 210093, China
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3
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Perera EM, Bao Y, Kos L, Berkovitz G. Structural and functional characterization of the mouse tescalcin promoter. Gene 2010; 464:50-62. [PMID: 20540995 DOI: 10.1016/j.gene.2010.06.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2010] [Revised: 06/01/2010] [Accepted: 06/02/2010] [Indexed: 02/06/2023]
Abstract
Tescalcin, an EF-hand calcium binding protein that regulates the Na(+)/H(+) exchanger 1 (NHE1), is highly expressed in various mouse tissues such as heart and brain. Despite its potentially important role in cell physiology, the mechanisms that regulate tescalcin gene (Tesc) expression are unknown. In this study, we report two new Tesc mRNA variants (V2 and V3) and characterize the mouse Tesc promoter. The V2 and V3 transcripts result from alternative splicing of intron 5. Our results show that Tesc mRNA variants are expressed in various mouse tissues. Primer extension analysis located the transcription start site at 94 nucleotides upstream of the translation start codon. The DNA nucleotide sequence of the 5'-flanking region contained a CpG island spanning the promoter region from nucleotides -372 to +814, a canonical TATA box (-38/-32), and putative transcription factor binding sites for Sp1, EGR1, ZBP-89, KLF3, MZF1, AP2, ZF5, and CDF-1. Transient transfection of the Y1 and msc-1 cell lines with a series of 5'-deleted promoter constructs indicated that the minimal promoter region was between nucleotides -130 and -40. Electrophoresis mobility shift assays, supershift assays, and mutation studies demonstrated that Sp1 and Sp3 bind to the GC-rich motifs, a CACCC box and three GC boxes, located within the Tesc proximal promoter. Nonetheless, mutations that abolished interaction of Sp1 and Sp3 with the GC-rich motifs located within the minimal promoter region did not abrogate promoter activity in Y1 cells. Mithramycin A, an inhibitor of Sp1-DNA interaction, reduced Tesc promoter activity in msc-1 cells in a dose-dependent manner. Sp3 was a weaker transactivator compared to Sp1 in Drosophila D.mel-2 cells. However, when Sp1 and Sp3 were coexpressed, they transactivated the Tesc promoter in a synergistic manner. In Y1 cells, mutation analysis of a putative ZF5 motif located within the Tesc minimal promoter indicated that this motif was critical for activity of Tesc promoter. Taken together, the data demonstrated that Sp1 and Sp3 transcription factors cooperate positively in the regulation of Tesc promoter, and that the putative ZF5 motif is critical for its activation.
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Affiliation(s)
- Erasmo M Perera
- Department of Pediatrics, Endocrinology Division, University of Miami, Leonard Miller School of Medicine, Miami, FL 33136, USA.
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Sleumer MC, Mah AK, Baillie DL, Jones SJM. Conserved elements associated with ribosomal genes and their trans-splice acceptor sites in Caenorhabditis elegans. Nucleic Acids Res 2010; 38:2990-3004. [PMID: 20100800 PMCID: PMC2875031 DOI: 10.1093/nar/gkq003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The recent publication of the Caenorhabditis elegans cisRED database has provided an extensive catalog of upstream elements that are conserved between nematode genomes. We have performed a secondary analysis to determine which subsequences of the cisRED motifs are found in multiple locations throughout the C. elegans genome. We used the word-counting motif discovery algorithm DME to form the motifs into groups based on sequence similarity. We then examined the genes associated with each motif group using DAVID and Ontologizer to determine which groups are associated with genes that also have significant functional associations in the Gene Ontology and other gene annotation sources. Of the 3265 motif groups formed, 612 (19%) had significant functional associations with respect to GO terms. Eight of the first 20 motif groups based on frequent dodecamers among the cisRED motif sequences were specifically associated with ribosomal protein genes; two of these were similar to mouse EBP-45, rat HNF3-family and Drosophila Zeste transcription factor binding sites. Additionally, seven motif groups were extensions of the canonical C. elegans trans-splice acceptor site. One motif group was tested for regulatory function in a series of green fluorescent protein expression experiments and was shown to be involved in pharyngeal expression.
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Affiliation(s)
- Monica C Sleumer
- Canada's Michael Smith Genome Sciences Centre, BC Cancer Agency, 570 W 7th Ave Suite 100, Vancouver, BC, Canada
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5
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Abstract
The nonpathogenic human adeno-associated virus type 2 (AAV-2) has adopted a unique mechanism to site-specifically integrate its genome into the human MBS85 gene, which is embedded in AAVS1 on chromosome 19. The fact that AAV has evolved to integrate into this ubiquitously transcribed region and that the chromosomal motifs required for integration are located a few nucleotides upstream of the translation initiation start codon of MBS85 suggests that the transcriptional activity of MBS85 might influence site-specific integration and thus might be involved in the evolution of this mechanism. In order to begin addressing this question, we initiated the characterization of the human MBS85 promoter region and compared its transcriptional activity to that of the AAV-2 p5 promoter. Our results clearly indicate that AAVS1 is defined by a complex transcriptional environment and that the MBS85 promoter shares key regulatory elements with the viral p5 promoter. Furthermore, we provide evidence for bidirectional MBS85 promoter activity and demonstrate that the minimal motifs required for AAV site-specific integration are present in the 5' untranslated region of the gene and play a posttranscriptional role in the regulation of MBS85 expression. These findings should provide a framework to further elucidate the complex interactions between the virus and its cellular host in this unique pathway to latency.
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Shows KH, Shiang R. Regulation of the mouse Treacher Collins syndrome homolog (Tcof1) promoter through differential repression of constitutive expression. DNA Cell Biol 2008; 27:589-600. [PMID: 18771418 PMCID: PMC2925028 DOI: 10.1089/dna.2008.0766] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2008] [Revised: 06/12/2008] [Accepted: 07/01/2008] [Indexed: 01/15/2023] Open
Abstract
Treacher Collins syndrome is an autosomal-dominant mandibulofacial dysostosis caused by haploinsufficiency of the TCOF1 gene product treacle. Mouse Tcof1 protein is approximately 61% identical and 71% similar to treacle, and heterozygous knockout of Tcof1 causes craniofacial malformation. Tcof1 expression is high in developing neural crest, but much lower in other tissues. To investigate this dual regulation, highly conserved regions upstream of TCOF1 homologs were tested through deletion and mutation reporter assays, and conserved predicted transcription factor binding sites were assessed through chromatin binding studies. Assays were performed in mouse P19 embryonic carcinoma cells and in HEK293 cells to determine differential activation in cell types at different stages of differentiation. Binding of Cebpb, Zfp161, and Sp1 transcription factors was specific to the Tcof1 regulatory region in P19 cells. The Zfp161 binding site demonstrated P19 cell-specific repression, while the Sp1/Sp3 candidate site demonstrated HEK293 cell-specific activation. Moreover, presence of c-myb and Zfp161 transcripts was specific to P19 cells. A minimal promoter fragment from -253 to +43 bp directs constitutive expression in both cell types, and dual regulation of Tcof1 appears to be through differential repression of this minimal promoter. The CpG island at the transcription start site remains unmethylated in P19 cells, 11.5 dpc mouse embryonic tissue, and adult mouse ear, which supports constitutive activation of the Tcof1 promoter.
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Affiliation(s)
- Kathryn H Shows
- Department of Human and Molecular Genetics, Virginia Commonwealth University School of Medicine, Richmond, Virginia 23298-0033, USA.
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Orlov SV, Kuteykin-Teplyakov KB, Ignatovich IA, Dizhe EB, Mirgorodskaya OA, Grishin AV, Guzhova OB, Prokhortchouk EB, Guliy PV, Perevozchikov AP. Novel repressor of the human FMR1 gene - identification of p56 human (GCC)(n)-binding protein as a Krüppel-like transcription factor ZF5. FEBS J 2007; 274:4848-62. [PMID: 17714511 DOI: 10.1111/j.1742-4658.2007.06006.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A series of relatively short (GCC)(n) triplet repeats (n = 3-30) located within regulatory regions of many mammalian genes may be considered as putative cis-acting transcriptional elements (GCC-elements). Fragile X-mental retardation syndrome is caused by an expansion of (GCC)(n) triplet repeats within the 5'-untranslated region of the human fragile X-mental retardation 1 (FMR1) gene. The present study aimed to characterize a novel human (GCC)(n)-binding protein and investigate its possible role in the regulation of the FMR1 gene. A novel human (GCC)(n)-binding protein, p56, was isolated and identified as a Krüppel-like transcription factor, ZF5, by MALDI-TOF analysis. The capacity of ZF5 to specifically interact with (GCC)(n) triplet repeats was confirmed by the electrophoretic mobility shift assay with purified recombinant ZF5 protein. In cotransfection experiments, ZF5 overexpression repressed activity of the GCC-element containing mouse ribosomal protein L32 gene promoter. Moreover, RNA interference assay results showed that endogenous ZF5 acts as a repressor of the human FMR1 gene. Thus, these data identify a new class of ZF5 targets, a subset of genes containing GCC-elements in their regulatory regions, and raise the question of whether transcription factor ZF5 is implicated in the pathogenesis of fragile X syndrome.
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Affiliation(s)
- Sergey V Orlov
- Department of Biochemistry, Institute of Experimental Medicine, Russian Academy of Medical Sciences, St Petersburg, Russia.
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Kitahashi M, Sato Y, Fujimura L, Ozeki C, Arima M, Sakamoto A, Yamamoto S, Tokuhisa T, Hatano M. Identification of the consensus DNA sequence for Nczf binding. DNA Cell Biol 2007; 26:395-401. [PMID: 17570763 DOI: 10.1089/dna.2006.0565] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The Nczf gene, which is identified as a target gene of Ncx, encodes a novel Kruppel-associated box (KRAB) zinc finger protein, which functions as a sequence-specific transcriptional repressor. We generated a fusion protein of the zinc finger domain of Nczf and glutathione S-transferase to identify Nczf-binding consensus DNA sequences with random oligonucleotides of 15 and 35 bases. The consensus binding sequence of core nucleotides contains (A/T/C)CTTT(A/G)TTNT. In a gel mobility shift assay, the probe containing these sequences bound to the fusion protein. In silico analysis, these consensus sequences were found on regulatory regions of the endothelin receptor B and the microphthalmia-associated transcription factor genes, which are involved in neural crest development. These results suggest that Nczf functions as a sequence-specific transcription repressor to regulate neural crest cell development.
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Affiliation(s)
- Masayasu Kitahashi
- Department of Developmental Genetics, Graduate School of Medicine, Chiba University, Chiba, Japan
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Wang J, Kudoh J, Takayanagi A, Shimizu N. Novel human BTB/POZ domain-containing zinc finger protein ZNF295 is directly associated with ZFP161. Biochem Biophys Res Commun 2005; 327:615-27. [PMID: 15629158 DOI: 10.1016/j.bbrc.2004.12.048] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2004] [Indexed: 10/26/2022]
Abstract
Human ZNF295 protein harbors a BTB/POZ domain and multiple krüppel (C(2)H(2)) type zinc finger domains, and thus belongs to a family of POK (POZ and krüppel) transcription factor. We have identified many transcript variants generated by the alternative splicing in 5' non-coding exons, an intra-exonic splicing in a coding region, and the use of three polyadenylation signals in the 3' UTR. The intra-exonic splicing removes 603-bp coding sequence, and thus ZNF295 gene produces two protein isoforms: ZNF295L with 1066 amino acid residues and ZNF295S with 865 amino acid residues, containing 9 and 5 zinc finger domains, respectively. ZNF295 is ubiquitously expressed in human fetal and adult tissues. Analysis of transcription activity of ZNF295 using various promoter-reporters demonstrated that ZNF295 acts as a transcription repressor, and contains two separate regions for repression activity: the BTB/POZ domain and the central region between BTB/POZ and ZF domains. Both ZNF295L and ZNF295S could interact not only with themselves and each other, but also with another POK protein ZFP161 known to function as a transcription repressor and an activator. We postulated that ZNF295 may be involved in the bi-directional control of gene expression in concert with ZFP161.
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Affiliation(s)
- Jun Wang
- Department of Molecular Biology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
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Hamilton AT, Huntley S, Kim J, Branscomb E, Stubbs L. Lineage-specific expansion of KRAB zinc-finger transcription factor genes: implications for the evolution of vertebrate regulatory networks. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2004; 68:131-40. [PMID: 15338611 DOI: 10.1101/sqb.2003.68.131] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- A T Hamilton
- Genome Biology Division, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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11
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Liu X, Tiwari RK, Geliebter J, Wu JM, Godfrey HP. Interaction of a Mycobacterium tuberculosis repetitive DNA sequence with eukaryotic proteins. Biochem Biophys Res Commun 2004; 320:966-72. [PMID: 15240143 DOI: 10.1016/j.bbrc.2004.06.046] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2004] [Indexed: 11/29/2022]
Abstract
Mycobacterium tuberculosis infects one-third of the world's population and causes two million deaths annually. Its intracellular residence raises the possibility that bacterial nucleic acids might interact with key host proteins and contribute to the pathophysiology of infection. To test this hypothesis, we searched for motifs closely resembling eukaryotic transcription factor binding sites in the M. tuberculosis H37Rv genome and found activator protein-2 and zinc finger protein-5 binding motifs in a 36-nucleotide repetitive mycobacterial DNA sequence (RPT1). RPT1 bound specifically to nuclear extract proteins from U937, A549, and HeLa cells in electrophoretic mobility shift assays but not to activator protein-2. Several nuclear and cytosolic proteins showing at least partial binding specificity for RPT1 were isolated from U937 and A549 cells by pull-down assays, including Ku70 (DNA-dependent protein kinase subunit) and poly(ADP-ribose) polymerase-1. RPT1 also specifically activated DNA-dependent protein phosphorylation. These results suggest that mycobacterial nucleic acid fragments may interact specifically with eukaryotic regulatory proteins which might contribute to bacterial life-cycle maintenance.
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Affiliation(s)
- Xinyan Liu
- Department of Pathology, New York Medical College, Valhalla, NY 10595, USA
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Lee KH, Kwak YD, Kim DH, Chang MY, Lee YS, Lee YS. Human zinc finger protein 161, a novel transcriptional activator of the dopamine transporter. Biochem Biophys Res Commun 2004; 313:969-76. [PMID: 14706637 DOI: 10.1016/j.bbrc.2003.11.183] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The dopamine transporter (DAT) terminates dopaminergic neurotransmission via reuptake of released dopamine into presynaptic neurons. We have cloned 2.5 kb of the regulatory region upstream of human DAT (hDAT) and constructed a series of deletion mutants to test promoter activity. A comparison of promoter activity between non-neural and neuronal cell lines reveals an interesting difference in pattern. In the PC12 cell line, activity of the proximal promoter is strongly silenced by one or more unidentified elements spanning positions -395 to -2465 of the hDAT gene. Our studies focus on identifying and characterizing the activating factor for hDAT transcription in the sequence between -2511 and -2492 (5(')-CTA CCT GCA CAG TTC ACG GA-3('), termed HY1). In this investigation, we cloned the zinc finger protein 161 (ZFP161) gene as a HY1-binding factor, using the yeast one-hybrid screen. Recombinant ZFP161 was produced to evaluate the DNA-binding properties of the protein. The ability of ZFP161 to directly bind HY1 was examined in an electrophoretic mobility shift assay. RT-PCR analyses revealed that transfection of ZFP161 induced hDAT mRNA expression in HEK293 cells. We additionally confirmed the expression and localization of the DAT protein, using a specific antibody. Both the HY1 sequence and the downstream region were necessary for activation of the hDAT promoter by ZFP161. This finding suggests that the site of cofactor interaction with ZFP161 may exist downstream of HY1.
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Affiliation(s)
- Ki-Hwan Lee
- Department of Biochemistry, College of Medicine, Hanyang University, Seoul, Republic of Korea
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Mascle X, Albagli O, Lemercier C. Point mutations in BCL6 DNA-binding domain reveal distinct roles for the six zinc fingers. Biochem Biophys Res Commun 2003; 300:391-6. [PMID: 12504096 DOI: 10.1016/s0006-291x(02)02873-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The B-cell lymphoma 6 (BCL6) gene encodes a transcriptional repressor containing six C-terminal Krüppel-like zinc fingers. The zinc finger (ZF) cluster is necessary and sufficient for interaction with both DNA and several proteins and for nuclear targeting. However, the functional specificity of the six ZFs in these cellular roles is unknown. To characterize this domain, we mutated individually each ZF of BCL6. Our results reveal that mutation of the two N-terminal ZFs does not impair cognate DNA-binding, cellular localization of the protein nor the transcriptional repression capacity of BCL6. By contrast, mutation of any of the remaining ZFs abolishes the binding of BCL6 to DNA in vitro and the transrepressive function of the protein in vivo. Finally, none of the six mutations affect the interaction between BCL6 and class II histone deacetylases. Thus our experiments demonstrate that BCL6 uses each of the four C-terminus ZFs for binding to a target sequence while the two amino terminal fingers are likely engaged in other unknown function(s).
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Affiliation(s)
- Xavier Mascle
- INSERM U309, Institut Albert Bonniot, Domaine de la Merci, 38706 La Tronche Cedex, France
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Cathomen T, Stracker TH, Gilbert LB, Weitzman MD. A genetic screen identifies a cellular regulator of adeno-associated virus. Proc Natl Acad Sci U S A 2001; 98:14991-6. [PMID: 11734633 PMCID: PMC64971 DOI: 10.1073/pnas.261567198] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Adeno-associated virus type 2 (AAV2) is a human parvovirus that has attracted attention as a vector for gene transfer. Replication and site-specific integration of the wild-type virus requires binding of the AAV2 Rep proteins to a cis-regulatory element named the Rep recognition sequence (RRS). RRS motifs are found within the cellular AAVS1 integration locus, the viral p5 promoter, and the inverted terminal repeats (ITRs). Here we report the design of a genetic screen based on the yeast one-hybrid assay to identify cellular RRS-binding proteins. We show that the human zinc finger 5 protein (ZF5) binds specifically to RRS motifs in vitro and in vivo. ZF5 is a highly conserved and ubiquitously expressed transcription factor that contains five C-terminal zinc fingers and an N-terminal POZ domain. Ectopic expression of ZF5 leads to an ITR-dependent repression of the autologous p5 promoter and reduces both AAV2 replication and the production of recombinant AAV2. By using deletion and substitution mutants we show that two different domains of ZF5 contribute to AAV2 repression. Negative regulation of the p5 promoter requires the POZ domain, whereas viral replication is inhibited by the zinc finger domain, likely by competing with Rep for binding to the ITR. Identification and characterization of proteins that bind the ITR, the only viral genetic element retained in AAV2 vectors, will lead to new insights into the unique life cycle of AAV2 and will suggest improvements important for its application as a gene therapy vector.
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Affiliation(s)
- T Cathomen
- Laboratory of Genetics, The Salk Institute for Biological Studies, North Torrey Pines Road, La Jolla, CA 92037, USA
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