CHEMICAL BIOLOGY

Synthetic transcription elongationfactors license transcription acrossrepressive chromatinGraham S. Erwin,1* Matthew P. Grieshop,1* Asfa Ali,1* Jun Qi,2 Matthew Lawlor,2

Deepak Kumar,3,4 Istaq Ahmad,3,4 Anna McNally,5 Natalia Teider,5 Katie Worringer,5

Rajeev Sivasankaran,5 Deeba N. Syed,6 Asuka Eguchi,1 Md. Ashraf,1 Justin Jeffery,7

Mousheng Xu,2 Paul M. C. Park,2 Hasan Mukhtar,6 Achal K. Srivastava,3

Mohammed Faruq,4 James E. Bradner,2,5 Aseem Z. Ansari1,8†

The release of paused RNA polymerase II into productive elongation is highly regulated,especially at genes that affect human development and disease.To exert control over thisrate-limiting step, we designed sequence-specific synthetic transcription elongation factors(Syn-TEFs).These molecules are composed of programmable DNA-binding ligands flexiblytethered to a small molecule that engages the transcription elongation machinery. By limitingactivity to targeted loci, Syn-TEFs convert constituent modules from broad-spectrum inhibitorsof transcription into gene-specific stimulators. Here we present Syn-TEF1, a molecule thatactively enables transcription across repressive GAA repeats that silence frataxin expressionin Friedreich’s ataxia, a terminal neurodegenerative disease with no effective therapy.Themodular design of Syn-TEF1 defines a general framework for developing a class of moleculesthat license transcription elongation at targeted genomic loci.

Along-standing challenge at the interfaceof chemistry, biology, and precision med-icine is to develop molecules that can beprogrammed to regulate the expression oftargeted genes (1). It is increasingly evi-

dent that RNA polymerase II (Pol II) pausesduring transcription (2, 3). Regulated releasefrom the paused state into productive elongationis emerging as a critical step in gene expression.The number of diseases associatedwith proteinsthat play a role in implementing the pause orsubsequent release into productive elongationis rapidly growing (4–6). Given this context, wefocused on creating molecules that enable Pol IIto surmount barriers to productive elongation attargeted genomic loci. At their core, these syn-thetic transcription elongation factors (Syn-TEFs)incorporate two distinct chemicalmoieties: (i) pro-grammable DNA binders that target desired ge-nomic loci and (ii) ligands that engage thetranscription elongation machinery.Pyrrole- and imidazole-based polyamides have

emerged as a class of synthetic molecules thatcan be programmed to bind specific DNA se-quences by using well-defined molecular rec-ognition rules (7, 8). Recent examination of thegenome-wide distribution of two polyamides de-signed to target different sequences revealedthat these molecules are primarily enriched atgenomic loci bearing clusters of binding sites (9).A “summation of sites” (SOS) model integratingthe affinity of a given polyamide for all potentialbinding sites that occur within a ~400–basepair window best encapsulated the genome-widebinding preferences (9). Consistent with the SOSmodel, a polyamide previously designed to targeta AAGAAGAAG site is enriched at repressiveGAA microsatellite repeats within the first intron

of frataxin (FXN) in a cell line derived from aFriedreich’s ataxia (FRDA) patient (10).In FRDA cells, expanded GAA repeats are en-

riched in repressive histone marks and can alsoadopt uncommon DNA conformations that im-pede transcription (11, 12). The number of re-peats positively correlates with both the extentof repression and the severity of disease (13, 14).The prevailing models in the field are that re-pressive chromatin and/or unusual DNA con-formations present a barrier to the productiveelongation of the FXN transcripts (11, 12, 15–18).Efforts to reverse repressive chromatin markswith freely diffusing histone deacetylase inhib-itors or the use of a polyamide intended to driveuncommon structures toward canonical B-formDNA conformation did not elicit sufficient FXNexpression (10, 19). Therefore, we reasoned that asynthetic molecule capable of binding repressiveGAA repeats and actively assisting productiveelongation would restore FXN expression to levelsobserved in normal cells. A pivotal step in the tran-sition of a paused Pol II into productive elongationis the recruitment of the positive transcriptionelongation factor b (P-TEFb). This complex containsthe cyclin-dependent kinase 9 (CDK9),whichphos-phorylates multiple proteins, including Pol II, tofacilitate transcription elongation (2, 5, 20).To avoid perturbing CDK9 kinase activity, we

focused on ligands of BRD4, a protein that bindsacetylated histones and engages active P-TEFbat transcribed genes (20). Among BRD4 ligands,JQ1 has been extensively characterized and shownto competitively displace BRD4 from regulatoryregions of the genome (21). JQ1 therefore func-tions as a broad-spectrum inhibitor of oncogene-stimulated transcription, and a chemical deriv-ative is now in clinical trials (21). On the basis

of its mechanism of action, we reasoned thattethering JQ1 to specific genomic loci would miti-gate its global inhibitory properties and con-vert this molecule into a locus-specific stimulatorof transcription. Moreover, rather than stimulat-ing transcription initiation, we reasoned thatJQ1-dependent recruitment of the elongationmachinery across the length of the repressiveGAA repeats would enable Pol II to actively over-come the barrier to transcriptional elongationacross the silenced FXN gene.To design bifunctional Syn-TEFs, we examined

the crystal structures of the polyamide-nucleosomecomplex and the JQ1-BRD4 bromodomain com-plex and identified optimal sites for chemicalconjugation (Fig. 1A) (21, 22). Polyamides PA1 andPA2 were conjugated to JQ1 to generate Syn-TEF1 and Syn-TEF2, respectively (Fig. 1B, figs.S1 and S2, and table S1) (10, 23). Genome-widebinding profiles confirm that the linear poly-amide PA1 binds GAA repeats, whereas the hair-pin polyamide PA2 targets an unrelated sequence(9). The ability of Syn-TEFs to stimulate expressionof endogenous FXN was examined in GM15850cells, a FRDA patient-derived cell line (Fig. 1C). Inthis lymphoblastoid cell line, FXN levels are re-duced by ~90% compared with GM15851 cellsfrom the patient’s healthy sibling (Fig. 1C andfig. S4). In a dose-dependent manner, Syn-TEF1restored FXN expression in FRDA cells to thelevels observed inhealthy cells (Fig. 1C and fig. S5B).Syn-TEF2, which does not target GAA repeats,did not activate FXN expression in either cell line,demonstrating the requirement for sequence-specific DNA targeting (Fig. 1C). FXN transcriptsthat are induced by Syn-TEF1 function were splicedand translated to levels comparable to those inhealthy cells (Fig. 1D).To determine the specificity of action in the

context of the entire transcriptome, we performedRNA sequencing (RNA-seq) in GM15850 andGM15851 cells (Fig. 1E, fig. S6, and tables S9 toS16). FXN was the transcript most significantlystimulated by Syn-TEF1 in the diseased cell line.The global transcriptome was minimally per-turbed, with 11 genes differentially expressed bymore than twofold (Fig. 1E and tables S9 andS23). Milder Syn-TEF1–dependent perturbationsoccurred for an additional 225 genes, of whichasmany as 29 coincidewith knownFRDAexpres-sion networks (table S24) (24). Parallel treatmentof the control GM15851 cells did not alter FXN

RESEARCH

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1Department of Biochemistry, University of Wisconsin–Madison, Madison, WI 53706, USA. 2Department of MedicalOncology, Dana-Farber Cancer Institute, Boston, MA 02215,USA. 3Department of Neurology, All India Institute of MedicalSciences, New Delhi, India. 4Genomics and MolecularMedicine, Council of Scientific and Industrial Research(CSIR)–Institute of Genomics and Integrative Biology (IGIB),New Delhi, India. 5Novartis Institutes for BioMedicalResearch (NIBR), Cambridge, MA 02139, USA. 6Departmentof Dermatology, University of Wisconsin–Madison, Madison,WI 53706, USA. 7Small Animal Imaging Facility, University ofWisconsin Carbone Cancer Center, Madison, WI 53792, USA.8The Genome Center of Wisconsin, University of Wisconsin–Madison, Madison, WI 53706, USA.*These authors contributed equally to this work.†Corresponding author. Email: azansari@wisc.edu

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expression and elicited a comparably muted ef-fect on the global transcriptome (Fig. 1E andtable S10). This result starkly contrasts with thefinding of 4091 genes whose levels were signif-icantly perturbed by freely diffusing JQ1 (fig. S6Eand table S11). Consistent with its antiprolifer-ative properties (21), freely diffusing JQ1 down-regulates expression of the oncogene c-MYC.Because Syn-TEF1 targets JQ1 to specific genomicloci away from c-MYC, no change in c-MYC ex-pression was observed in cells treated with thisbifunctional molecule (Fig. 1E).To determine whether Syn-TEF1 stimulates

FXN by engaging the endogenous elongationmachinery, we performed genome-wide chro-

matin immunoprecipitation analysis of BRD4,Pol II, and elongation-specific phosphorylatedserine 2 (phospho-Ser2) marks on the largestsubunit of Pol II. Given that polyamides bind toclustered sites in heterochromatin (9), we ex-pected that Syn-TEF1 would localize to the firstintron of FXN in disease cells that contain theGAA-repeat expansion, but not in healthy cells(Fig. 2A and fig. S7). Consistent with the SOSprofile of Syn-TEF1 binding, BRD4 levels weremarkedly increased across the GAA-repeat ex-pansion in FRDA cells (Fig. 2B). Because currentalgorithms remove sequencing reads that mapto identical GAA repeats, the unannotated region(650 GAA repeats shown) is represented by a gap

colored in blue in Fig. 2, A to D. Perhaps morestriking is the profile of phospho-Ser2 marksplaced on the productively elongating RNA Pol II(Fig. 2C and table S7). The peak of phospho-Ser2enrichment is offset downstream of the BRD4peaks, consistent with sequential action ofP-TEFb and subsequent licensing of Pol II forproductive transcription elongation. Owing tothe mechanistic coupling of transcriptional pro-cesses, phospho-Ser2 marks were retained untiltermination, well beyond the point of BRD4 re-cruitment by Syn-TEF1 (Fig. 2, B and C). Un-expectedly, a promoter-proximal BRD4 peakoverlapped with the paused Pol II upstreamof the GAA repeats (Fig. 2D and fig. S8). Upon

Erwin et al., Science 358, 1617–1622 (2017) 15 December 2017 2 of 5

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Fig. 1. Synthetic transcription elongation factors (Syn-TEFs) selectivelyactivate FXN expression. (A) Co-crystal structures of JQ1 bound to BRD4[Protein Data Bank (PDB) ID, 3MXF] and polyamide bound to nucleosomalDNA (PDB ID, 1M1A). The distance allowing interaction of these complexes isestimated. (B) Linear PA1 and Syn-TEF1 target the DNA sequence 5′-AAGAAGAAG-3′. Hairpin PA2 and Syn-TEF2 target 5′-WTACGTW-3′, whereW is A or T. The structures of N-methylpyrrole (open circles), N-methylimidazole (filled circles), 3-chlorothiophene (squares), and b-alanine(diamonds) are shown. N-methylimidazole is bolded for clarity. The structureof JQ1 linked to polyethylene glycol (PEG6) is represented as a blue circle.The asterisk indicates the site where the R group attaches to the polyamide.(C) Relative expression of FXNmRNA in GM15850 (left) and GM15851 (right)

cell lines by quantitative reverse transcription polymerase chain reaction.Results are means ± SEM (n = 4), normalized to the relative expression ofFXN in GM15851 cells (fig. S4). All treatments were 24 hours with 1 mM ofthe indicated molecule, except dimethyl sulfoxide (DMSO, represented bythe dash; 0.1%) and Syn-TEF1 (0.1, 0.5, or 1 mM). *P < 0.05; **P < 0.01.(D) Immunoblot of FXN and a-tubulin (TUB) with treated GM15850 (left)and GM15851 (right) cells. Cells were treated as in (C). (E) Volcano plots ofRNA-seq data display the change in global gene expression after 24 hoursof treatment of GM15850 (left) and GM15851 (right) cells with 1 mM Syn-TEF1(n = 4). Values represent the posterior probability of equal expression (PPEE)versus fold change in expression normalized to DMSO-treated samples(n = 4). FXN and c-MYC are labeled in red and blue, respectively.

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Fig. 2. Syn-TEF1 recruits BRD4 to its targetsites and licenses productivePol II elongation at FXN. All dataare from GM15850 cells treated for24 hours with the indicated molecules.Signal traces are in reference-adjustedreads per million reads per base pair(rrpm/bp). (A) Summation of sites (SOS)profile of PA1 and Syn-TEF1 across theFXN locus. (B) BRD4 occupancy at the FXNlocus. (C) Occupancy by phosphorylatedserine 2 (phospho-Ser2) of the C-terminaldomain of RNA Pol II at the FXN locus.(D) Occupancy of RNA Pol II at the 5′ regionof FXN. The gray bar identifies the locationof the repressive GAA repeats, and cyanregions highlight unannotated reads but donot have defined quantitative values.(E) Occupancy of H3K4me3 and H3K36me3measured at several locations within theFXN locus. Results are means ± SEM(n = 3). (F) A model of the cascadeof interactions and reactions initiated bySyn-TEF1 at FXN. CTD, C-terminaldomain; S2P, phospho-Ser2. p

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200Fig. 3. Syn-TEF1 recruits BRD4 to its targetsites and selectively activates FXN. All dataare from GM15850 cells treated for 24 hourswith the indicated molecules (1 mM). (A) Heatmapof the SOS profile of Syn-TEF1 across the top250 predicted binding sites of PA1 (9, 31).(B) Heatmaps of BRD4, Pol II, and phospho-Ser2occupancy across the same genomic loci asin (A). kb, kilobases. (C) Occupancy of BRD4 atBRD4 binding sites across the genome aftertreatment with Syn-TEF1 or PA1 and JQ1. ChIP,chromatin immunoprecipitation. (D) Scatterplotof SOS score versus distance of the predictedSyn-TEF1 binding site to the transcription start site (TSS) for the top 500 genes predicted to be targeted by Syn-TEF1. Each gene is shadedaccording to the change in gene expression after Syn-TEF1 treatment. (E) Scatterplot of the SOS score, change in gene expression (after Syn-TEF1treatment), and licensing ratio (LR) of RNA Pol II for the top 500 genes predicted to be targeted by Syn-TEF1. FC, fold change.

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treatment with Syn-TEF1, the decrease in pausedPol II coincided with the increase in Pol II levelswithin the body of FXN, thus furnishing evidencefor licensing of productive elongation (Fig. 2Dand table S6). Furthermore, trimethylation oflysine 36 of histone H3 (H3K36me3), a signatureof productive elongation, increased downstreamof the GAA repeats in Syn-TEF1–treated cells(Fig. 2E). In support of enhanced elongation, adownstream shift in trimethylation of lysine 4of histone H3 (H3K4me3), a promoter-proximalchromatin mark, was also observed (Fig. 2E). Inagreement with previous reports, we did not ob-

serve a dramatic increase in H3K4me3 marks atthe promoter upon Syn-TEF1 treatment (11, 16).Consistent with a barrier to elongation, tetheringproteins that stimulate transcriptional initiationfailed to enhance FXN expression, whereas teth-ering VP16 or derivatives that can stimulateelongation elicited modest FXN expression (25).As our results demonstrate, targeted recruitmentof an elongation factor across the GAA repeatsrestores FXN expression in FRDA cells.To further investigate the specificity of Syn-

TEF1, we examined the enrichment of BRD4,Pol II, and phospho-Ser2 at Syn-TEF1–targeted

genomic loci. These loci were rank-ordered bytheir affinity for Syn-TEF1 (Fig. 3A and table S22).Whereas the BRD4 enrichment profile correlatedwith the polyamide binding profile (compareFig. 3, A and B), neither phospho-Ser2 nor Pol IIshowed any enrichment over a 10,000–base pairwindow centered on the polyamide-targetedgenomic loci (Fig. 3B and fig. S10). Moreover,genome-wide binding of BRD4 was not per-turbed by Syn-TEF1, whereas freely diffusing JQ1markedly reduced BRD4 occupancy en masse(Fig. 3C and fig. S10B). This observation is con-gruent with the minimal impact of Syn-TEF1 on

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Fig. 4. Syn-TEFs activate FXN expression inprimary patient cells and patient-derivedfibroblasts, iPSCs, cardiomyocytes, sensoryneurons, and mouse xenografts. All treatmentswere 24 hours, except where specified. (A) Relativeexpression of FXN mRNA, normalized to GAPDHin three lymphoblastoid cell lines derived fromthree different FRDA patients. All treatments were1 mM (means ± SEM; n = 3). *P <0.05; **P < 0.01.(B) Expression of cell type–specific markers inGM23913 iPSCs or iPSC-derived cardiomyocytesafter treatment with 0.1% DMSO (means; n = 2).(C) Syn-TEF1–dependent induction of FXN mRNA inGM23913-derived cardiomyocytes (60 hours oftreatment; means; n = 2). (D) Immunohistochemistryof GM23913 iPSCs and iPSC-derived cardiomyocytes.iPSCs were fixed and stained with OCT4 and SOX2.iPSC-derived cardiomyocytes were fixed and stainedwith TNNT2 and MYL2. Scale bars, 100 mm.(E) Immunoblot of FXN and b-actin (b-ACT) aftertreatment of three different primary FRDA fibroblasts,fibroblast-derived iPSCs, and sensory neurons withthe indicated molecules. Fibroblasts were collectedfrom patients UAB4259 (550/1000), UAB4230(1000/1200), and UAB66 (90/1025). Cells weretreated for 72 to 96 hours. (F) Immunohistochemistryof FRDA patient–derived iPSCs and iPSC-derivedsensory neurons. iPSCs were fixed and stained withOCT4 and SSEA-4. Sensory neurons were fixedand stained with neuronal markers CGRP and MAP-2.Scale bars, 100 mm. (G) (i) Genotyped repeatsand (ii) relative expression of FXN mRNA normalizedto GAPDH in peripheral blood mononuclear cells(PBMCs) from 11 patients after 24 hours of treatmentwith 1 mM Syn-TEF1. (H) Bioluminescent images oftwo representative mice harboring xenografts(HEK293 FXN-Luc with six and ~310 GAA repeats inthe left and right flanks, respectively) (29). Micewere treated with either vehicle (DMSO) or 0.5 nmolSyn-TEF1 administered subcutaneously into eachtumor (1 nmol total per mouse). Mice were imaged22 hours after treatment. (I) Relative expressionof FXN-Luc with six or ~310 GAA repeats afterSyn-TEF1 treatment of mice as described in (H).Results are means ± SEM (n = 4 and 3 Syn-TEF1–treated and DMSO-treated mice, respectively). *P <0.05. (J) Aconitase activity in GM16214 lymphoblastoidcells after 72 hours of treatment with DMSO (0.1%),PA1 (125 nM), or Syn-TEF1 (62.5 or 125 nM).Aconitase activity was normalized to GM16215 cells.Results are means ± SEM (n = 3).

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global transcriptome profiles in healthy and dis-eased cells (Fig. 1E). Thus, Syn-TEF1 displaysregulatory properties distinct from those of in-hibitors of BRD4 that globally disrupt the transi-tion to transcription elongation and elicit cellcycle arrest in cancer cells (21). We next mappedSyn-TEF1–targeted genomic loci to transcriptionstart sites of proximal genes and compared SOSscores with fold change in mRNA expression(Fig. 3D). In addition to the importance of a highSOS score proximal to a TSS, the results suggestthat geneswith substantial pausing of RNAPol II[low licensing ratios (LRs)] respond to Syn-TEF1(Fig. 3E). Taken together, the results demonstratethat in the absence of paused or stalled Pol II,simply recruiting BRD4 to a genomic locus doesnot elicit transcriptional initiation. This conclu-sion is supported by a recent study that deliveredJQ1 to two endogenous promoters and enrichedBRD4 at those loci but did not find an increase intargeted gene expression from either locus (26).The dependence on pausedPol II imposesmecha-nistic constraints on the function ofDNA-tetheredJQ1, and it serves as a valuable specificity filterto limit Syn-TEF1 function toFXN, withminimalperturbation of the global transcriptome.Next, we examined the impact of Syn-TEF1

on primary cells and cell lines derived from morethan 20 FRDA patients with different geneticbackgrounds and different GAA-repeat expan-sions. In lymphoblastoid cells, fibroblasts, andinduced pluripotent stem cells (iPSCs) derivedfrom FRDA patients, Syn-TEF1 stimulated FXNexpression, whereas the control molecules ortreatments did not (Fig. 4, A to E). To examinethe ability of Syn-TEF1 to stimulate FXN expres-sion in disease-relevant cell types, we differentiatedGM23913 pluripotent cells to cardiomyocytes(27). Upon differentiation, cardiomyocytes ex-pressed cardiac-specific markers and displayedrhythmic beating in culture (Fig. 4, B and D,figs. S11 and S12, and movie S1). Syn-TEF1 ro-bustly stimulated FXN expression in these cells,whereas JQ1, with or without PA1, led to cyto-toxicity (Fig. 4C). Like cardiomyocytes, neuronsare particularly vulnerable to a reduction in FXNexpression (28). Sensory neurons derived fromthree iPSC lines (Fig. 4F and fig. S13) displayedevidence of Syn-TEF1–responsive production ofprocessed mature FXN protein (Fig. 4E). In ad-dition to cultured cells, primary peripheral bloodmononuclear cells obtained from 11 FRDA pa-tients were genotyped and treated in parallelwith Syn-TEF1. FXN expression was stimulatedby Syn-TEF1 in all but one sample from the 11FRDA patients (Fig. 4G).To examine the utility of Syn-TEF1 in re-

storing FXN levels in vivo, we transplanted hu-

man cells bearing a luciferase reporter fused inframe within the fifth exon of FXN into theflanks of immunocompromised mice (Fig. 4, Hand I). The first reporter cell line contained onlysix GAA repeats, and the second reporter cell linecontained~310GAA repeats (29). Consistentwithcell culture results (fig. S16) (29), we observedreduced FXN-Luc levels in transplanted cellsbearing ~310GAA repeats (Fig. 4, H and I). UponSyn-TEF1 treatment, luciferase expression wasstimulated in the cells with ~310 GAA repeats,nearly restoring levels to those seen in the re-porter cell line with six repeats (Fig. 4, H and I).As evidence of recovery of mitochondrial func-tion, we observed ~90% recovery of aconitaseactivity in patient-derived lymphoblastoid cellsthat were treatedwith Syn-TEF1 (Fig. 4J). Takentogether, our results showed that inmultiple celltypes from 20 FRDA patients with a broad rangeof repeat expansions and diverse genetic back-grounds, the prototype synthetic transcriptionelongation factor stimulated FXN expression andrestored biological function.Syn-TEF1 meets key design criteria, including

the ability to (i) target desired loci in the genome,(ii) access cognate sites in repressive chromatin,(iii) engage the endogenous elongation machin-ery, and (iv) license productive transcriptionalelongation by a paused Pol II. In essence, ourprototype Syn-TEF defines a general frameworkfor the design of a class of molecules that couldact on a diverse array of diseases caused by dif-ferent stages of transcriptional dysfunction, es-pecially at unstable microsatellite repeats (30).The growing mechanistic understanding of generegulation, and how it goes awry in disease, offersnew opportunities for intervention and remedia-tion with precision-tailored synthetic molecules.

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ACKNOWLEDGMENTS

We thank members of the Ansari laboratory, especially D. Bhimsaria,and members of the Raines laboratory, especially T. Smith,for helpful discussions; L. Vanderploeg and E. N. Korkmaz for helpwith figures; J. Thomson, R. Stewart, J. Bolin, and S. Swanson for helpwith RNA-seq; A. Kumar, S. Mohapatra, and D. Waseem for earlyexperiments; R. Dolmetsch and A. Kaykas for facilitating thecollaboration with the Neuroscience group at NIBR; andS. Brahmachari and A. Agarwal for facilitating the collaborationwith the Ataxia group at IGIB. The NIBR team thanks M. Napierala[University of Alabama at Birmingham (UAB)], D. Lynch [Children’sHospital of Philadelphia (CHOP)], and FARA (Friedreich’s AtaxiaResearch Alliance) for making the UAB Friedreich’s ataxia patientlines available for use. Friedreich’s ataxia patient fibroblasts andiPSC-derived sensory neurons were obtained under a materialtransfer agreement with CHOP. We thank R. Wade-Martins(University of Oxford) for the luciferase reporter cell lines. Thiswork was supported by NIH grants CA133508, GM117362, andHL099773 and a W. M. Keck Medical Research Award to A.Z.A. and byNIH grant P30 AR066524 to D.N.S. G.S.E. was supported by NIHgrant GM07215 and a Peterson Fellowship. M.P.G. was supported by aHilldale scholarship. A.A. was supported by an Indo-US PostdoctoralFellowship from the Science and Engineering Research Board ofthe Government of India. RNA-seq and ChIP-seq data are deposited inthe National Center for Biotechnology Information Gene ExpressionOmnibus under GSE99403. A.Z.A., G.S.E., and M.P.G have filed patentapplications relating to the work in this manuscript, including U.S.provisional patent applications 62/478291 and 15/472852, filed30 March 2016 by the Wisconsin Alumni Research Foundation.

SUPPLEMENTARY MATERIALS

www.sciencemag.org/content/358/6370/1617/suppl/DC1Materials and MethodsFigs. S1 to S16Tables S1 to S24References (31–44)Movie S1

12 May 2017; accepted 15 November 2017Published online 30 November 201710.1126/science.aan6414

Erwin et al., Science 358, 1617–1622 (2017) 15 December 2017 5 of 5

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Synthetic transcription elongation factors license transcription across repressive chromatin

Xu, Paul M. C. Park, Hasan Mukhtar, Achal K. Srivastava, Mohammed Faruq, James E. Bradner and Aseem Z. AnsariNatalia Teider, Katie Worringer, Rajeev Sivasankaran, Deeba N. Syed, Asuka Eguchi, Md. Ashraf, Justin Jeffery, Mousheng Graham S. Erwin, Matthew P. Grieshop, Asfa Ali, Jun Qi, Matthew Lawlor, Deepak Kumar, Istaq Ahmad, Anna McNally,

originally published online November 30, 2017DOI: 10.1126/science.aan6414 (6370), 1617-1622.358Science 

, this issue p. 1617Sciencediseases caused by unstable expansions in microsatellite repeats.

expression to normal levels. In the future, similar interventions may be effective in a diverse array ofFXNand restores specifically targets the expanded repressive repeats. This molecule thereby licenses productive transcription elongation

synthesized a molecule thatet al. gene. Erwin FXNof intronic repeats and hence a reduced expression of the Friedreich's ataxia, a devastating neurodegenerative disease with no effective therapy, is caused by an expansion

Chemical control of transcription

ARTICLE TOOLS http://science.sciencemag.org/content/358/6370/1617

MATERIALSSUPPLEMENTARY http://science.sciencemag.org/content/suppl/2017/11/29/science.aan6414.DC1

REFERENCES

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