HIV-1 accessory protein Vpr possesses a cryptic p300-dependent transcription-promoting activity that is blocked by histone deacetylases in CD4+T cells DOI Creative Commons
Catherine A. Lewis, David M. Margolis, Edward P. Browne

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2025, Volume and Issue: unknown

Published: March 27, 2025

Abstract Antiretroviral therapy (ART) has dramatically improved the clinical prognosis for people with HIV and prevents transmission. However, ART does not cure infection because of a persistent, latent reservoir in long-lived cells such as central memory CD4 + T (T CM ) cells. Eliminating or preventing formation will require better understanding HIV-1 latency establishment. We others have recently shown that host cell factors histone deacetylases (HDACs) are critical cellular allow entry into latency. Whether HDACs interact specific viral to regulate establishment, however, is unknown. To examine role individual accessory proteins, we constructed panel reporter strains, each expressing single protein, examined them primary T-cell model. Interestingly, found HDAC inhibitor (HDACi) vorinostat potently enhances effect protein Vpr promoting expression infected cells, suggesting possesses cryptic transcription-promoting activity restricted by HDACs. This was dependent on p300-binding domain inhibited selective p300 acetyltransferase inhibitor. also resulted significant increase proportion phenotype. Furthermore, observed were more resistant Vpr-induced apoptosis/cell death than other subtypes, indicating during selects proviruses Overall, these findings suggest plays an important shaping results, part, from HDAC-mediated restriction Vpr’s activity. Understanding how shape establishment aid development new latency-targeting therapies. Author Summary Although antiretroviral effective at treating HIV, remains elusive. The obstacle presence latently which virus persists despite therapy. Recent work sizable fraction this forms near time initiated, it may be possible prevent some forming. prevention enters latency, including gene silenced. therefore sought interaction between proteins turning off that, whereas turns expression, block Second, leads relative type harbors virus. Our silencing persistence certain types developing approaches targeting

Language: Английский

Genome surveillance by HUSH-mediated silencing of intronless mobile elements DOI Creative Commons
Marta Seczyńska,

Stuart Bloor,

Sergio Martínez Cuesta

et al.

Nature, Journal Year: 2021, Volume and Issue: 601(7893), P. 440 - 445

Published: Nov. 18, 2021

Abstract All life forms defend their genome against DNA invasion. Eukaryotic cells recognize incoming and limit its transcription through repressive chromatin modifications. The human silencing hub (HUSH) complex transcriptionally represses long interspersed element-1 retrotransposons (L1s) retroviruses histone H3 lysine 9 trimethylation (H3K9me3) 1–3 . How HUSH recognizes initiates of these invading genetic elements is unknown. Here we show that able to repress a broad range long, intronless transgenes. Intron insertion into HUSH-repressed transgenes counteracts repression, even in the absence intron splicing. binds transcripts from target locus, prior independent H3K9me3 deposition, essential for both initiation propagation HUSH-mediated H3K9me3. Genomic data reveal how subset endogenous genes generated retrotransposition cellular mRNAs. Thus cDNA—the hallmark reverse transcription—provides versatile way distinguish retroelements host enables protect ‘non-self’ DNA, despite there being no previous exposure element. Our findings existence transcription-dependent genome-surveillance system explain it provides immediate protection newly acquired while avoiding inappropriate repression genes.

Language: Английский

Citations

109
Targeted Protein Degradation by Electrophilic PROTACs that Stereoselectively and Site-Specifically Engage DCAF1 DOI
Yongfeng Tao, David Remillard, Ekaterina V. Vinogradova

et al.

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(40), P. 18688 - 18699

Published: Sept. 28, 2022

Targeted protein degradation induced by heterobifunctional compounds and molecular glues presents an exciting avenue for chemical probe drug discovery. To date, small-molecule ligands have been discovered only a limited number of E3 ligases, which is important limiting factor realizing the full potential targeted degradation. We report herein discovery proteomics azetidine acrylamides that stereoselectively site-specifically react with cysteine (C1113) in ligase substrate receptor DCAF1. demonstrate acrylamide DCAF1 can be developed into electrophilic proteolysis-targeting chimeras (PROTACs) mediated human cells. show this process stereoselective does not occur cells expressing C1113A mutant Mechanistic studies indicate low fractional engagement required to support PROTACs. These findings, taken together, how proteomic analysis stereochemically defined compound sets uncover ligandable sites on ligases

Language: Английский

Citations

83
Transposon–host arms race: a saga of genome evolution DOI
Yuka W. Iwasaki, Keisuke Shoji,

Shinichi Nakagwa

et al.

Trends in Genetics, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 1, 2025

Language: Английский

Citations

2
An E3 ligase guide to the galaxy of small-molecule-induced protein degradation DOI Creative Commons
Predrag Jevtić,

Diane L. Haakonsen,

Michael Rapé

et al.

Cell chemical biology, Journal Year: 2021, Volume and Issue: 28(7), P. 1000 - 1013

Published: April 22, 2021

Language: Английский

Citations

100
TASOR is a pseudo-PARP that directs HUSH complex assembly and epigenetic transposon control DOI Creative Commons
Christopher H. Douse, Iva A. Tchasovnikarova, Richard T. Timms

et al.

Nature Communications, Journal Year: 2020, Volume and Issue: 11(1)

Published: Oct. 2, 2020

Abstract The HUSH complex represses retroviruses, transposons and genes to maintain the integrity of vertebrate genomes. regulates deposition epigenetic mark H3K9me3, but how its three core subunits — TASOR, MPP8 Periphilin contribute assembly targeting remains unknown. Here, we define biochemical basis find that modular architecture resembles yeast RNA-induced transcriptional silencing complex. central subunit, associates with RNA processing components. TASOR is required for H3K9me3 over LINE-1 repeats repetitive exons in transcribed genes. In context previous studies, this suggests an intermediate important activity. We dissect domains necessary transgene repression. Structure-function analyses reveal bears a catalytically-inactive PARP domain targeted deposition. conclude multifunctional pseudo-PARP directs regulation genomic targets.

Language: Английский

Citations

74
The SMC5/6 complex compacts and silences unintegrated HIV-1 DNA and is antagonized by Vpr DOI Creative Commons
Liane Dupont,

Stuart Bloor,

James C. Williamson

et al.

Cell Host & Microbe, Journal Year: 2021, Volume and Issue: 29(5), P. 792 - 805.e6

Published: April 2, 2021

Silencing of nuclear DNA is an essential feature innate immune responses to invading pathogens. Early in infection, unintegrated lentiviral cDNA accumulates the nucleus yet remains poorly expressed. In HIV-1-like lentiviruses, Vpr accessory protein enhances viral expression, suggesting antagonizes cellular restriction. We previously showed how remodels host proteome, identifying multiple targets. now screen these using a targeted CRISPR-Cas9 library and identify SMC5-SMC6 complex localization factor 2 (SLF2) as target responsible for silencing HIV-1. SLF2 recruits SMC5/6 depletion SLF2, or complex, increases expression. ATAC-seq demonstrates that Vpr-mediated chromatin accessibility virus, compacts silence gene This work implicates immunosurveillance extrachromosomal defines its targeting by evolutionarily conserved antagonism.

Language: Английский

Citations

71
TASOR epigenetic repressor cooperates with a CNOT1 RNA degradation pathway to repress HIV DOI Creative Commons
Roy Matkovic, Marina Morel, Sophie Lanciano

et al.

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: Jan. 10, 2022

Abstract The Human Silencing Hub (HUSH) complex constituted of TASOR, MPP8 and Periphilin recruits the histone methyl-transferase SETDB1 to spread H3K9me3 repressive marks across genes transgenes in an integration site-dependent manner. deposition these leads heterochromatin formation inhibits gene expression, but underlying mechanism is not fully understood. Here, we show that TASOR silencing or HIV-2 Vpx which induces degradation, increases accumulation transcripts derived from HIV-1 LTR promoter at a post-transcriptional level. Furthermore, using yeast 2-hybrid screen, identify new partners involved RNA metabolism including deadenylase CCR4-NOT scaffold CNOT1. CNOT1 synergistically repress HIV expression its LTR. Similar RNA-induced transcriptional found fission yeast, interacts with exosome Polymerase II, predominantly under elongating state. Finally, facilitates association degradation proteins polymerase II detected centers. Altogether, propose HUSH operates levels proviral expression.

Language: Английский

Citations

40
The sound of silence: mechanisms and implications of HUSH complex function DOI Creative Commons
Marta Seczyńska, Paul J. Lehner

Trends in Genetics, Journal Year: 2023, Volume and Issue: 39(4), P. 251 - 267

Published: Feb. 6, 2023

The vertebrate genome is under constant threat of invasion by genetic parasites. Whether the host can immediately recognize and respond to invading elements has been unclear. discovery human silencing hub (HUSH) complex, finding that it provides immediate protection from products reverse transcription, have important implications for mammalian evolution. In this review, we summarize recent insights into HUSH function describe how cellular introns provide a novel means self–nonself discrimination, allowing transcriptionally repress broad range intronless elements. We discuss contributes evolution, highlight studies reporting critical role in development implicating control immune signaling cancer progression.

Language: Английский

Citations

39
Keep quiet: the HUSH complex in transcriptional silencing and disease DOI
Iris Müller, Kristian Helin

Nature Structural & Molecular Biology, Journal Year: 2024, Volume and Issue: 31(1), P. 11 - 22

Published: Jan. 1, 2024

Language: Английский

Citations

11
HIV-1 Vpr induces cell cycle arrest and enhances viral gene expression by depleting CCDC137 DOI Creative Commons

Fengwen Zhang,

Paul D. Bieniasz

eLife, Journal Year: 2020, Volume and Issue: 9

Published: June 15, 2020

The HIV-1 Vpr accessory protein induces ubiquitin/proteasome-dependent degradation of many cellular proteins by recruiting them to a cullin4A-DDB1-DCAF1 complex. In so doing, enhances gene expression and (G2/M) cell cycle arrest. However, the identities target through which these biological effects are exerted unknown. We show that chromosome periphery protein, CCDC137/cPERP-B, is targeted for depletion Vpr, in dependent manner. CCDC137 caused G2/M cellcycle arrest, while Vpr-resistant mutants conferred resistance Vpr-induced also recapitulated ability enhance expression, particularly macrophages. Our findings indicate promotes cell-cycle arrest CCDC137.

Language: Английский

Citations

52