A Synthetic Transcriptional Activator of Genes Associated with the Retina in Human Dermal Fibroblasts.

Small molecules capable of modulating epigenetic signatures can activate the transcription of tissue-restricted genes in a totally unrelated cell type and have potential use in epigenetic therapy. To provide an example for an initial approach, we report here on one synthetic small-molecule compound-termed "SAHA-PIP X"-from our library of conjugates. This compound triggered histone acetylation accompanied by the transcription of retinal-tissue-related genes in human dermal fibroblasts (HDFs)

SPRTN protease-cleaved MRE11 decreases DNA repair and radiosensitises cancer cells

Funding Information: This work was funded by CRUK Programme Grant C5255/A23755. Acknowledgements Mass spectrometry analysis was performed in the MS laboratory at the Target discovery institute—NDM (Oxford) led by Benedikt M. Kessler. We thank Drs. Eva McGrowder and Blaz Groselj for processing of primary bladder tumour samples to produce cell-free extracts. Data availability The LC-MS/MS proteomics data have been deposited to the ProteomeXchange Consortium via the PRIDE48 partner repository with the dataset identifier PXD017964 and 10.6019/PXD017964.Peer reviewedPublisher PD

ケミカルバイオロジー的アプローチによる真核細胞の遺伝子発現制御法の検討

京都大学0048新制・課程博士博士(理学)甲第19261号理博第4116号新制||理||1592(附属図書館)32263京都大学大学院理学研究科化学専攻(主査)教授 杉山 弘, 教授 三木 邦夫, 教授 藤井 紀子学位規則第4条第1項該当Doctor of ScienceKyoto UniversityDGA

RNA-DNA Triplex Formation by Long Noncoding RNAs

Long noncoding RNAs (lncRNAs) play a pivotal role in the regulation of biological processes through various mechanisms that are not fully understood. Proposed mechanisms include regulation based on RNA-protein interactions, as well as RNA-RNA interactions and RNA-DNA interactions. Here, we focus on one possible mechanism that lncRNA might be using to impact biological function, the RNA-DNA triplex formation. We summarize currently available examples of lncRNA triplex formation and discuss the details surrounding orientation of triplex formation as one of the key properties guiding this process. We propose that symmetrical triplex-forming motifs, especially those in cis-acting lncRNAs, favor triplex formation. We also consider the effects of lncRNA structures, protein or ligand binding, and chromatin structures on the lncRNAs triplex formation

Alteration of epigenetic program to recover memory and alleviate neurodegeneration: prospects of multi-target molecules

Accepted 12 Apr 2014.Epigenetic chromatin remodeling and signalling pathways play an integral role in transcription dependent neurodegeneration and long-term potentiation (LTP), a cellular model associated with learning and memory. Pathological epigenetic modifications associated with neurological disorders are inherently flexible and can be reversed through pharmacological intervention. Small molecules are the favored drugs for clinicians, and in neurological disorders associated with complex cellular mechanisms, epigenetic and/or signalling pathway enzymes inhibiting small molecules have shown clinical prospects. Recently, small molecules with two or more functionalities, such as sequence-specific recognition and signalling pathways and/or enzyme modulation, have shown capabilities as efficient transcriptional activators. Here, we give a balanced overview of the key factors associated with memory recovery and neurodegeneration, available chemical tools for modulation and the demand to develop next-generation small molecules with multi-functional activities to treat such intricate, multi-gene associated neurological disorders

Targeted Suppression of EVI1 Oncogene Expression by Sequence-Specific Pyrrole-Imidazole Polyamide.

Human ectopic viral integration site 1 (EVI1) is an oncogenic transcription factor known to play a critical role in many aggressive forms of cancer. Its selective modulation is thought to alter the cancer-specific gene regulatory networks. Pyrrole-imidazole polyamides (PIPs) are a class of small DNA binders that can be designed to target any destined DNA sequence. Herein, we report a sequence-specific pyrrole-imidazole polyamide, PIP1, which can target specific base pairs of the REL/ELK1 binding site in the EVI1 minimal promoter. The designed PIP1 significantly inhibited EVI1 in MDA-MB-231 cells. Whole-transcriptome analysis confirmed that PIP1 affected a fraction of EVI1-mediated gene regulation. In vitro assays suggested that this polyamide can also effectively inhibit breast cancer cell migration. Taken together, these results suggest that EVI1-targeted PIP1 is an effective transcriptional regulator in cancer cells

Genome-Wide Assessment of the Binding Effects of Artificial Transcriptional Activators by High-Throughput Sequencing

One of the major goals in DNA-based personalized medicine is the development of sequence-specific small molecules to target the genome. SAHA-PIPs belong to such class of small molecule. In the context of the complex eukaryotic genome, the differential biological effects of SAHA-PIPs are unclear. This question can be addressed by identifying the binding regions across the genome; however, it is a challenge to enrich small-molecule-bound DNA without chemical crosslinking. Here, we developed a method that employs high-throughput sequencing to map the binding area of small molecules throughout the chromatinized human genome. Analysis of the sequenced data confirmed the presence of specific binding sites for SAHA-PIPs from the enriched sequence reads. Mapping the binding sites and enriched regions on the human genome clarifies the reason for the distinct biological effects of SAHA-PIP. This approach will be useful for identifying the function of other small molecules on a large scale

Distinct DNA-based epigenetic switches trigger transcriptional activation of silent genes in human dermal fibroblasts.

人工スイッチを使った遺伝子コントロールに成功 -治療に役立つ可能性も- 京都大学プレスリリース. 2014-01-24.The influential role of the epigenome in orchestrating genome-wide transcriptional activation instigates the demand for the artificial genetic switches with distinct DNA sequence recognition. Recently, we developed a novel class of epigenetically active small molecules called SAHA-PIPs by conjugating selective DNA binding pyrrole-imidazole polyamides (PIPs) with the histone deacetylase inhibitor SAHA. Screening studies revealed that certain SAHA-PIPs trigger targeted transcriptional activation of pluripotency and germ cell genes in mouse and human fibroblasts, respectively. Through microarray studies and functional analysis, here we demonstrate for the first time the remarkable ability of thirty-two different SAHA-PIPs to trigger the transcriptional activation of exclusive clusters of genes and noncoding RNAs. QRT-PCR validated the microarray data, and some SAHA-PIPs activated therapeutically significant genes like KSR2. Based on the aforementioned results, we propose the potential use of SAHA-PIPs as reagents capable of targeted transcriptional activation

Deciphering the genomic targets of alkylating polyamide conjugates using high-throughput sequencing

Chemically engineered small molecules targeting specific genomic sequences play an important role in drug development research. Pyrrole-imidazole polyamides (PIPs) are a group of molecules that can bind to the DNA minor-groove and can be engineered to target specific sequences. Their biological effects rely primarily on their selective DNA binding. However, the binding mechanism of PIPs at the chromatinized genome level is poorly understood. Herein, we report a method using high-throughput sequencing to identify the DNA-alkylating sites of PIP-indole-seco-CBI conjugates. High-throughput sequencing analysis of conjugate 2 showed highly similar DNA-alkylating sites on synthetic oligos (histone-free DNA) and on human genomes (chromatinized DNA context). To our knowledge, this is the first report identifying alkylation sites across genomic DNA by alkylating PIP conjugates using high-throughput sequencing