Acute targeting of general transcription factor IIB restricts cardiac hypertrophy via selective inhibition of gene transcription.
Acute targeting of general transcription factor IIB restricts cardiac hypertrophy via selective inhibition of gene transcription.
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DOI：
10.1161/circheartfailure.114.001660
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发表时间：
2015-01
期刊：
影响因子：
--
通讯作者：
Abdellatif M
中科院分区：
文献类型：
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作者：
Sayed D;Yang Z;He M;Pfleger JM;Abdellatif M
我们以前报道，专门和管家基因的差异调节，通过从头招聘和暂停释放RNA聚合酶II（pol II），分别在心脏肥大。然而，这一发现的重要性仍有待研究。因此，本研究的目的是确定差异调节这些基因组的机制，并利用它们进行治疗靶向。在这里，我们发现，一般转录因子IIB（TFIIB）和细胞周期蛋白依赖性激酶9在肥大过程中上调，都由miR-1靶向，并在调节这两组基因中发挥优先作用。染色质免疫沉淀测序显示，TFIIB是组成性结合到所有暂停，管家，启动子，而从头招募TFIIB和pol II是所需的肥大过程中诱导的专门的基因。我们利用这种二分法，急性抑制诱导后一组，其中包括心肌病，免疫反应，和细胞外基质基因，使用锁核酸（LNA）修饰的反义TFIIB寡核苷酸治疗。这导致抑制了所有特化基因，而保留了管家基因，从而减弱了病理性肥大。这些数据首次揭示了不同的一般转录因子IIB的动态，在心脏肥大过程中调节专门与管家基因。因此，通过急性靶向TFIIB，我们能够选择性地抑制前一组基因并改善压力超负荷肥大。我们还证明了使用LNA修饰的反义寡核苷酸急性和可逆地靶向心脏mRNA用于治疗目的的可行性。
We previously reported that specialized and housekeeping genes are differentially regulated via de novo recruitment and pause-release of RNA polymerase II (pol II), respectively, during cardiac hypertrophy. However, the significance of this finding remains to be examined. Therefore, the purpose of this study was to determine the mechanisms that differentially regulate these gene groups and exploit them for therapeutic targeting. Here we show that general transcription factor IIB (TFIIB) and cyclin-dependent kinase 9 are upregulated during hypertrophy, both targeted by miR-1, and play preferential roles in regulating those two groups of genes. Chromatin immunoprecipitation-sequencing reveals that TFIIB is constitutively bound to all paused, housekeeping, promoters, whereas, de novo recruitment of TFIIB and pol II is required for specialized genes that are induced during hypertrophy. We exploited this dichotomy to acutely inhibit induction of the latter set, which encompasses cardiomyopathy, immune reaction, and extracellular matrix genes, using locked nucleic acid (LNA)-modified antisense TFIIB oligonucleotide treatment. This resulted in suppression of all specialized genes, while sparing the housekeeping ones, and, thus, attenuated pathological hypertrophy. The data for the first time reveal distinct general transcription factor IIB dynamics that regulate specialized vs. housekeeping genes during cardiac hypertrophy. Thus, by acutely targeting TFIIB we were able to selectively inhibit the former set of genes and ameliorate pressure overload hypertrophy. We also demonstrate the feasibility of acutely and reversibly targeting cardiac mRNA for therapeutic purposes using LNA-modified antisense oligonucleotides.