Histone H3K56 Acetylation Is Required for Quelling-induced Small RNA Production through Its Role in Homologous Recombination

Zhenyu Zhang,Qiuying Yang,Guangyan Sun,She Chen,Qun He,Shaojie Li,Yi Liu

doi:10.1074/jbc.m113.528521

Abstract

Quelling and DNA damage-induced small RNA (qiRNA) production are RNA interference (RNAi)-related phenomenon from repetitive genomic loci in Neurospora. We have recently proposed that homologous recombination from repetitive DNA loci allows the RNAi pathway to recognize repetitive DNA to produce small RNA. However, the mechanistic detail of this pathway remains largely unclear. By systematically screening the Neurospora knock-out library, we identified RTT109 as a novel component required for small RNA production. RTT109 is a histone acetyltransferase for histone H3 lysine 56 (H3K56) and H3K56 acetylation is essential for the small RNA biogenesis pathway. Furthermore, we showed that RTT109 is required for homologous recombination and H3K56Ac is enriched around double strand break, which overlaps with RAD51 binding. Taken together, our results suggest that H3K56 acetylation is required for small RNA production through its role in homologous recombination.

Highlights

Quelling and DNA damage induce small RNA from repetitive DNA regions
We recently showed that homologous recombination (HR) pathway is required for quelling and Quelling and DNA damage-induced small RNA (qiRNA) production
A Genetic Screen Identified RTT109 to Be Essential for the DNA Damage-induced qiRNA Production and Quelling—We sought to characterize the mechanism of the DNA damageinduced qiRNA production by carrying a systematic genetic screen using the Neurospora knock-out library [18]

Summary

Introduction

Quelling and DNA damage induce small RNA from repetitive DNA regions. Results: Genetic Screen identified RTT109 as a critical component of the siRNA production pathway in Neurospora. Quelling and DNA damage-induced small RNA (qiRNA) production are RNA interference (RNAi)-related phenomenon from repetitive genomic loci in Neurospora. By systematically screening the Neurospora knock-out mutants, we identify RTT109, a histone acetyltransferase for histone H3 on lysine 56, as a new component in the qiRNA production and quelling pathway.

Results

Conclusion