SMA1, a homolog of the splicing factor Prp28, has a multifaceted role in miRNA biogenesis in Arabidopsis

Authors

Shengjun Li, University of Nebraska-LincolnFollow
Ran Xu, Chinese Academy of Sciences
Aixia Li, Chinese Academy of Sciences
Kan Liu, University of Nebraska-LincolnFollow
Liqing Gu, Chinese Academy of Sciences
Mu Li, University of Nebraska-LincolnFollow
Hairui Zhang, Shanxi Normal University
Yueying Zhang, Chinese Academy of Sciences
Shangshang Zhuang, Chinese Academy of Sciences
Quanhui Wang, Chinese Academy of Sciences
Gang Gao, Shanxi Normal University
Na Li, Chinese Academy of Sciences
Chi Zhang, University of Nebraska-LincolnFollow
Yunhai Li, Chinese Academy of SciencesFollow
Bin Yu, University of Nebraska - LincolnFollow

Document Type

Article

Date of this Version

2018

Citation

Nucleic Acids Research, 2018, Vol. 46, No. 17

Comments

Copyright The Author(s) 2018.

Open access

doi: 10.1093/nar/gky591

Abstract

MicroRNAs (miRNAs) are a class of small non-coding RNAs that repress gene expression. In plants, the RNase III enzyme Dicer-like (DCL1) processes primary miRNAs (pri-miRNAs) into miRNAs. Here, we show that SMALL1 (SMA1), a homolog of the DEADbox pre-mRNA splicing factor Prp28, plays essential roles in miRNA biogenesis in Arabidopsis. A hypomorphic sma1-1 mutation causes growth defects and reduces miRNA accumulation correlated with increased target transcript levels. SMA1 interacts with the DCL1 complex and positively influences primiRNA processing. Moreover, SMA1 binds the promoter region of genes encoding pri-miRNAs (MIRs) and is required for MIR transcription. Furthermore, SMA1 also enhances the abundance of the DCL1 protein levels through promoting the splicing of the DCL1 pre-mRNAs. Collectively, our data provide new insights into the function of SMA1/Prp28 in regulating miRNA abundance in plants.