Xiaoyan Wang, Yuan Wang, Yongchao Dou, Lu Chen, Junli Wang, Ning Jiang, Chunce Guo, Qingqing Yao, Chizao Wang, Lin Liu, Bin Yu, Binglian Zheng, Julia A Chekanova, Jinbiao Ma, Guodong Ren
The 3' end methylation catalyzed by HUA Enhancer 1 (HEN1) is a crucial step of small RNA stabilization in plants, yet how unmethylated small RNAs undergo degradation remains largely unknown. Using a reverse genetic approach, we here show that Atrimmer 2 (ATRM2), a DEDDy-type 3' to 5' exoribonuclease, acts in the degradation of unmethylated miRNAs and miRNA*s in Arabidopsis Loss-of-function mutations in ATRM2 partially suppress the morphological defects caused by HEN1 malfunction, with restored levels of a subset of miRNAs and receded expression of corresponding miRNA targets...
July 10, 2018: Proceedings of the National Academy of Sciences of the United States of America