Received March 14, 2007
Accepted June 8, 2007
Mutations in the Type II Protein Arginine Methyltransferase AtPRMT5 Result in Pleiotropic Developmental Defects in Arabidopsis thaliana
Yanxi Pei , Lifang Niu , Falong Lu , Chunyan Liu , Jixian Zhai , Xiangfeng Kong , and Xiaofeng Cao *
College of Life Science and Technology, Shanxi University, Taiyuan, China, 030006; State Key Laboratory of Plant Genomics and Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China 100101; Graduate School, Chinese Academy of Sciences, Beijing, China, 100039
* Corresponding author; email: xfcao{at}genetics.ac.cn.
Human protein arginine methyltransferase 5 (PRMT5) encodes a type II protein arginine methyltransferase and its homologs in animals and yeast are known to regulate RNA processing, signal transduction and gene expression. However, PRMT5 homologs in higher plants have not yet been reported and the biological roles of these proteins in plant development remain elusive. Here, using conventional biochemical approaches, we purified a plant histone arginine methyltransferase from cauliflower that was nearly identical to AtPRMT5, an Arabidopsis homolog of human PRMT5. AtPRMT5 methylated histone H4, H2A and myelin basic protein (MBP) in vitro. Western blot using symmetric di-methyl histone H4 arginine 3 specific antibody and thin layer chromatography (TLC) analysis demonstrated that AtPRMT5 is a type II enzyme. Mutations in AtPRMT5 caused pleiotropic developmental defects, including growth retardation, dark green and curled leaves, and FLC-dependent delayed flowering. Therefore, the type II protein arginine methyltransferase AtPRMT5 is involved in repression of vegetative growth and FLC-dependent flowering time regulation in Arabidopsis.
