Arginine methylation,catalyzed by the Protein Arginine Methyltransferases(PRMTs),is involved in multiple biological processes.AtPRMT5,an Arabidopsis type Ⅱ enzyme,regulates plant growth and development by modulating pre-mRNA splicing.Nevertheless,the precise mechanism remains largely unknown.Here we reported that AtPRMT5 is essential for the recruitment of Prp19C/NTC and splicing factors specific for the catalytic reactions to the spliceosome.