DCL1 (EC=3.1.26) is a ribonuclease (RNase) III involved in RNA-mediated post-transcriptional gene silencing (PTGS). Functions in the microRNAs (miRNAs) biogenesis pathway by cleaving primary miRNAs (pri-miRNAs) and precursor miRNAs (pre-miRNAs). Synonymes: Protein ABNORMAL SUSPENSOR 1, Protein CARPEL FACTORY, Protein SHORT, INTEGUMENTS 1, Protein SUSPENSOR 1.