Component of the ERI/DICER complex which is involved in processing amplified double-stranded RNA (dsRNA) intermediates during small-RNA-mediated gene-silencing or RNA interference (RNAi) (Probable). Involved in cleaving dsRNA in the RNAi pathway (PubMed:11641272, PubMed:20223951). It produces 21 to 23 bp dsRNAs (siRNAs) which target the selective destruction of homologous RNAs (PubMed:11641272, PubMed:20223951). Seems to process the precursor of the small temporal RNA let-7 which is involved in developmental timing (PubMed:11641272). Required for avoidance behavior induced by small RNAs derived from pathogenic bacteria such as P.aeruginosa (PubMed:32908307). Involved in innate immunity through its role in small RNA processing. tDCR-1 acts as a deoxyribonuclease (DNase) initiating DNA fragmentation during apoptosis, upstream of nucleases cps-6, crn-2 and nuc-1. Component of the ERI/DICER complex at least composed of dcr-1, rrf-3 and eri-1 (Probable). Interacts with pir-1 (PubMed:16439208, PubMed:33378643). RNAi-mediated knockdown in a cps-6 mutant background reduces the number of DNA breaks in embryonic cells undergoing apoptosis. The avoidance behavior is transgenerationally inherited, and thus progeny display this same aversion despite never been exposed to this pathogenic bacteria. Belongs to the helicase family. Dicer subfamily.