Required for the hydrolytic deamination of adenosine to inosine in double-stranded RNA (dsRNA) referred to as A-to-I RNA editing (PubMed:12426375). Does not have deaminase activity but binds to dsRNA and regulates A-to-I RNA editing, possibly by modulating the accessibility of the double-stranded RNA-specific adenosine deaminase adr-2 for target adenosines (PubMed:24508457, PubMed:25373143). Regulates editing efficiency of specific adenosines in 3' untranslated regions of target mRNAs (PubMed:24508457). Represses editing efficiency of the Y75B8A.8 3' UTR in neurons (PubMed:26917557). Required for correct expression and A-to-I editing of clec-41 (PubMed:28925356). Required for normal chemotaxis (PubMed:12426375, PubMed:14657490). Also required for normal vulva development (PubMed:12426375). Plays a role in determining lifespan (PubMed:20011587, PubMed:25373143). Not required for RNA interference (PubMed:12419225). Likely to play a role in determining whether a dsRNA enters the RNAi pathway (PubMed:14657490). Interacts with double-stranded RNA-specific adenosine deaminase adr-2. Detected both in the nuclear fraction and in the ribosome-containing pellet of the cytoplasm. Expression begins early in embryogenesis where it is detected in late gastrula and comma stage embryos. By the comma stage, expression is highest in developing neuronal tissue in the head, tail and ventral side. Neuronal expression continues through embryogenesis and, by the L1 larval stage, is the prominent pattern. Expressed in most, if not all, cells of the nervous system at all larval stages and in adult animals. Also expressed in the developing vulva but not expressed in the adult vulva. Highest expression observed in the embryo. Levels decrease dramatically after embryogenesis, remain relatively constant during larval stages and increase again at the onset of adulthood. Can prevent somatic transgenes from inducing gene silencing via the RNA interference pathway. This may occur due to A-to-I editing of transgene-derived dsRNA, preventing transgene RNAi.