Essential for dosage compensation (PubMed:7588066). Required for the sex-specific association of the dosage compensation complex proteins dpy-27 and dpy-26 with the hermaphrodite X chromosomes (PubMed:7588066, PubMed:8939869). Plays a role in developmental rate and body fat regulation downstream of the TOR complex 2 (PubMed:23884442). Required for the robust transdifferentiation of the Y rectal cell to the PDA motor neuron during larval development (PubMed:25124442). Component of the SET2 complex (also known as the SET1/COMPASS complex), which contains at least set-2, swd-2.1, cfp-1, rbbp-5, wdr-5.1, dpy-30 and ash-2 (PubMed:31602465). Within the complex, interacts with cfp-1 and wdr-5.1 (PubMed:31602465). Interacts with jmjd-3.1 (PubMed:25124442). Expressed both maternally and zygotically in all stages. RNAi-mediated knockdown suppresses the growth delay and elevated body fat index of the TOR complex 2 mutant rict-1 (PubMed:23884442). Results in disruption of the invariant transdifferentiation of the Y rectal cell to the PDA motor neuron (PubMed:25124442). Belongs to the dpy-30 family.