Transcriptional regulator which binds to the E box motif 5'-CACGTG-3', when in a heterodimeric complex with mxl-1 (PubMed:9764821). Involved in the control of lifespan in response to dietary restriction, the decline in protein homeostasis associated with normal aging, germline signaling and may overlap with the insulin-like signaling pathway (PubMed:24699255, PubMed:27001890). Plays a role in autophagy (PubMed:27001890). Involved in promoting infection by the microsporidian pathogen N.parisii, possibly together with transcription factors pha-4 and zip-10 (PubMed:27402359). Heterodimer with mxl-1 in presence and absence of DNA. Expressed in intestinal cells in adults. Expressed weakly in larval stage L1 and strongly throughout the remainder of larval development (PubMed:9764821). Expressed in larval posterior intestinal cells and neurons (PubMed:9764821, PubMed:27402359). RNAi-mediated knockdown increases lifespan, which is abolished on an mxl-2 or mml-1 mutant background, or by simultaneous RNAi-mediated knockdown of daf-16 or pha-4 (PubMed:24699255). RNAi-mediated knockdown causes delayed onset of polyglutamine-mediated paralysis (PubMed:24699255). RNAi-mediated knockdown reduces spore levels of the microsporidian pathogen N.parisii during infection, further reduced on an mxl-2 mutant background (PubMed:27402359).