Scaffolding subunit of the trimeric nuclear exosome targeting (NEXT) complex that is involved in the surveillance and turnover of aberrant transcripts and non-coding RNAs. NEXT functions as an RNA exosome cofactor that directs a subset of non-coding short-lived RNAs for exosomal degradation. May be involved in pre-mRNA splicing. It is required for 3'-end maturation of telomerase RNA component (TERC), TERC 3'-end targeting to the nuclear RNA exosome, and for telomerase function. Component of a nuclear TRAMP-like complex, an ATP-dependent exosome regulatory complex consisting of a helicase (MTREX), an oligadenylate polymerase (TENT4B or TENT4A), and a substrate specific RNA-binding factor (ZCCHC7 or ZCCHC8). Several TRAMP-like complexes exist with specific compositions and are associated with nuclear, or nucleolar RNA exosomes. Identified in the spliceosome C complex. Component of the nuclear exosome targeting (NEXT) complex composed of MTREX, ZCCHC8, and RBM7 that directs a subset of non-coding short-lived RNAs for exosomal degradation. Interacts with proteins involved in RNA processing and degradation such as MTREX and RBM7; interaction with MTREX enhances MTREX RNA helicase activity and bridges between RBM7 and MTREX. Interacts with TERC, the telomerase RNA component. Excluded from nucleolus. The C-terminal part (659-707) contributes to MTREX RNA helicase activity, in part, by enhancing its RNA-dependent ATPase activity. Phosphorylation at Thr-490 by GSK3 is triggered in cells entering mitosis. Belongs to the ZCCHC8 family.