Stimulator of protein export for NES-containing proteins (By similarity). Plays a role in the nuclear export of mRNA (PubMed:14729961). Also plays a role in the nuclear export of U1 snRNA, tRNA, and mRNA (By similarity). In ovaries, plays a role in transposable element silencing regulation (PubMed:31219034, PubMed:31368590, PubMed:31384064, PubMed:31570835, PubMed:33856346). Forms a complex with nxf2, Panx and piwi which acts as effector of cotranscriptional transposon silencing (PubMed:31219034, PubMed:31368590, PubMed:31384064, PubMed:31570835). In ovarian follicle cells, enables the nuclear export of flamenco (flam) transcripts and subsequent piRNA biogenesis (PubMed:33856346). Forms a complex with RanGAP, Nup358/RanBP2 and sbr/Nxf1 (PubMed:14729961). In the ovaries, part of a complex composed of at least Panx, nxf2, piwi and Nxt1 (PubMed:31570835, PubMed:31219034, PubMed:31368590, PubMed:31384064). The complex is knowns as Panx-induced cotranscriptional silencing (PICTS) complex, Panx-nxf2-dependent TAP/p15 silencing (Pandas complex), SFiNX (silencing factor interacting nuclear export variant) or piwi-Panx-nxf2-p15 (PPNP) complex (PubMed:31570835, PubMed:31219034, PubMed:31368590, PubMed:31384064). Interacts with nxf2 (via NTF2 domain); the interaction is direct and prevents Nxt1 binding to nucleoporins (PubMed:31368590). Interacts with sbr/nxf1 (PubMed:31570835). Interacts with Nup54 and Nup58 (PubMed:33856346). Associates with the nuclear pore complex. Expressed in female gonads (at protein level). RNAi-mediated knockdown in the germline increases transposon expression.