Involved in regulation of membrane traffic between the Golgi and the endoplasmic reticulum; the function is proposed to depend on its association in the NRZ complex which is believed to play a role in SNARE assembly at the ER. May play a role in cell cycle checkpoint control. Essential for telomere length control (By similarity). Component of the NRZ complex composed of NBAS, ZW10 and RINT1/TIP20L; NRZ associates with SNAREs STX18, USE1L, BNIP1/SEC20L and SEC22B (the assembly has been described as syntaxin 18 complex). Interacts directly with BNIP1/SEC20L and ZW10. Interacts with RAD50 during late S and G2/M phases. Interacts with RBL2, preferentially with the active, hypophosphorylated form (By similarity). Belongs to the RINT1 family.