Involved in Golgi-to-endoplasmic reticulum (ER) retrograde transport; 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 (PubMed:19369418). Required for normal embryonic development (By similarity). May play a role in the nonsense-mediated decay pathway of mRNAs containing premature stop codons (By similarity).