ERLIN2 encodes an endoplasmic reticulum (ER) membrane protein that forms oligomeric complexes crucial for cellular quality control and metabolic regulation. The protein assembles into cage-like structures containing 13 pairs of ERLIN1-ERLIN2 heterodimers or 26 ERLIN2 homodimers, serving as platforms for protein degradation pathways 1. ERLIN2 participates in endoplasmic reticulum-associated degradation (ERAD) and regulates cholesterol homeostasis through the SREBP signaling pathway 2. The protein interacts with various partners including SCAP-SREBF complexes and can stabilize proteins like SREBP1 by inhibiting ubiquitination 3. ERLIN2 mutations are associated with hereditary spastic paraplegia (HSP), specifically types 18A (autosomal dominant) and 18B (autosomal recessive) 4. Disease-causing variants can activate ER stress responses and alter axonal development, with a novel V71A variant demonstrating increased XBP-1S mRNA levels and modified ER morphology 5. The protein also plays roles in cancer biology, where it can influence tumor cell proliferation and metastasis through stabilization of cell cycle regulators like Cyclin B1 6.