(J) The relative binding affinity of HA-tagged full- length and truncated TMEM33 with endogenous SCAP and RNF5. The band intensity of SCAP and RNF5 in Appendix Fig S2E were quantified and normalized to the HA control. TMEM33 protein encompasses three transmembrane (TM) helices in N-terminus and a C-terminal cytosolic domain with a total of 247 aa. 