Fig. 6: SEL1LS658P attenuates its interaction with HRD1.
From: SEL1L-HRD1 interaction is required to form a functional HRD1 ERAD complex
a Schematic diagram of human SEL1L with domains and the location of the variant indicated. SP, signal peptide; FNII, fibronectin type II domain; SLR-N/M/C, Sel1-like repeats at N-, Middle- and C-terminal; TM, transmembrane. b Amino acid sequence alignment of SEL1L showing the conservation of SEL1L S658 residue across species (highlighted in green). c Structural prediction of human SEL1L/OS9/HRD1/DERLIN ERAD complex using AlphaFold2 with SEL1L S658 shown in magenta atoms. The arrow indicates the amphipathic helix of SEL1L that interacts with HRD1. d Side view of a space-filling model of the HRD1-SEL1L interface containing TM1-2 of HRD1 and the amphipathic helix of SEL1L. e Immunoprecipitation of FLAG-agarose in SEL1L−/− HEK293T cells expressing indicated SEL1L-FLAG variants to examine their interaction with HRD1, OS9, and ERLEC1, with quantitation shown below (HRD1: n = 9 each genotype; OS9: n = 8 each genotype; ERLEC1: n = 6 each genotype; “n” indicates independent samples). Values, mean ± SEM. n.s. not significant; ****p < 0.0001 by two-tailed Student’s t test. f Immunoprecipitation of FLAG-agarose in SEL1L−/− HEK293T cells expressing indicated SEL1L-FLAG variants to examine their interaction with HRD1 and OS9 (two independent repeats). g Side view of the HRD1-SEL1L interface. SEL1L S658 and S663 residues are indicated in magenta and orange, respectively. h Immunoprecipitation of SEL1L in the livers from 5-week-old WT and KI mice to examine the interaction between endogenous SEL1L and HRD1, with quantitation of HRD1 shown below the blots as mean values (two independent repeats).
