Journal: bioRxiv
Article Title: Structural dynamics of the active HER4 and HER2/HER4 complexes is finely tuned by different growth factors and glycosylation
doi: 10.1101/2023.10.06.561161
Figure Lengend Snippet: a , Overview of the HER2/HER4 purification strategy. HER2 features a G778D (GD) mutation to mediate Hsp90-independence. VR corresponds to HER2-V956R (receiver) and IQ to HER4-I712Q (activator). The mutant complex was used for all purification and structure determination steps shown in this figure and is referred to as HER2/HER4. b , Coomassie-stained SDS-PAGE gel analysis of the samples from the HER2/HER4 purification after ligand-mediated pulldown (1 st step) and MBP pulldown (2 nd step). c, Representative Size Exclusion Chromatography (SEC) profiles for liganded HER2/HER4 heterocomplexes. d , Representative 2D cryo-EM class averages of liganded HER2/HER4/NRG1β heterocomplexes. Box size is 321 Å. e , Western Blot showing that activation of HER2/HER4 heterodimers requires HER2 to adopt the kinase receiver function (HER2-VR) and HER4 to adopt the kinase activator (HER4-IQ) function in the heterodimer. Constructs were co-transfected into COS7 cells, starved overnight and stimulated with 10 nM ligand for 10 min at 37 °C. The blot is representative of three independent experiments.
Article Snippet: Cells were rinsed in PBS 5 hours post transfection, serum-starved for 16 hours and, if applicable, stimulated with 10 nM NRG1β (PeproTech) or BTC (PeproTech) for 10 minutes at 37° C. Cells were then washed with ice-cold PBS two times and lysed in 300 μl RIPA buffer (50 mM TRIS pH 8, 150 mM NaCl, 1% NP40, 0.5% sodium deoxycholate, 0.1% SDS, 1 mM EDTA, Roche Complete protease inhibitors, DNAse, 1 mM sodium orthovanadate, 1 mM sodium fluoride) on ice for 30 minutes.
Techniques: Purification, Mutagenesis, Staining, SDS Page, Size-exclusion Chromatography, Cryo-EM Sample Prep, Western Blot, Activation Assay, Construct, Transfection