Extended Data Fig. 6: Conformational properties of the IST2 transmembrane domain.
From: Structural basis for lipid transport at membrane contact sites by the IST2–OSH6 complex
a, Cryo-EM densities of IST2716 constructs in nanodiscs showing ‘narrow’ (left) and ‘wide’ (right) particle reconstructions. A view of the narrow reconstruction along the dimer (bottom) at larger contour illustrates presumable density of the scaffolding protein. Membrane deformations are indicated (#, *). b, View towards the subunit cavity of IST2 structures obtained from the ‘narrow’ (top) and ‘wide’ (bottom) nanodisc reconstructions. Left, cryo-EM density superimposed on the refined structure, right, superposition with the corresponding structure in detergent. Proteins are shown as ribbons. c, Superposition of subunits of the ‘open’ conformations of IST2 and nhTMEM16 (PDBID 6QM9). d, Diameter of the open subunit cavity in IST2 and nhTMEM16 measured by Hole74. Inset (right) indicates the start and end of mapped positions in the cavities of both proteins. e, Superposition of the densities of the membrane inserted part of the IST2/OSH6 complex and the IST2716 subunit (low pass filtered to the same resolution) illustrates a different conformation of α4 and α6. A blowup of the marked region is shown right. f, View towards the subunit cavity of the collapsed conformation of IST2 observed in the IST2/OSH6 complex. Left, cryo-EM density superimposed on the refined structure, right, superposition with IST2716 in detergent. Proteins are shown as ribbons.
