PMC:6120343 / 5816-7323 JSONTXT

{"project":"2_test","denotations":[{"id":"29899447-23584531-75119393","span":{"begin":1363,"end":1365},"obj":"23584531"},{"id":"29899447-23584531-75119393","span":{"begin":1363,"end":1365},"obj":"23584531"},{"id":"29899447-21927000-75119394","span":{"begin":1366,"end":1368},"obj":"21927000"},{"id":"29899447-21927000-75119394","span":{"begin":1366,"end":1368},"obj":"21927000"},{"id":"29899447-21927001-75119395","span":{"begin":1369,"end":1371},"obj":"21927001"},{"id":"29899447-21927001-75119395","span":{"begin":1369,"end":1371},"obj":"21927001"},{"id":"29899447-20428112-75119396","span":{"begin":1372,"end":1374},"obj":"20428112"},{"id":"29899447-20428112-75119396","span":{"begin":1372,"end":1374},"obj":"20428112"},{"id":"29899447-20538602-75119396","span":{"begin":1372,"end":1374},"obj":"20538602"},{"id":"29899447-20538602-75119396","span":{"begin":1372,"end":1374},"obj":"20538602"},{"id":"29899447-26302298-75119396","span":{"begin":1372,"end":1374},"obj":"26302298"},{"id":"29899447-26302298-75119396","span":{"begin":1372,"end":1374},"obj":"26302298"}],"text":"Structure of the DRP1-MID49 cofilament\nIncubating equimolar ratios of DRP1 with soluble MID49126-454, MID51132-463, or both proteins together, in the presence of Mg2+, GTP or GTP analogs GMPPCP/GTPγS, but not other nucleotides, resulted in cofilament assembly (Extended Data Fig. 1). We focused on the filaments formed with MID49126-454 in the presence of GMPPCP and determined their structure from cryoEM images to an average resolution of 4.2Å (from ~3.5Å to ~8Å, Extended Data Figs. 2–6 and Supplementary Table 1). 3D reconstruction revealed a polymer comprised of three equivalent faces that meet through defined vertices to form a triangular assembly (Extended Data Figs 2–3). A combination of helical reconstruction, segmentation, and single-particle alignment and averaging resolved the elongated DRP1 subunits bound stoichiometrically to MID49126-454, but without assignable density for the majority of the variable domain (Fig. 1b, Extended Data Fig. 2–6). Surprisingly, each chain of DRP1 bound MID49 via four different surfaces, and each MID49 in turn bound four DRP1 molecules to yield a vast interaction network (Figs. 1b-c, Extended Data Figs. 2, 3a-c). MID49 binding to four DRP1 molecules stabilized a linear arrangement of inter-DRP1 interfaces reminiscent of those observed for other dynamin-family proteins (Fig. 1b, Extended Data Figs. 2c, 3d)25,32,33,38–40. We refer to the four distinct surfaces of DRP1 that contribute to MID49/51 binding as receptor interfaces 1 through 4 (Fig. 1c)."}