REL RCSB RCSB RCSB 2013-09-27 2013-10-23 2014-04-23 2014-05-14 Lin J Okada K Raytchev M Smith MC Nicastro D dynein movement, flagellar motility, axoneme Lin J Okada K Raytchev M Smith MC Nicastro D Nat. Cell Biol. 16 479 485 2014 24727830 doi:10.1038/ncb2939 3j68 FULLOVERLAP Cryo-electron tomography and subtomographic average (2800 axonemal repeats) of active sea urchin sperm flagella reveal two distinct pre-powerstroke conformations: pre-I (detached) and pre-II (microtubule-bound). Cryo-electron tomography and subtomographic average (2800 axonemal repeats) of active sea urchin sperm flagella reveal two distinct pre-powerstroke conformations: pre-I (detached) and pre-II (microtubule-bound). 1 dynein

Sperm were frozen while actively beating.

false Strongylocentrotus purpuratus sea urchin sperm flagella subtomogramAveraging cell 8.0

360 mM NaCl, 50 mM MgCl2, 10 mM CaCl2, 10 mM KCl, 30 mM HEPES, pH 8.0

Quantifoil holey carbon grids Cu 200 mesh R2/2

ETHANE 100 HOMEMADE PLUNGER Blot for 1.5-2.5 seconds before plunging FEI TECNAI F30 FLOOD BEAM BRIGHT FIELD FIELD EMISSION GUN 300 6.0 8.0 13500.0 GATAN LIQUID NITROGEN 80 GATAN postcolumn filter GIF 0.0 20.0 2012-04-07 GENERIC GATAN (2k x 2k) 100 Liquid nitrogen cooled -65 65 OTHER 30.0 FSC 0.5 CUT-OFF IMOD, PEET

Final maps were calculated by averaging 2800 particles from 41 tomograms. Axonemal repeats (96 nm long) from 41 tomograms (reconstructed using fiducial alignment and weighted backprojection, IMOD software, Kremer et al. 1996) were aligned and averaged using the PEET software (bio3d.colorado.edu, Nicastro et al. 2006). To obtain structures with consistent conformations, classification of the different conformational states of dynein was performed using a clustering approach implemented in PEET (Heumann et al. 2011).

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