5W3H:
reference: Structural differences between yeast and mammalian microtubules revealed by cryo-EM., Howes SC, Geyer EA, LaFrance B, Zhang R, Kellogg EH, Westermann S, Rice LM, Nogales E, J Cell Biol. 2017 Sep 4;216(9):2669-2677. doi: 10.1083/jcb.201612195. Epub 2017, Jun 26. PMID: 28652389

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