{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T14:40:43Z","timestamp":1791297643962,"version":"4.1.0"},"reference-count":44,"publisher":"Rockefeller University Press","issue":"5","content-domain":{"domain":["rupress.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2015,12,7]]},"abstract":"<jats:p>Depletion of Drosophila melanogaster Asp, an orthologue of microcephaly protein ASPM, causes spindle pole unfocusing during mitosis. However, it remains unclear how Asp contributes to pole focusing, a process that also requires the kinesin-14 motor Ncd. We show that Asp localizes to the minus ends of spindle microtubule (MT) bundles and focuses them to make the pole independent of Ncd. We identified a critical domain in Asp exhibiting MT cross-linking activity in vitro. Asp was also localized to, and focuses the minus ends of, intraspindle MTs that were nucleated in an augmin-dependent manner and translocated toward the poles by spindle MT flux. Ncd, in contrast, functioned as a global spindle coalescence factor not limited to MT ends. We propose a revised molecular model for spindle pole focusing in which Asp at the minus ends cross-links MTs at the pole and within the spindle. Additionally, this study provides new insight into the dynamics of intraspindle MTs by using Asp as a minus end marker.<\/jats:p>","DOI":"10.1083\/jcb.201507001","type":"journal-article","created":{"date-parts":[[2015,12,8]],"date-time":"2015-12-08T11:07:31Z","timestamp":1449572851000},"page":"999-1009","update-policy":"https:\/\/doi.org\/10.1083\/jcb.crossmarkpolicy","source":"Crossref","is-referenced-by-count":55,"title":["Microcephaly protein Asp focuses the minus ends of spindle microtubules at the pole and within the spindle"],"prefix":"10.1083","volume":"211","author":[{"given":"Ami","family":"Ito","sequence":"first","affiliation":[{"name":"Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gohta","family":"Goshima","sequence":"additional","affiliation":[{"name":"Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"291","published-online":{"date-parts":[[2015,12,7]]},"reference":[{"key":"2023072308032945800_bib1","doi-asserted-by":"publisher","first-page":"e1005261","DOI":"10.1371\/journal.pgen.1005261","article-title":"Dissecting the function and assembly of acentriolar microtubule organizing centers in Drosophila cells in vivo","volume":"11","author":"Baumbach","year":"2015","journal-title":"PLoS Genet."},{"key":"2023072308032945800_bib2","doi-asserted-by":"publisher","first-page":"39","DOI":"10.1007\/978-1-60327-993-2_3","article-title":"RNAi in Drosophila S2 cells as a tool for studying cell cycle progression","volume":"545","author":"Bettencourt-Dias","year":"2009","journal-title":"Methods Mol. 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