{"entity": "journal", "iuid": "ba066550376345d08cdeb91e4d1fd55d", "timestamp": "2026-07-22T17:11:41.819Z", "links": {"self": {"href": "https://publications-affiliated.scilifelab.se/journal/Experimental%20Cell%20Research.json"}, "display": {"href": "https://publications-affiliated.scilifelab.se/journal/Experimental%20Cell%20Research"}}, "title": "Experimental Cell Research", "issn": "0014-4827", "issn-l": "0014-4827", "publications_count": 2, "publications": [{"entity": "publication", "iuid": "89b9bc65a411441ebc979c37d83225c8", "links": {"self": {"href": "https://publications-affiliated.scilifelab.se/publication/89b9bc65a411441ebc979c37d83225c8.json"}, "display": {"href": "https://publications-affiliated.scilifelab.se/publication/89b9bc65a411441ebc979c37d83225c8"}}, "title": "Upregulated Op18/stathmin activity causes chromosomal instability through a mechanism that evades the spindle assembly checkpoint", "authors": [{"family": "Holmfeldt", "given": "Per", "initials": "P"}, {"family": "Sellin", "given": "Mikael E", "initials": "ME"}, {"family": "Gullberg", "given": "Martin", "initials": "M"}], "type": "journal-article", "published": "2010-07-00", "journal": {"volume": "316", "issn": "0014-4827", "issue": "12", "pages": "2017-2026", "title": "Experimental Cell Research", "issn-l": "0014-4827"}, "abstract": "Op18/stathmin (Op18) is a microtubule-destabilizing protein that is phosphorylation-inactivated during mitosis and its normal function is to govern tubulin subunit partitioning during interphase. Human tumors frequently overexpress Op18 and a tumor-associated Q18-->E mutation has been identified that confers hyperactivity, destabilizes spindle microtubules, and causes mitotic aberrancies, polyploidization, and chromosome loss in K562 leukemia cells. Here we determined whether wild-type and mutant Op18 have the potential to cause chromosomal instability by some means other than interference with spindle assembly, and thereby bypassing the spindle assembly checkpoint. Our approach was based on Op18 derivatives with distinct temporal order of activity during mitosis, conferred either by differential phosphorylation inactivation or by anaphase-specific degradation through fusion with the destruction box of cyclin B1. We present evidence that excessive Op18 activity generates chromosomal instability through interference occurring subsequent to the metaphase-to-anaphase transition, which reduces the fidelity of chromosome segregation to spindle poles during anaphase. Similar to uncorrected merotelic attachment, this mechanism evades detection by the spindle assembly checkpoint and thus provides an additional route to chromosomal instability.", "doi": "10.1016/j.yexcr.2010.04.008", "pmid": "20399773", "labels": {"Mikael Sellin": null, "SciLifeLab Fellow": null}, "xrefs": [], "notes": [], "created": "2018-12-03T14:25:42.954Z", "modified": "2022-11-07T11:35:38.102Z"}, {"entity": "publication", "iuid": "9ffacc3005af4a909fc1cb42250055e0", "links": {"self": {"href": "https://publications-affiliated.scilifelab.se/publication/9ffacc3005af4a909fc1cb42250055e0.json"}, "display": {"href": "https://publications-affiliated.scilifelab.se/publication/9ffacc3005af4a909fc1cb42250055e0"}}, "title": "Op18/Stathmin counteracts the activity of overexpressed tubulin-disrupting proteins in a human leukemia cell line.", "authors": [{"family": "Sellin", "given": "Mikael E", "initials": "ME"}, {"family": "Holmfeldt", "given": "Per", "initials": "P"}, {"family": "Stenmark", "given": "Sonja", "initials": "S"}, {"family": "Gullberg", "given": "Martin", "initials": "M"}], "type": "journal article", "published": "2008-04-01", "journal": {"title": "Experimental Cell Research", "issn": "0014-4827", "volume": "314", "issue": "6", "pages": "1367-1377", "issn-l": "0014-4827"}, "abstract": "Op18/stathmin (Op18) is a phosphorylation-regulated and differentially expressed microtubule-destabilizing protein in animal cells. Op18 regulates tubulin monomer-polymer partitioning of the interphase microtubule system and forms complexes with tubulin heterodimers. Recent reports have shown that specific tubulin-folding cofactors and related proteins may disrupt tubulin heterodimers. We therefore investigated whether Op18 protects unpolymerized tubulin from such disruptive activities. Our approach was based on inducible overexpression of two tubulin-disrupting proteins, namely TBCE, which is required for tubulin biogenesis, and E-like, which has been proposed to regulate tubulin turnover and microtubule stability. Expression of either of these proteins was found to cause a rapid degradation of both alpha-tubulin and beta-tubulin subunits of unpolymerized, but not polymeric, tubulin heterodimers. We found that depletion of Op18 by means of RNA interference increased the susceptibility of tubulin to TBCE or E-like mediated disruption, while overexpressed Op18 exerted a tubulin-protective effect. Tubulin protection was shown to depend on Op18 levels, binding affinity, and the partitioning between tubulin monomers and polymers. Hence, the present study reveals that Op18 at physiologically relevant levels functions to preserve the integrity of tubulin heterodimers, which may serve to regulate tubulin turnover rates.", "doi": "10.1016/j.yexcr.2007.12.018", "pmid": "18262179", "labels": {"Mikael Sellin": null, "SciLifeLab Fellow": null}, "xrefs": [{"db": "pii", "key": "S0014-4827(08)00005-0"}], "notes": [], "created": "2020-10-05T15:22:28.689Z", "modified": "2022-11-07T11:35:38.150Z"}], "created": "2018-12-03T14:25:42.968Z", "modified": "2020-11-27T13:12:50.560Z"}