title: 2,5-Hexanedione-treated tubulin microinjected into sea urchin zygotes induces mitotic abnormalities.
abstract: Zygotes of Lytechinus pictus and Lytechinus variegatus were microinjected with 2,5-hexanedione (2,5-HD)-treated tubulin prior to the first mitotic cycle. Mitotic spindles were small with a well-defined metaphase plate, but poor birefringence and poor astral development. Abnormalities were observed in chromosome movement at anaphase and cytokinesis. Neither microinjections of untreated tubulin or 3-acetyl-2,5-hexanedione-treated tubulin, nor incubation of zygotes in 2,5-HD-containing sea water produced abnormalities. The results can be explained in terms of the nondissociating properties of 2,5-HD-treated tubulin. 2,5-HD-treated tubulin dissociates slowly from microtubules, a property which, besides favoring the formation of stable microtubules, allows this tubulin to induce microtubule assembly when present in substoichiometric amounts. These characteristics have been implicated as a cause of 2,5-HD-induced Sertoli cell dysfunction. The effect of 2,5-HD-treated tubulin on microtubule dynamics in sea urchin zygotes may bear similarities to the effects of 2,5-HD treatment in vivo on Sertoli cell microtubules.
authors.affiliation: Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island 02912.
authors.forename: T M
authors.initials: TM
authors.lastname: Sioussat
authors.forename: F J
authors.initials: FJ
authors.lastname: Miller
authors.forename: K
authors.initials: K
authors.lastname: Boekelheide
mesh_terms: D000818:Animals; D006588:Hexanones / Q000494:pharmacology*; D007659:Ketones / Q000494:pharmacology*; D008845:Microinjections; D008938:Mitosis / Q000187:drug effects*; D010063:Ovum; D012617:Sea Urchins; D012623:Seawater; D014404:Tubulin / Q000008:administration & dosage / Q000502:physiology*; D015053:Zygote / Q000187:drug effects*
chemical_list: D006588:Hexanones; D007659:Ketones; D014404:Tubulin; C011269:2,5-hexanedione