Meiotic telomere clustering is inhibited by colchicine but does not require cytoplasmic microtubules.
نویسندگان
چکیده
Telomere clustering, the defining feature of the bouquet, is an almost universal feature of meiotic prophase, yet its mechanism remains unknown. The microtubule-depolymerizing agent colchicine was found to inhibit bouquet formation. Telomeres in colchicine-treated cells remained scattered in the nuclear periphery, whereas untreated cells exhibited a prominent telomere cluster. Colchicine administered after the bouquet had formed did not affect telomere dispersal. The effect of colchicine on bouquet formation appeared to be separable from its effect on cytoplasmic microtubules; amiprophos methyl, a highly effective plant microtubule-depolymerizing drug, did not affect telomere clustering. Inhibition of bouquet formation was limited to colchicine and the related drug podophyllotoxin out of the variety of microtubule-depolymerizing drugs tested, suggesting that the target involved in bouquet formation has a structural specificity.
منابع مشابه
Reorganization and polarization of the meiotic bouquet-stage cell can be uncoupled from telomere clustering.
Striking cellular reorganizations mark homologous pairing during meiotic prophase. We address the interdependence of chromosomal and cellular polarization during meiotic telomere clustering, the defining feature of the bouquet stage, by examining nuclear positioning and microtubule and nuclear pore reorganization. Polarization of meiotic cellular architecture was coincident with telomere cluste...
متن کاملA Taz1- and Microtubule-Dependent Regulatory Relationship between Telomere and Centromere Positions in Bouquet Formation Secures Proper Meiotic Divisions
During meiotic prophase, telomeres cluster, forming the bouquet chromosome arrangement, and facilitate homologous chromosome pairing. In fission yeast, bouquet formation requires switching of telomere and centromere positions. Centromeres are located at the spindle pole body (SPB) during mitotic interphase, and upon entering meiosis, telomeres cluster at the SPB, followed by centromere detachme...
متن کاملMicrotubule-organizing center formation at telomeres induces meiotic telomere clustering
During meiosis, telomeres cluster and promote homologous chromosome pairing. Telomere clustering requires the interaction of telomeres with the nuclear membrane proteins SUN (Sad1/UNC-84) and KASH (Klarsicht/ANC-1/Syne homology). The mechanism by which telomeres gather remains elusive. In this paper, we show that telomere clustering in fission yeast depends on microtubules and the microtubule m...
متن کاملH2AX regulates meiotic telomere clustering
The histone H2A variant H2AX is phosphorylated in response to DNA double-strand breaks originating from diverse origins, including dysfunctional telomeres. Here, we show that normal mitotic telomere maintenance does not require H2AX. Moreover, H2AX is dispensable for the chromosome fusions arising from either critically shortened or deprotected telomeres. However, H2AX has an essential role in ...
متن کاملHomologous pairing during meiotic prophase is essential for homologous recombination and for chromosome segregation
Homologous pairing during meiotic prophase is essential for homologous recombination and for chromosome segregation during meiosis I; yet, it is largely unknown how homologues approach each other. A chromosomal rearrangement called the telomere bouquet in early meiotic prophase is thought to play a key role in homologous pairing (Scherthan, 2001; Harper et al., 2004). It forms as telomeres clus...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Journal of cell science
دوره 115 Pt 19 شماره
صفحات -
تاریخ انتشار 2002