| Autor: |
Furuta, Tokiko, Tuck, Simon, Kirchner, Jay, Koch, Bryan, Auty, Roy, Kitagawa, Risa, Rose, Ann M., Greenstein, David |
| Zdroj: |
Molecular Biology of the Cell; April 2000, Vol. 11 Issue: 4 p1401-1419, 19p |
| Abstrakt: |
Here we show that emb-30is required for metaphase-to-anaphase transitions during meiosis and mitosis inCaenorhabditiselegans. Germline-specificemb-30mutant alleles block the meiotic divisions. Mutant oocytes, fertilized by wild-type sperm, set up a meiotic spindle but do not progress to anaphase I. As a result, polar bodies are not produced, pronuclei fail to form, and cytokinesis does not occur. Severe-reduction-of-function emb-30alleles (class I alleles) result in zygotic sterility and lead to germline and somatic defects that are consistent with an essential role in promoting the metaphase-to-anaphase transition during mitosis. Analysis of the vulval cell lineages in these emb-30(class I)mutant animals suggests that mitosis is lengthened and eventually arrested when maternally contributed emb-30becomes limiting. By further reducing maternal emb-30function contributed to class I mutant animals, we show that emb-30is required for the metaphase-to-anaphase transition in many, if not all, cells. Metaphase arrest in emb-30mutants is not due to activation of the spindle assembly checkpoint but rather reflects an essential emb-30requirement for M-phase progression. A reduction in emb-30activity can suppress the lethality and sterility caused by a null mutation in mdf-1, a component of the spindle assembly checkpoint machinery. This result suggests that delaying anaphase onset can bypass the spindle checkpoint requirement for normal development. Positional cloning established thatemb-30encodes the likely C. elegansorthologue of APC4/Lid1, a component of the anaphase-promoting complex/cyclosome, required for the metaphase-to-anaphase transition. Thus, the anaphase-promoting complex/cyclosome is likely to be required for all metaphase-to-anaphase transitions in a multicellular organism. |
| Databáze: |
Supplemental Index |
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