Characterization of spindle assembly checkpoint in Xenopus egg extracts

Chen, Rey‐Huei; Murray, Andrew W.

doi:10.1016/s0076-6879(97)83045-5

Cited by 17 publications

(16 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Oocytes were stimulated for maturation with 3 ϫ 10 Ϫ6 M of progesterone at 21°C and GVBD was monitored by the appearance of the white spot. Every hour after stimulation, oocytes were collected by groups of 10, and the extracts were prepared with the extraction buffer (EB: 80 mM ␤-glycerophosphate, pH 7.5; 20 mM EGTA; 15 mM MgCl 2 ; 1 mM dithiothreitol) as described previously (34). Proteases inhibitors were added to the lysate, centrifuged for 30 min at 15,000 ϫ g, and frozen at Ϫ80°C until processed.…”

Section: Methodsmentioning

confidence: 99%

Phosphorylation of Maskin by Aurora-A Participates in the Control of Sequential Protein Synthesis during Xenopus laevis Oocyte Maturation

Pascreau

Delcros

Cremet

et al. 2005

Journal of Biological Chemistry

View full text Add to dashboard Cite

At the end of oogenesis, Xenopus laevis stage VI oocytes are arrested at the G 2 /M transition (prophase) waiting for progesterone to release the block and begin maturation. Progesterone triggers a cascade of phosphorylation events such as a decrease of pK a and an increase of maturating-promoting factor activity. Progression through meiosis was controlled by the sequential synthesis of several proteins. For instance, the MAPK kinase kinase c-Mos is the very first protein to be produced, whereas cyclin B1 appears only after meiosis I. After the meiotic cycles, the oocyte arrests at metaphase of meiosis II with an elevated c-Mos kinase activity (cytostatic factor). By using a two-hybrid screen, we have identified maskin, a protein involved in the control of mRNA sequential translation, as a binding partner of Aurora-A, a protein kinase necessary for oocyte maturation. Here we showed that, in vitro, Aurora-A directly binds to maskin and that both proteins can be co-immunoprecipitated from oocyte extracts, suggesting that they do associate in vivo. We also demonstrated that Aurora-A phosphorylates maskin on a Ser residue conserved in transforming acidic coiled coil proteins from Drosophila to human. When the phosphorylation of this Ser was inhibited in vivo by microinjection of synthetic peptides that mimic the maskin-phosphorylated sequence, we observed a premature maturation. Under these conditions, proteins such as cyclin B1 and Cdc6, which are normally detected only in meiosis II, were massively produced in meiosis I before the occurrence of the nuclear envelope breakdown. This result strongly suggests that phosphorylation of maskin by Aurora-A prevents meiosis II proteins from being produced during meiosis I.

show abstract

Section: Methodsmentioning

confidence: 99%

Phosphorylation of Maskin by Aurora-A Participates in the Control of Sequential Protein Synthesis during Xenopus laevis Oocyte Maturation

Pascreau

Delcros

Cremet

et al. 2005

Journal of Biological Chemistry

View full text Add to dashboard Cite

show abstract

“…Extract samples were then thawed by the addition of 9 l of H1 buffer including [␥-32 P]ATP (Chen and Murray, 1997) and incubated for 10 min at room temperature. Reactions were stopped by adding Laemmli gel sample buffer and analyzed by SDS-PAGE.…”

Section: H1 Kinase Assaymentioning

confidence: 99%

“…Moreover, despite the fact that kinetochore localization of BubR1 clearly seems to be regulated by Aurora B, there are contradictory results concerning the regulation by this kinase of the localization of CENP-E and Mad2 at the centromeres (Kallio et al, 2002b;Ditchfield et al, 2003;Hauf et al, 2003). To determine the interdependence network of Aurora B with the other checkpoint components, we took advantage of the techniques of immunodepletion and rescue of different spindle checkpoint proteins developed in Xenopus extracts obtained from metaphase II-arrested eggs (CSF extracts) (Chen and Murray, 1997), and we studied the implication of Aurora B in the regulation of the kinetochore localization of Mps1, Bub1, CENP-E, Bub3, Mad1, and Mad2 under spindle checkpoint conditions. To that, we supplemented Aurora B-depleted CSF extracts with nocodazole and 9000 sperm nuclei per microliter of extract.…”

Section: Aurora B/incenp Is Required For the Maintenance Of Thementioning

confidence: 99%

Kinetochore Localization of Spindle Checkpoint Proteins: Who Controls Whom?

Vigneron

Prieto

Bernis

et al. 2004

MBoC

181

187

View full text Add to dashboard Cite

The spindle checkpoint prevents anaphase onset until all the chromosomes have successfully attached to the spindle microtubules. The mechanisms by which unattached kinetochores trigger and transmit a primary signal are poorly understood, although it seems to be dependent at least in part, on the kinetochore localization of the different checkpoint components. By using protein immunodepletion and mRNA translation in Xenopus egg extracts, we have studied the hierarchic sequence and the interdependent network that governs protein recruitment at the kinetochore in the spindle checkpoint pathway. Our results show that the first regulatory step of this cascade is defined by Aurora B/INCENP complex. Aurora B/INCENP controls the activation of a second regulatory level by inducing at the kinetochore the localization of Mps1, Bub1, Bub3, and CENP-E. This localization, in turn, promotes the recruitment to the kinetochore of Mad1/Mad2, Cdc20, and the anaphase promoting complex (APC). Unlike Aurora B/INCENP, Mps1, Bub1, and CENP-E, the downstream checkpoint protein Mad1 does not regulate the kinetochore localization of either Cdc20 or APC. Similarly, Cdc20 and APC do not require each other to be localized at these chromosome structures. Thus, at the last step of the spindle checkpoint cascade, Mad1/Mad2, Cdc20, and APC are recruited at the kinetochores independently from each other.

show abstract

“…Cdc2 kinase activity was measured using histone H1 as substrate as described previously (Chen & Murray 1997, Abrieu et al 2001.…”

Section: Cdc2 Kinase Assaymentioning

confidence: 99%

Histone deacetylase activity is necessary for chromosome condensation during meiotic maturation in Xenopus laevis

Magnaghi-Jaulin

Jaulin

2006

Chromosome Res

View full text Add to dashboard Cite

Chromosome condensation is thought to be an essential step for the faithful transmission of genetic information during cellular division or gamete formation. The folding of DNA into metaphase chromosomes and its partition during the cell cycle remains a fundamental cellular process that, at the molecular level, is poorly understood. Particularly, the role of histone deacetylase (HDAC) activities in establishing and maintaining meiotic metaphase chromosome condensation has been little documented. In order to better understand how metaphase chromosome condensation is achieved during meiosis, we explored, in vivo, the consequences of HDAC activities inhibition in a Xenopus oocyte model. Our results show that deacetylase activity plays a crucial role in chromosome condensation. This activity is necessary for correct chromosome condensation since the earlier stages of meiosis, but dispensable for meiosis progression, meiosis exit and mitosis entry. We show that HDAC activity correlates with chromosome condensation, being higher when chromosomes are fully condensed and lower during interphase, when chromosomes are decondensed. In addition, we show that, unlike histone H4, Xenopus maternal histone H3 is stored in the oocyte as a hypoacetylated form and is rapidly acetylated when the oocyte exits meiosis.

show abstract

Characterization of spindle assembly checkpoint in Xenopus egg extracts

Cited by 17 publications

References 28 publications

Phosphorylation of Maskin by Aurora-A Participates in the Control of Sequential Protein Synthesis during Xenopus laevis Oocyte Maturation

Phosphorylation of Maskin by Aurora-A Participates in the Control of Sequential Protein Synthesis during Xenopus laevis Oocyte Maturation

Kinetochore Localization of Spindle Checkpoint Proteins: Who Controls Whom?

Histone deacetylase activity is necessary for chromosome condensation during meiotic maturation in Xenopus laevis

Contact Info

Product

Resources

About