scholarly journals Involvement of Kif4a in Spindle Formation and Chromosome Segregation in Mouse Oocytes

2018 ◽  
Vol 9 (4) ◽  
pp. 623 ◽  
Author(s):  
Feng Tang ◽  
Meng-Hao Pan ◽  
Yujie Lu ◽  
Xiang Wan ◽  
Yu Zhang ◽  
...  
Keyword(s):  
Chromosome Segregation ◽  
Spindle Formation ◽  
Mouse Oocytes

scholarly journals PLK1 is required for chromosome compaction and microtubule organization in mouse oocytes

2020 ◽  
Vol 31 (12) ◽  
pp. 1206-1217
Author(s):  
Tara M. Little ◽  
Philip W. Jordan
Keyword(s):  
Chromosome Segregation ◽  
Microtubule Organizing Center ◽  
Microtubule Organization ◽  
Spindle Formation ◽  
Bipolar Spindle ◽  
Mouse Oocytes ◽  
Organizing Center ◽  
Meiosis I

By deleting Plk1 in mouse oocytes before meiotic resumption, we show that PLK1 is essential for the formation of condensed bivalent chromosomes, microtubule organizing center fragmentation, liquid-like spindle domain localization, and bipolar spindle formation. Thus, PLK1 coordinates processes that ensure chromosome segregation during meiosis I.

scholarly journals WHAMM is essential for spindle formation and spindle actin polymerization in maturing mouse oocytes

Cell Cycle ◽  
2021 ◽  
pp. 1-11
Author(s):  
Yu-Jin Jo ◽  
Jeongwoo Kwon ◽  
Zhe-Long Jin ◽  
Suk Namgoong ◽  
Taeho Kwon ◽  
...  
Keyword(s):  
Actin Polymerization ◽  
Spindle Formation ◽  
Mouse Oocytes

CENP-A regulates chromosome segregation during the first meiosis of mouse oocytes

2017 ◽  
Vol 37 (3) ◽  
pp. 313-318 ◽  
Author(s):  
Li Li ◽  
Shu-tao Qi ◽  
Qing-yuan Sun ◽  
Shi-ling Chen
Keyword(s):  
Chromosome Segregation ◽  
Mouse Oocytes

Regulation of Microtubule Assembly: The View From The End

2000 ◽  
Vol 6 (S2) ◽  
pp. 80-81
Author(s):  
L. Cassimeris ◽  
C. Spittle ◽  
M. Kratzer
Keyword(s):  
Chromosome Segregation ◽  
Mitotic Spindle ◽  
Dynamic Instability ◽  
Intrinsic Property ◽  
Microtubule Dynamics ◽  
Microtubule Assembly ◽  
Chromosome Movement ◽  
Spindle Formation ◽  
Associated Proteins

The mitotic spindle is responsible for chromosome movement during mitosis. It is composed of a dynamic array of microtubules and associated proteins whose assembly and constant turnover are required for both spindle formation and chromosome movement. Because microtubule assembly and turnover are necessary for chromosome segregation, we are studying how cells regulate microtubule dynamics. Microtubules are polarized polymers composed of tubulin subunits; they assemble by a process of dynamic instability where individual microtubules exist in persistent phases of elongation or rapid shortening with abrupt transitions between these two states. The switch from elongation to shortening is termed catastrophe, and the switch from shortening to elongation, rescue. Although dynamic instability is an intrinsic property of the tubulin subunits, cells use associated proteins to both speed elongation (∼ 10 fold) and regulate transitions.The only protein isolated to date capable of promoting fast polymerization consistent with rates in vivo is XMAP215, a 215 kD protein from Xenopus eggs.

scholarly journals Disturbed chromosome segregation and multipolar spindle formation in a patient with CHAMP1 mutation

2017 ◽  
Vol 5 (5) ◽  
pp. 585-591
Author(s):  
Nobuhiko Okamoto ◽  
Yuki Tsuchiya ◽  
Ichiro Kuki ◽  
Toshiyuki Yamamoto ◽  
Hirotomo Saitsu ◽  
...  
Keyword(s):  
Chromosome Segregation ◽  
Spindle Formation ◽  
Multipolar Spindle

scholarly journals csi2p modulates microtubule dynamics and organizes the bipolar spindle for chromosome segregation

2014 ◽  
Vol 25 (24) ◽  
pp. 3900-3908 ◽  
Author(s):  
Judite Costa ◽  
Chuanhai Fu ◽  
V. Mohini Khare ◽  
Phong T. Tran
Keyword(s):  
Fission Yeast ◽  
Chromosome Segregation ◽  
Spindle Assembly Checkpoint ◽  
Microtubule Dynamics ◽  
High Rate ◽  
Spindle Formation ◽  
Bipolar Spindle ◽  
Eukaryotic Chromosome ◽  
Relative Contribution ◽  
Multiple Phenotypes

Proper chromosome segregation is of paramount importance for proper genetic inheritance. Defects in chromosome segregation can lead to aneuploidy, which is a hallmark of cancer cells. Eukaryotic chromosome segregation is accomplished by the bipolar spindle. Additional mechanisms, such as the spindle assembly checkpoint and centromere positioning, further help to ensure complete segregation fidelity. Here we present the fission yeast csi2+. csi2p localizes to the spindle poles, where it regulates mitotic microtubule dynamics, bipolar spindle formation, and subsequent chromosome segregation. csi2 deletion (csi2Δ) results in abnormally long mitotic microtubules, high rate of transient monopolar spindles, and subsequent high rate of chromosome segregation defects. Because csi2Δ has multiple phenotypes, it enables estimates of the relative contribution of the different mechanisms to the overall chromosome segregation process. Centromere positioning, microtubule dynamics, and bipolar spindle formation can all contribute to chromosome segregation. However, the major determinant of chromosome segregation defects in fission yeast may be microtubule dynamic defects.

Trichlorfon predisposes to aneuploidy and interferes with spindle formation in in vitro maturing mouse oocytes

2004 ◽  
Vol 564 (2) ◽  
pp. 165-178 ◽  
Author(s):  
Suna Cukurcam ◽  
Fengyun Sun ◽  
Ilse Betzendahl ◽  
Ilse-Dore Adler ◽  
Ursula Eichenlaub-Ritter
Keyword(s):  
Spindle Formation ◽  
Mouse Oocytes

scholarly journals Aurora-C Kinase Deficiency Causes Cytokinesis Failure in Meiosis I and Production of Large Polyploid Oocytes in Mice

2010 ◽  
Vol 21 (14) ◽  
pp. 2371-2383 ◽  
Author(s):  
Kuo-Tai Yang ◽  
Shu-Kuei Li ◽  
Chih-Chieh Chang ◽  
Chieh-Ju C. Tang ◽  
Yi-Nan Lin ◽  
...  
Keyword(s):  
Chromosome Segregation ◽  
Female Mouse ◽  
Histone H3 ◽  
Aurora B ◽  
Binding Motif ◽  
Mouse Oocytes ◽  
Microtubule Attachment ◽  
H3 Phosphorylation ◽  
Histone H3 Phosphorylation ◽  
Meiosis I

We previously isolated Aurora-C/Aie1 in a screen for kinases expressed in mouse sperm and eggs. Here, we show the localization of endogenous Aurora-C and examine its roles during female mouse meiosis. Aurora-C was detected at the centromeres and along the chromosome arms in prometaphase I–metaphase I and was concentrated at centromeres at metaphase II, in which Aurora-C also was phosphorylated at Thr171. During the anaphase I–telophase I transition, Aurora-C was dephosphorylated and relocalized to the midzone and midbody. Microinjection of the kinase-deficient Aurora-C (AurC-KD) mRNA into mouse oocytes significantly inhibited Aurora-C activity and caused multiple defects, including chromosome misalignment, abnormal kinetochore–microtubule attachment, premature chromosome segregation, and cytokinesis failure in meiosis I. Furthermore, AurC-KD reduced Aurora-C and histone H3 phosphorylation and inhibited kinetochore localization of Bub1 and BubR1. Similar effects also were observed in the oocytes injected with INCNEP-delIN mRNAs, in which the Aurora-C binding motif was removed. The most dramatic effect observed in AurC-KD–injected oocytes is cytokinesis failure in meiosis I, resulting in producing large polyploid oocytes, a pattern similar to Aurora-C deficiency human spermatozoa. Surprisingly, we detected no Aurora-B protein in mouse oocytes. We propose that Aurora-C, but not Aurora-B, plays essential roles in female mouse meiosis.

scholarly journals Wapl releases Scc1-cohesin and regulates chromosome structure and segregation in mouse oocytes

2020 ◽  
Vol 219 (4) ◽  
Author(s):  
Mariana C.C. Silva ◽  
Sean Powell ◽  
Sabrina Ladstätter ◽  
Johanna Gassler ◽  
Roman Stocsits ◽  
...  
Keyword(s):  
Residence Time ◽  
Chromosome Segregation ◽  
Chromosome Structure ◽  
Somatic Cells ◽  
Cell Types ◽  
Chromosome Organization ◽  
Loop Size ◽  
Mouse Oocytes ◽  
Single Nucleus ◽  
Meiosis I

Cohesin is essential for genome folding and inheritance. In somatic cells, these functions are both mediated by Scc1-cohesin, which in mitosis is released from chromosomes by Wapl and separase. In mammalian oocytes, cohesion is mediated by Rec8-cohesin. Scc1 is expressed but neither required nor sufficient for cohesion, and its function remains unknown. Likewise, it is unknown whether Wapl regulates one or both cohesin complexes and chromosome segregation in mature oocytes. Here, we show that Wapl is required for accurate meiosis I chromosome segregation, predominantly releases Scc1-cohesin from chromosomes, and promotes production of euploid eggs. Using single-nucleus Hi-C, we found that Scc1 is essential for chromosome organization in oocytes. Increasing Scc1 residence time on chromosomes by Wapl depletion leads to vermicelli formation and intra-loop structures but, unlike in somatic cells, does not increase loop size. We conclude that distinct cohesin complexes generate loops and cohesion in oocytes and propose that the same principle applies to all cell types and species.

Sign in / Sign up

Export Citation Format

Share Document