Polo-like kinase 1 (Plk1) is pivotal for proper mitotic progression, its targeting activity is regulated by precise subcellular positioning and phosphorylation. Here we assessed the protein expression, subcellular localization and possible functions of phosphorylated Plk1 (pPlk1(Ser137) and pPlk1(Thr210)) in mouse oocytes during meiotic division. Western blot analysis revealed a peptide of pPlk1(Ser137) with high and stable expression from germinal vesicle (GV) until metaphase II (MII), while pPlk1(Thr210) was detected as one large single band at GV stage and 2 small bands after germinal vesicle breakdown (GVBD), which maintained stable up to MII. Immunofluorescence analysis showed pPlk1(Ser137) was colocalized with microtubule organizing center (MTOC) proteins, γ-tubulin and pericentrin, on spindle poles, concomitantly with persistent concentration at centromeres and dynamic aggregation between chromosome arms. Differently, pPlk1(Thr210) was persistently distributed across the whole body of chromosomes after meiotic resumption. The specific Plk1 inhibitor, BI2536, repressed pPlk1(Ser137) accumulation at MTOCs and between chromosome arms, consequently disturbed γ-tubulin and pericentrin recruiting to MTOCs, destroyed meiotic spindle formation, and delayed REC8 cleavage, therefore arresting oocytes at metaphase I (MI) with chromosome misalignment. BI2536 completely reversed the premature degradation of REC8 and precocious segregation of chromosomes induced with okadaic acid (OA), an inhibitor to protein phosphatase 2A. Additionally, the protein levels of pPlk1(Ser137) and pPlk1(Thr210), as well as the subcellular distribution of pPlk1(Thr210), were not affected by BI2536. Taken together, our results demonstrate that Plk1 activity is required for meiotic spindle assembly and REC8 cleavage, with pPlk1(Ser137) is the action executor, in mouse oocytes during meiotic division.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4825778 | PMC |
| http://dx.doi.org/10.1080/15384101.2015.1100770 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
ZAR1/2-Regulated Epigenetic Modifications are Essential for Age-Associated Oocyte Quality Maintenance and Zygotic Activation.
Adv Sci (Weinh)
January 2025
Department of Obstetrics and Gynecology, Zhejiang Key Laboratory of Precise Protection and Promotion of Fertility, Zhejiang Provincial Clinical Research Center for Reproductive Health and Disease, Assisted Reproduction Unit, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, 310016, China.
The developmental competence and epigenetic progression of oocytes gradually become dysregulated with increasing maternal age. However, the mechanisms underlying age-related epigenetic regulation in oocytes remain poorly understood. Zygote arrest proteins 1 and 2 (ZAR1/2) are two maternal factors with partially redundant roles in maintaining oocyte quality, mainly known by regulating mRNA stability.
View Article and Find Full Text PDFTranscriptome and DNA methylation profiling during the NSN to SN transition in mouse oocytes.
BMC Mol Cell Biol
January 2025
Epigenetics Programme, Babraham Institute, Cambridge, CB22 3AT, UK.
Background: During the latter stages of their development, mammalian oocytes under dramatic chromatin reconfiguration, transitioning from a non-surrounded nucleolus (NSN) to a surrounded nucleolus (SN) stage, and concomitant transcriptional silencing. Although the NSN-SN transition is known to be essential for developmental competence of the oocyte, less is known about the accompanying molecular changes. Here we examine the changes in the transcriptome and DNA methylation during the NSN to SN transition in mouse oocytes.
View Article and Find Full Text PDFCALB1 and RPL23 Are Essential for Maintaining Oocyte Quality and Function During Aging.
Aging Cell
January 2025
State Key Laboratory of Animal Biotech Breeding, National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Beijing, China.
With advancing age, significant changes occur in the female reproductive system, the most notable of which is the decline in oocyte quality, a key factor affecting female fertility. However, the mechanisms underlying oocyte aging remain poorly understood. In this study, we obtained oocytes from aged and young female mice and performed single-cell transcriptome sequencing, comparing our findings with existing proteomic analyses.
View Article and Find Full Text PDFA phosphate-binding pocket in cyclin B3 is essential for XErp1/Emi2 degradation in meiosis I.
EMBO Rep
January 2025
Department of Biology, University of Konstanz, 78457, Konstanz, Germany.
To ensure the correct euploid state of embryos, it is essential that vertebrate oocytes await fertilization arrested at metaphase of meiosis II. This MII arrest is mediated by XErp1/Emi2, which inhibits the ubiquitin ligase APC/C (anaphase-promoting complex/cyclosome). Cyclin B3 in complex with Cdk1 (cyclin-dependent kinase 1) is essential to prevent an untimely arrest of vertebrate oocytes in meiosis I by targeting XErp1/Emi2 for degradation.
View Article and Find Full Text PDFMARTRE family proteins negatively regulate CCR4-NOT activity to protect poly(A) tail length and promote translation of maternal mRNA.
Nat Commun
January 2025
Key Laboratory of Epigenetic Regulation and Intervention, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.
Article Synopsis
- The study focuses on the role of a newly discovered protein family called MARTRE in regulating the poly(A) tail length of maternal mRNA during early embryo development in mice.
- MARTRE proteins inhibit the deadenylase CCR4-NOT, helping to maintain longer poly(A) tails and enhance mRNA translation efficiency.
- Deleting the Martre genes leads to shortened poly(A) tails, reduced mRNA translation, and delays in early embryonic development, emphasizing the importance of MARTRE in the translation of maternal mRNA.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!