A5052255710- Reproductive Biology and Fertility
- Microtubule and mitosis dynamics
- Sperm and Testicular Function
- Pluripotent Stem Cells Research
- RNA Research and Splicing
- Epigenetics and DNA Methylation
- Prenatal Screening and Diagnostics
- Renal and related cancers
- Genomics and Chromatin Dynamics
- Ubiquitin and proteasome pathways
- Ovarian function and disorders
- Seed Germination and Physiology
- Pancreatic function and diabetes
- Genetics, Aging, and Longevity in Model Organisms
- Plant tissue culture and regeneration
- Cancer-related molecular mechanisms research
- Cancer-related Molecular Pathways
- PI3K/AKT/mTOR signaling in cancer
- Polyamine Metabolism and Applications
- DNA Repair Mechanisms
- CRISPR and Genetic Engineering
- Plant Molecular Biology Research
- Molecular Biology Techniques and Applications
- Animal Genetics and Reproduction
- RNA modifications and cancer
Czech Academy of Sciences, Institute of Animal Physiology and Genetics
2011-2024
Czech Academy of Sciences
1996-2014
Institute of Animal Physiology of the Slovak Academy of Sciences
2003-2012
Kinexus Bioinformatics Corporation (Canada)
2008
University of British Columbia
2008
Charles University
2001
Babraham Institute
1996-2000
Danish Cattle Research Centre
1997
École Normale Supérieure de Lyon
1993-1994
ABSTRACT In this paper, the existence of two A-type cyclins in mouse is demonstrated. adult mouse, expression cyclin A1, which has greatest sequence identity with Xenopus restricted to germ cells. contrast A2, human A and expressed all tissues analysed. order explore function A1 cells, its during meiotic cell cycle associated kinase subunits have been characterised testis. The levels mRNA rise dramatically late pachytene spermatocytes become undetectable soon after completion divisions; thus...
Abstract The fully grown mammalian oocyte is transcriptionally quiescent and utilizes only transcripts synthesized stored during early development. However, we find that an abundant RNA population retained in the nucleus contains specific mRNAs important for meiotic progression. Here show first division, shortly after nuclear envelope breakdown, translational hotspots develop chromosomal area a region was previously surrounded nucleus. These distinct are separated by endoplasmic reticulum...
In this study, butyrolactone I (BL I), a potent and specific inhibitor of cyclin-dependent kinases, was shown to block germinal vesicle (GV) breakdown (GVBD) in bovine oocytes concentration-dependent manner; GVBD almost totally inhibited over the course 24–48 h culture when 100 μM BL included tissue medium 199 containing either polyvinyl alcohol or BSA. Correlated with inhibition failure p34cdc2 kinase mitogen-activated protein (MAP) become activated, it unlikely that directly MAP kinase,...
Aurora kinase A (AURKA), which is a centrosome-localized serine/threonine crucial for cell cycle control, critically involved in centrosome maturation and spindle assembly somatic cells. Active T288 phosphorylated AURKA localizes to the late G2 also spreads minus ends of mitotic microtubules. activates centrosomal CDC25B recruits cyclin B1 centrosomes. We report here functions meiotic mouse oocytes, model system study M transition. Whereas present throughout entire GV-stage oocyte with clear...
Chromosome segregation errors are highly frequent in mammalian female meiosis, and their incidence gradually increases with maternal age. The fate of aneuploid eggs is obviously dependent on the stringency mechanisms for detecting unattached or repairing incorrectly attached kinetochores. In case failure, newly formed embryo will inherit impaired set chromosomes, which have severe consequences its further development. Whether spindle assembly checkpoint (SAC) oocytes capable arresting cell...
In fully grown mouse oocytes, a decrease in cAMP concentration precedes and is linked to CDK1 (cyclin-dependent kinase 1) activation. The molecular mechanism for this coupling, however, not defined. PKB (protein B, also called AKT) implicated activation lower species. During resumption of meiosis starfish MYT1, negative regulator CDK1, phosphorylated by an inhibitory manner. It can imply that involved mammalian oocytes.We monitored during maturation oocytes. phosphorylation preceded GVBD...
Abstract All porcine oocytes cultured 20 hr in medium with 10 μg/ml cycloheximide rested the germinal vesicle (GV) stage but highly condensed bivalents nucleoplasm. When these were washed and control for 2, 4, 6 hr, breakdown (GVBD) was completed 0, 86, 100% of them, respectively. similarly inhibited successively only 2.5 given again enriched (3.5 hr), nearly all them reached late diakinesis again. It means that free this inhibitor protein synthesis GVBD rapidly (4 hr) crucial nuclear...
The tight correlation between mRNA distribution and subsequent protein localization function indicate a major role for within the cell. RNA localization, followed by local translation, presents mechanism spatial temporal gene expression regulation utilized various cell types. However, little is known about translation in mammalian oocyte early embryo. Importantly, fully-grown becomes transcriptionally inactive only utilizes transcripts previously synthesized stored during earlier...
In vitro maturation (IVM) of fully grown mammalian oocytes is characterized by initial germinal vesicle (GV) breakdown and rearrangement microtubule network during the first meiosis (MI), followed extrusion polar body block in metaphase second (MII). Only matured are capable undergoing fertilization initiation zygotic development. These observations mostly based on morphological evaluation; however, molecular events responsible for these processes not known. this study, we have launched...
Fully grown mammalian oocytes utilize transcripts synthetized and stored during earlier development. RNA localization followed by a local translation is mechanism responsible for the regulation of spatial temporal gene expression. Here we show that mouse oocyte contains 3 forms cap-dependent translational repressor expressed on mRNA level: 4E-BP1, 4E-BP2 4E-BP3. However, only 4E-BP1 present as protein in oocytes, it becomes inactivated phosphorylation after nuclear envelope breakdown such...
Meiotic maturation of mammalian oocytes (transition from prophase I to metaphase II) is accompanied by complex changes in the protein phosphorylation pattern. At least two major kinases are involved these events; namely, cdc2 kinase and mitogen-activated (MAP) kinase, because inhibition arrest germinal vesicle (GV) stage. We show that during meiotic bovine oocytes, translation initiation factor, eIF4E (the cap binding protein), gradually becomes phosphorylated. This substantial begins at...
The aim of this study was to investigate the involvement serine/threonine protein kinase AKT (also called B) in control meiosis porcine denuded oocytes (DOs) matured vitro. Western blot analysis revealed that two principal phosphorylation sites, Ser473 and Thr308, are phosphorylated at different stages meiosis. In freshly isolated germinal vesicle (GV)-stage DOs, already phosphorylated. After onset oocyte maturation, intensity increased, however, which declined sharply when DOs underwent GV...
Translation is critical for development as transcription in the oocyte and early embryo silenced. To illustrate translational changes during meiosis consecutive two mitoses of embryo, we performed a genome-wide translatome analysis. Acquired data showed significant uniform activation key initiation elongation axes specific to M-phases. Although global protein synthesis decreases M-phases, translation activity increases uniformly fluctuating manner, leading qualitative regulation via...
It is generally accepted that mammalian oocytes are frequently suffering from chromosome segregation errors during meiosis I, which have severe consequences, including pregnancy loss, developmental disorders and mental retardation. In a search for physiologically more relevant model than rodent to study this phenomenon, we employed comparative genomic hybridization (CGH), combined with whole genome amplification (WGA), the frequency of aneuploidy in porcine oocytes, rare cells obtained aged...
Meiotic maturation of oocyte relies on pre-synthesised maternal mRNA, the translation which is highly coordinated in space and time. Here, we provide a detailed polysome profiling protocol that demonstrates combination sucrose gradient ultracentrifugation small SW55Ti tubes with qRT-PCR-based quantification 18S 28S rRNAs fractionated profile. This newly optimised method, named Scarce Sample Polysome Profiling (SSP-profiling), suitable for both scarce conventional sample sizes compatible...