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Full-Text Articles in Medicine and Health Sciences
Stress-Inducible Phosphoprotein 1 Has Unique Cochaperone Activity During Development And Regulates Cellular Response To Ischemia Via The Prion Protein., Flavio H Beraldo, Iaci N Soares, Daniela F Goncalves, Jue Fan, Anu A Thomas, Tiago G Santos, Amro H Mohammad, Martin Roffé, Michele D Calder, Simona Nikolova, Glaucia N Hajj, Andre L Guimaraes, Andre R Massensini, Ian Welch, Dean H Betts, Robert Gros, Maria Drangova, Andrew J Watson, Robert Bartha, Vania F Prado, Vilma R Martins, Marco A M Prado
Stress-Inducible Phosphoprotein 1 Has Unique Cochaperone Activity During Development And Regulates Cellular Response To Ischemia Via The Prion Protein., Flavio H Beraldo, Iaci N Soares, Daniela F Goncalves, Jue Fan, Anu A Thomas, Tiago G Santos, Amro H Mohammad, Martin Roffé, Michele D Calder, Simona Nikolova, Glaucia N Hajj, Andre L Guimaraes, Andre R Massensini, Ian Welch, Dean H Betts, Robert Gros, Maria Drangova, Andrew J Watson, Robert Bartha, Vania F Prado, Vilma R Martins, Marco A M Prado
Obstetrics & Gynaecology Publications
Stress-inducible phosphoprotein 1 (STI1) is part of the chaperone machinery, but it also functions as an extracellular ligand for the prion protein. However, the physiological relevance of these STI1 activities in vivo is unknown. Here, we show that in the absence of embryonic STI1, several Hsp90 client proteins are decreased by 50%, although Hsp90 levels are unaffected. Mutant STI1 mice showed increased caspase-3 activation and 50% impairment in cellular proliferation. Moreover, placental disruption and lack of cellular viability were linked to embryonic death by E10.5 in STI1-mutant mice. Rescue of embryonic lethality in these mutants, by transgenic expression of the …
Culture Medium, Gas Atmosphere And Mapk Inhibition Affect Regulation Of Rna-Binding Protein Targets During Mouse Preimplantation Development., Michele D Calder, Patricia H Watson, Andrew J Watson
Culture Medium, Gas Atmosphere And Mapk Inhibition Affect Regulation Of Rna-Binding Protein Targets During Mouse Preimplantation Development., Michele D Calder, Patricia H Watson, Andrew J Watson
Obstetrics & Gynaecology Publications
During oogenesis, mammalian oocytes accumulate maternal mRNAs that support the embryo until embryonic genome activation. RNA-binding proteins (RBP) may regulate the stability and turnover of maternal and embryonic mRNAs. We hypothesised that varying embryo culture conditions, such as culture medium, oxygen tension and MAPK inhibition, affects regulation of RBPs and their targets during preimplantation development. STAU1, ELAVL1, KHSRP and ZFP36 proteins and mRNAs were detected throughout mouse preimplantation development, whereas Elavl2 mRNA decreased after the two-cell stage. Potential target mRNAs of RBP regulation, Gclc, Slc2a1 and Slc7a1 were detected during mouse preimplantation development. Gclc mRNA was significantly elevated in embryos …
Ouabain Stimulates A Na+/K+-Atpase-Mediated Sfk-Activated Signalling Pathway That Regulates Tight Junction Function In The Mouse Blastocyst., Holly Giannatselis, Michele Calder, Andrew J Watson
Ouabain Stimulates A Na+/K+-Atpase-Mediated Sfk-Activated Signalling Pathway That Regulates Tight Junction Function In The Mouse Blastocyst., Holly Giannatselis, Michele Calder, Andrew J Watson
Obstetrics & Gynaecology Publications
The Na(+)/K(+)-ATPase plays a pivotal role during preimplantation development; it establishes a trans-epithelial ionic gradient that facilitates the formation of the fluid-filled blastocyst cavity, crucial for implantation and successful pregnancy. The Na(+)/K(+)-ATPase is also implicated in regulating tight junctions and cardiotonic steroid (CTS)-induced signal transduction via SRC. We investigated the expression of SRC family kinase (SFK) members, Src and Yes, during preimplantation development and determined whether SFK activity is required for blastocyst formation. Embryos were collected following super-ovulation of CD1 or MF1 female mice. RT-PCR was used to detect SFK mRNAs encoding Src and Yes throughout preimplantation development. SRC and …
Mouse Preimplantation Embryo Responses To Culture Medium Osmolarity Include Increased Expression Of Ccm2 And P38 Mapk Activation., Barry Fong, Patricia H Watson, Andrew J Watson
Mouse Preimplantation Embryo Responses To Culture Medium Osmolarity Include Increased Expression Of Ccm2 And P38 Mapk Activation., Barry Fong, Patricia H Watson, Andrew J Watson
Obstetrics & Gynaecology Publications
BACKGROUND: Mechanisms that confer an ability to respond positively to environmental osmolarity are fundamental to ensuring embryo survival during the preimplantation period. Activation of p38 mitogen-activated protein kinase (MAPK) occurs following exposure to hyperosmotic treatment. Recently, a novel scaffolding protein called Osmosensing Scaffold for MEKK3 (OSM) was linked to p38 MAPK activation in response to sorbitol-induced hypertonicity. The human ortholog of OSM is cerebral cavernous malformation 2 (CCM2). The present study was conducted to investigate whether CCM2 is expressed during mouse preimplantation development and to determine whether this scaffolding protein is associated with p38 MAPK activation following exposure of preimplantation …
Deletion Of The Na/K-Atpase Alpha1-Subunit Gene (Atp1a1) Does Not Prevent Cavitation Of The Preimplantation Mouse Embryo., L C Barcroft, A E Moseley, J B Lingrel, A J Watson
Deletion Of The Na/K-Atpase Alpha1-Subunit Gene (Atp1a1) Does Not Prevent Cavitation Of The Preimplantation Mouse Embryo., L C Barcroft, A E Moseley, J B Lingrel, A J Watson
Obstetrics & Gynaecology Publications
Increases in Na/K-ATPase activity occur concurrently with the onset of cavitation and are associated with increases in Na(+)-pump subunit mRNA and protein expression. We have hypothesized that the alpha1-isozyme of the Na/K-ATPase is required to mediate blastocyst formation. We have tested this hypothesis by characterizing preimplantation development in mice with a targeted disruption of the Na/K-ATPase alpha1-subunit (Atp1a1) using embryos acquired from matings between Atp1a1 heterozygous mice. Mouse embryos homozygous for a null mutation in the Na/K-ATPase alpha1-subunit gene are able to undergo compaction and cavitation. These findings demonstrate that trophectoderm transport mechanisms are maintained in the absence of the …
Sensitivity Of Bovine Blastocyst Gene Expression Patterns To Culture Environments Assessed By Differential Display Rt-Pcr., D R Natale, P A De Sousa, M E Westhusin, A J Watson
Sensitivity Of Bovine Blastocyst Gene Expression Patterns To Culture Environments Assessed By Differential Display Rt-Pcr., D R Natale, P A De Sousa, M E Westhusin, A J Watson
Obstetrics & Gynaecology Publications
The use of culture media to support the development of preimplantation embryos to the blastocyst stage is often associated with detrimental effects on normal development. These effects have been uncovered largely by investigating the phenotypic abnormalities displayed by fetuses and newborns derived from cultured preimplantation embryos. Research to understand the impact of culture on the embryonic developmental programme has focused on embryo metabolism, gene expression and genomic imprinting. We have used differential display RT-PCR to examine culture influences on global transcript pools in bovine embryos. Others have examined culture influences on candidate "marker genes" in cultured murine, ovine and bovine …
Na/K-Atpase-Mediated 86rb+ Uptake And Asymmetrical Trophectoderm Localization Of Alpha1 And Alpha3 Na/K-Atpase Isoforms During Bovine Preattachment Development., D H Betts, L C Barcroft, A J Watson
Na/K-Atpase-Mediated 86rb+ Uptake And Asymmetrical Trophectoderm Localization Of Alpha1 And Alpha3 Na/K-Atpase Isoforms During Bovine Preattachment Development., D H Betts, L C Barcroft, A J Watson
Obstetrics & Gynaecology Publications
This study evaluated Na/K-ATPase alpha 1- and alpha 3-subunit isoform polypeptide expression and localization during bovine preattachment development. Na/K-ATPase cation transport activity from the one-cell to blastocyst stage was also determined by measuring ouabain-sensitive 86Rb+ uptake. Both alpha1- and alpha 3-subunit polypeptides were detected by immunofluorescence to encircle the entire cell margins of each blastomere of inseminated zygotes, cleavage stage embryos, and morulae. Immunofluorescent localization of alpha1-subunit polypeptide in bovine blastocysts revealed an alpha1 immunofluorescence signal confined to the basolateral membrane margins of the trophectoderm and encircling the cell periphery of each inner cell mass (ICM) cell. In contrast, alpha …
A Growth Factor Phenotype Map For Ovine Preimplantation Development., A J Watson, P H Watson, M Arcellana-Panlilio, D Warnes, S K Walker, G A Schultz, D T Armstrong, R F Seamark
A Growth Factor Phenotype Map For Ovine Preimplantation Development., A J Watson, P H Watson, M Arcellana-Panlilio, D Warnes, S K Walker, G A Schultz, D T Armstrong, R F Seamark
Obstetrics & Gynaecology Publications
The reverse transcription-polymerase chain reaction (RT-PCR) was used to determine the patterns of expression for several growth factor ligand and receptor genes during ovine preimplantation development. Transcripts for insulin-like growth factor (IGF)-I, IGF-II, and the receptors for insulin and IGF-I were detected throughout ovine preimplantation development from the 1-cell to the blastocyst stage. Transforming growth factor alpha (TGF alpha) transcripts were also detected throughout ovine preimplantation development. The mRNAs encoding basic fibroblast growth factor (bFGF) were detected in all stages of the ovine preimplantation embryo, although the relative abundance of this transcript consistently decreased from the 1-cell to the blastocyst …
Preimplantation Development Of In Vitro-Matured And In Vitro-Fertilized Ovine Zygotes: Comparison Between Coculture On Oviduct Epithelial Cell Monolayers And Culture Under Low Oxygen Atmosphere., A J Watson, P H Watson, D Warnes, S K Walker, D T Armstrong, R F Seamark
Preimplantation Development Of In Vitro-Matured And In Vitro-Fertilized Ovine Zygotes: Comparison Between Coculture On Oviduct Epithelial Cell Monolayers And Culture Under Low Oxygen Atmosphere., A J Watson, P H Watson, D Warnes, S K Walker, D T Armstrong, R F Seamark
Obstetrics & Gynaecology Publications
The roles of medium composition, serum source, embryo coculture, and culture under low O2 conditions on the development of in vitro-matured and in vitro-fertilized (IVMF) ovine zygotes were investigated in three separate experiments. In the first experiment, the proportion of cocultured IVMF zygotes developing to the blastocyst stage was significantly higher (38.0% vs. 3.5%; p < 0.05) than that of non-cocultured zygotes treated within three embryo culture media (TCM-199 + 10% fetal bovine serum [FBS]; bicarbonate-buffered, glucose-free synthetic oviduct fluid medium [mod-SOFM] + 10% FBS; and bicarbonate-buffered BSA-free Tyrode's salt solution [mod-TALP] + 10% FBS) under a 5% CO2 atmosphere in air. In a second experiment, a significantly higher (p < 0.05) proportion of cocultured zygotes placed in TCM-199 medium survived to the blastocyst stage (37.4% blastocysts vs. 23.4% in mod-SOFM). No significant effect of serum (FBS vs. human serum [HS]) was observed on embryonic development, but coculture was confirmed to exert a significant influence on development to the blastocyst stage. In the final experiment, survival of the embryo under a reduced oxygen (5% CO2:5% O2:90% N2) atmosphere was investigated. In contrast to results in the initial experiments, embryonic survival was significantly higher (p < 0.05) in the non-cocultured treatment groups (21.9% blastocysts vs. 0.4% for cocultured zygotes). Serum source also had a significant (p < 0.05) influence upon the development of non-cocultured zygotes: 32.3% of zygotes cultured with HS progressed to the blastocyst stage vs. 11.5% of zygotes cultured in FBS-supplemented medium. These results have characterized two distinct culture environments, each capable of supporting the development of high frequencies of unselected IVMF zygotes to the blastocyst stage in vitro.