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Obstetrics & Gynaecology Publications

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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 Sep 2013

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 …


Embryo Collection Induces Transient Activation Of Xbp1 Arm Of The Er Stress Response While Embryo Vitrification Does Not., Tamara Abraham, Christopher L Pin, Andrew J Watson May 2012

Embryo Collection Induces Transient Activation Of Xbp1 Arm Of The Er Stress Response While Embryo Vitrification Does Not., Tamara Abraham, Christopher L Pin, Andrew J Watson

Obstetrics & Gynaecology Publications

Embryo cryopreservation has become a standard procedure in the practice of assisted reproduction. While routinely performed in IVF labs, the effects of embryo vitrification on the molecular mechanisms governing preimplantation development remain largely unknown. The endoplasmic reticulum stress (ER stress) response is an evolutionary conserved mechanism that cells employ to manage ER stress. ER stress can be defined as an imbalance between protein synthesis and secretion within the ER. The primary focus of this study was to investigate whether standard embryo manipulations, including embryo collection, culture and vitrification, result in activation of the ER stress pathway in vitro and to …


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 Nov 2011

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 Jan 2011

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 …


Bovine Oocytes And Early Embryos Express Staufen And Elavl Rna-Binding Proteins., M D Calder, P Madan, A J Watson May 2008

Bovine Oocytes And Early Embryos Express Staufen And Elavl Rna-Binding Proteins., M D Calder, P Madan, A J Watson

Obstetrics & Gynaecology Publications

RNA-binding proteins (RBP) influence RNA editing, localization, stability and translation and may contribute to oocyte developmental competence by regulating the stability and turnover of oogenetic mRNAs. The expression of Staufen 1 and 2 and ELAVL1, ELAVL2 RNA-binding proteins during cow early development was characterized. Cumulus-oocyte complexes were collected from slaughterhouse ovaries, matured, inseminated and subjected to embryo culture in vitro. Oocyte or preimplantation embryo pools were processed for RT-PCR and whole-mount immunofluorescence analysis of mRNA expression and protein distribution. STAU1 and STAU2 and ELAVL1 mRNAs and proteins were detected throughout cow preimplantation development from the germinal vesicle (GV) oocyte to …


Na/K-Atpase Beta1 Subunit Expression Is Required For Blastocyst Formation And Normal Assembly Of Trophectoderm Tight Junction-Associated Proteins., Pavneesh Madan, Keeley Rose, Andrew J Watson Apr 2007

Na/K-Atpase Beta1 Subunit Expression Is Required For Blastocyst Formation And Normal Assembly Of Trophectoderm Tight Junction-Associated Proteins., Pavneesh Madan, Keeley Rose, Andrew J Watson

Obstetrics & Gynaecology Publications

Na/K-ATPase plays an important role in mediating blastocyst formation. Despite the expression of multiple Na/K-ATPase alpha and beta isoforms during mouse preimplantation development, only the alpha1 and beta1 isoforms have been localized to the basolateral membrane regions of the trophectoderm. The aim of the present study was to selectively down-regulate the Na/K-ATPase beta1 subunit employing microinjection of mouse 1 cell zygotes with small interfering RNA (siRNA) oligos. Experiments comprised of non-injected controls and two groups microinjected with either Stealthtrade mark Na/K-ATPase beta1 subunit oligos or nonspecific Stealthtrade mark siRNA as control. Development to the 2-, 4-, 8-, and 16-cell and …


Regulation Of Blastocyst Formation., A J Watson, L C Barcroft May 2001

Regulation Of Blastocyst Formation., A J Watson, L C Barcroft

Obstetrics & Gynaecology Publications

Preimplantation or pre-attachment development encompasses the "free"-living period of mammalian embryogenesis, which directs development of the zygote through to the blastocyst stage. Blastocyst formation is essential for implantation, establishment of pregnancy and is a principal determinant of embryo quality prior to embryo transfer. Cavitation (blastocyst formation) is driven by the expression of specific sets of gene products that direct the acquisition of cell polarity within the trophectoderm, which is both the first epithelium of development and the outer cell layer encircling the inner cell mass of the blastocyst. Critical gene families controlling these events include: the E-cadherin-catenin cell adhesion family, …


Effects Of Superovulated Heifer Diet Type And Quantity On Relative Mrna Abundances And Pyruvate Metabolism In Recovered Embryos., C Wrenzycki, P De Sousa, E W Overström, R T Duby, D Herrmann, A J Watson, H Niemann, D O'Callaghan, M P Boland Jan 2000

Effects Of Superovulated Heifer Diet Type And Quantity On Relative Mrna Abundances And Pyruvate Metabolism In Recovered Embryos., C Wrenzycki, P De Sousa, E W Overström, R T Duby, D Herrmann, A J Watson, H Niemann, D O'Callaghan, M P Boland

Obstetrics & Gynaecology Publications

This study investigated the effects of quantity and type of diet fed to superovulated donor heifers on molecular and metabolic indices of embryonic development. These effects included the relative abundances of mRNAs for the alpha 1 subunit of Na/K-ATPase and the antioxidant enzyme Cu/Zn-SOD, as well as pyruvate utilization in bovine morulae and blastocysts developed in vivo. Heifers were fed a daily ration of either grass silage and a citrus-beet pulp-based concentrate or grass silage and a barley-based concentrate for 116 days, both at 3 kg per day or ad libitum. In embryos derived from heifers fed the pulp-based diets, …


Igf Paracrine And Autocrine Interactions Between Conceptus And Oviduct., A J Watson, M E Westhusin, Q A Winger Jan 1999

Igf Paracrine And Autocrine Interactions Between Conceptus And Oviduct., A J Watson, M E Westhusin, Q A Winger

Obstetrics & Gynaecology Publications

Development in vitro is influenced by embryo density, serum, somatic cell co-culture and the production of 'embryotrophic' paracrine and autocrine factors. Research in our laboratory has focussed principally on the insulin-like growth factor (IGF) family. We have demonstrated that pre-attachment bovine and ovine embryos express mRNAs encoding a number of growth factor ligand and receptor genes including all members of the IGF ligand and receptor family throughout this developmental interval. In addition, early embryos express mRNAs encoding IGF-binding proteins (IGFBPs) 2-5 from the one-cell to the blastocyst stage and IGFBP5 mRNA at the blastocyst stage. Cultured bovine blastocysts release up …


Transient Expression Of A Translation Initiation Factor Is Conservatively Associated With Embryonic Gene Activation In Murine And Bovine Embryos., P A De Sousa, A J Watson, R M Schultz Oct 1998

Transient Expression Of A Translation Initiation Factor Is Conservatively Associated With Embryonic Gene Activation In Murine And Bovine Embryos., P A De Sousa, A J Watson, R M Schultz

Obstetrics & Gynaecology Publications

In the present study the abundance of mRNAs for eukaryotic translation initiation factors eIF-1A (formerly known as eIF-4C), -2alpha, -4A, -4E, and -5 was examined in in vivo-derived mouse embryos throughout preimplantation development using a semiquantitative reverse transcription-polymerase chain reaction assay. Although the mRNA profile for each gene is unique, only mRNA for eIF-1A transiently increases during embryonic gene activation (EGA) at the 2-cell stage, and this was confirmed by an independent hybridization-based assay. In in vitro-developed bovine embryos, mRNA for eIF-1A was transiently detected at the 8-cell stage, when the major activation of the genome occurs in this species. …


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 May 1998

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 …


Bovine Oviductal And Embryonic Insulin-Like Growth Factor Binding Proteins: Possible Regulators Of "Embryotrophic" Insulin-Like Growth Factor Circuits., Q A Winger, P De Los Rios, V K Han, D T Armstrong, D J Hill, A J Watson Jun 1997

Bovine Oviductal And Embryonic Insulin-Like Growth Factor Binding Proteins: Possible Regulators Of "Embryotrophic" Insulin-Like Growth Factor Circuits., Q A Winger, P De Los Rios, V K Han, D T Armstrong, D J Hill, A J Watson

Obstetrics & Gynaecology Publications

Bovine oviductal monolayer and vesicle primary cultures express insulin-like growth factor (IGF)-I and -II mRNAs and polypeptides. Early bovine embryos also express IGF-I, IGF-II, IGF-I receptor, IGF-II receptor, and insulin receptor mRNAs. This study reports the expression of IGF binding protein (IGFBP) mRNAs and polypeptides in bovine oviduct primary cultures and IGFBP mRNAs in preattachment embryos. Release of immunoreactive IGF-I and IGF-II by oviduct cultures and bovine blastocysts was also determined. IGFBP-2, -3, -4, and -5 transcripts were observed in oviduct primary cultures throughout an 8-day interval. IGFBP-1 and -6 mRNAs were consistently not detected in the oviduct. Messenger RNAs …