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Full-Text Articles in Medicine and Health Sciences
P38 Mapk Regulates Cavitation And Tight Junction Function In The Mouse Blastocyst., Christine E Bell, Andrew J Watson
P38 Mapk Regulates Cavitation And Tight Junction Function In The Mouse Blastocyst., Christine E Bell, Andrew J Watson
Obstetrics & Gynaecology Publications
UNLABELLED: Blastocyst formation is essential for implantation and maintenance of pregnancy and is dependent on the expression and coordinated function of a series of proteins involved in establishing and maintaining the trans-trophectoderm ion gradient that enables blastocyst expansion. These consist of Na/K-ATPase, adherens junctions, tight junctions (TJ) and aquaporins (AQP). While their role in supporting blastocyst formation is established, the intracellular signaling pathways that coordinate their function is unclear. The p38 MAPK pathway plays a role in regulating these proteins in other cell types and is required for embryo development at the 8-16 cell stage, but its role has not …
Snai1 And Snai2 Are Asymmetrically Expressed At The 2-Cell Stage And Become Segregated To The Te In The Mouse Blastocyst., Christine E Bell, Andrew J Watson
Snai1 And Snai2 Are Asymmetrically Expressed At The 2-Cell Stage And Become Segregated To The Te In The Mouse Blastocyst., Christine E Bell, Andrew J Watson
Obstetrics & Gynaecology Publications
SNAI1 and SNAI2 are transcription factors that initiate Epithelial-to-Mesenchymal cell transitions throughout development and in cancer metastasis. Here we show novel expression of SNAI1 and SNAI2 throughout mouse preimplantation development revealing asymmetrical localization of both SNAI1 and SNAI2 in individual blastomeres beginning at the 2-cell stage through to the 8-cell stage where SNAI1 and SNAI2 are then only detected in outer cells and not inner cells of the blastocyst. This study implicates SNAI1 and SNAI2 in the lineage segregation of the trophectoderm and inner cell mass, and provides new insight into these oncogenes.
Genomic Rna Profiling And The Programme Controlling Preimplantation Mammalian Development., Christine E Bell, Michele D Calder, Andrew J Watson
Genomic Rna Profiling And The Programme Controlling Preimplantation Mammalian Development., Christine E Bell, Michele D Calder, Andrew J Watson
Obstetrics & Gynaecology Publications
Preimplantation development shifts from a maternal to embryonic programme rapidly after fertilization. Although the majority of oogenetic products are lost during the maternal to embryonic transition (MET), several do survive this interval to contribute directly to supporting preimplantation development. Embryonic genome activation (EGA) is characterized by the transient expression of several genes that are necessary for MET, and while EGA represents the first major wave of gene expression, a second mid-preimplantation wave of transcription that supports development to the blastocyst stage has been discovered. The application of genomic approaches has greatly assisted in the discovery of stage specific gene expression …
Preimplantation Embryo Programming: Transcription, Epigenetics, And Culture Environment., Veronique Duranthon, Andrew J Watson, Patrick Lonergan
Preimplantation Embryo Programming: Transcription, Epigenetics, And Culture Environment., Veronique Duranthon, Andrew J Watson, Patrick Lonergan
Obstetrics & Gynaecology Publications
Preimplantation development directs the formation of an implantation- or attachment-competent embryo so that metabolic interactions with the uterus can occur, pregnancy can be initiated, and fetal development can be sustained. The preimplantation embryo exhibits a form of autonomous development fueled by products provided by the oocyte and also from activation of the embryo's genome. Despite this autonomy, the preimplantation embryo is highly influenced by factors in the external environment and in extreme situations, such as those presented by embryo culture or nuclear transfer, the ability of the embryo to adapt to the changing environmental conditions or chromatin to become reprogrammed …
Pp2cdelta (Ppm1d, Wip1), An Endogenous Inhibitor Of P38 Mapk, Is Regulated Along With Trp53 And Cdkn2a Following P38 Mapk Inhibition During Mouse Preimplantation Development., Jenny A Hickson, Barry Fong, Patricia H Watson, Andrew J Watson
Pp2cdelta (Ppm1d, Wip1), An Endogenous Inhibitor Of P38 Mapk, Is Regulated Along With Trp53 And Cdkn2a Following P38 Mapk Inhibition During Mouse Preimplantation Development., Jenny A Hickson, Barry Fong, Patricia H Watson, Andrew J Watson
Obstetrics & Gynaecology Publications
Preimplantation embryos utilize mitogen-activated protein kinase signaling (MAPK) pathways to relay signals from the external environment to prepare appropriate responses and adaptations to a changing milieu. It is therefore important to investigate how MAPK pathways are regulated during preimplantation development. This study was conducted to investigate whether PP2Cdelta (Ppm1d, WIP1) is expressed during mouse preimplantation development and to determine the influences of p38 MAPK inhibition on expression of Trp53 (p53), Ppm1d, (WIP1), and Cdkn2a (p16) during mouse preimplantation development. Our results indicate that Trp53, Ppm1d, and Cdkn2a mRNAs and TRP53 and PP2Cdelta proteins are expressed throughout mouse preimplantation development. Treatment …
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
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 …
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 …
Regulation Of Blastocyst Formation., A J Watson, L C Barcroft
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, …
Differential Involvement Of Na(+),K(+)-Atpase Isozymes In Preimplantation Development Of The Mouse., D J Macphee, D H Jones, K J Barr, D H Betts, A J Watson, G M Kidder
Differential Involvement Of Na(+),K(+)-Atpase Isozymes In Preimplantation Development Of The Mouse., D J Macphee, D H Jones, K J Barr, D H Betts, A J Watson, G M Kidder
Obstetrics & Gynaecology Publications
Na(+),K(+)-ATPase plays an essential role in mammalian blastocoel formation (cavitation) by driving trans-epithelial sodium transport. Previously, the alpha1 and beta1 subunit isoforms of this enzyme were identified in preimplantation mouse embryos and were assumed to be responsible for this function. Here we show that mRNAs encoding an additional alpha subunit isoform (alpha3) and the remaining two beta subunit isoforms are also present in preimplantation embryos. Whereas alpha3 mRNA accumulates between the four-cell and the blastocyst stages and thus results from embryonic transcription, the same could not be demonstrated for beta2 and beta3 mRNAs. Immunoblot analyses confirmed that these subunits are …
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
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. …