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282 results on '"Lonergan, Pat"'

14. Machine-learning methods applied to integrated transcriptomic data from bovine blastocysts and elongating conceptuses to identify genes predictive of embryonic competence

Author

Rabaglino, Maria Belen, Salilew-Wondim, Dessie, Zolini, Adriana, Tesfaye, Dawit, Hoelker, Michael, Lonergan, Pat, Hansen, Peter J, Rabaglino, Maria Belen, Salilew-Wondim, Dessie, Zolini, Adriana, Tesfaye, Dawit, Hoelker, Michael, Lonergan, Pat, and Hansen, Peter J

Abstract

Early pregnancy loss markedly impacts reproductive efficiency in cattle. The objectives were to model a biologically relevant gene signature predicting embryonic competence for survival after integrating transcriptomic data from blastocysts and elongating conceptuses with different developmental capacities and to validate the potential biomarkers with independent embryonic data sets through the application of machine-learning algorithms. First, two data sets from in vivo-produced blastocysts competent or not to sustain a pregnancy were integrated with a data set from long and short day-15 conceptuses. A statistical contrast determined differentially expressed genes (DEG) increasing in expression from a competent blastocyst to a long conceptus and vice versa; these were enriched for KEGG pathways related to glycolysis/gluconeogenesis and RNA processing, respectively. Next, the most discriminative DEG between blastocysts that resulted or did not in pregnancy were selected by linear discriminant analysis. These eight putative biomarker genes were validated by modeling their expression in competent or noncompetent blastocysts through Bayesian logistic regression or neural networks and predicting embryo developmental fate in four external data sets consisting of in vitro-produced blastocysts (i) competent or not, or (ii) exposed or not to detrimental conditions during culture, and elongated conceptuses (iii) of different length, or (iv) developed in the uteri of high- or subfertile heifers. Predictions for each data set were more than 85% accurate, suggesting that these genes play a key role in embryo development and pregnancy establishment. In conclusion, this study integrated transcriptomic data from seven independent experiments to identify a small set of genes capable of predicting embryonic competence for survival.

Published
2023

16. Machine-learning methods applied to integrated transcriptomic data from bovine blastocysts and elongating conceptuses to identify genes predictive of embryonic competence

Author

FAH GZ herkauwer, FAH – Sustainable Ruminant Health, Rabaglino, Maria Belen, Salilew-Wondim, Dessie, Zolini, Adriana, Tesfaye, Dawit, Hoelker, Michael, Lonergan, Pat, Hansen, Peter J, FAH GZ herkauwer, FAH – Sustainable Ruminant Health, Rabaglino, Maria Belen, Salilew-Wondim, Dessie, Zolini, Adriana, Tesfaye, Dawit, Hoelker, Michael, Lonergan, Pat, and Hansen, Peter J

Published
2023

17. The oocyte: the key player in the success of assisted reproduction technologies.

Author

Fair, Trudee and Lonergan, Pat

Subjects
*OVUM, *REPRODUCTIVE technology, *OVARIAN follicle, *PHYSIOLOGY, *EMBRYO transfer, *CATTLE fertility, *NANOTECHNOLOGY
Abstract

The ovulation of a mature oocyte at metaphase II of meiosis, with optimal potential to undergo fertilisation by a sperm cell, complete meiosis and sustain the switch to mitotic division, and support early embryo development, involves a protracted and disrupted/delayed series of processes. Many of these are targeted for exploitation in vivo , or recapitulation in vitro , by the livestock industry. Reproductive technologies, including AI, multiple ovulation embryo transfer, ovum pick-up, in vitro embryo production, and oestrus and ovulation synchronisation, offer practitioners and producers the opportunity to produce offspring from genetically valuable dams in much greater numbers than they would normally have in their lifetime, while in vitro oocyte and follicle culture are important platforms for researchers to interrogate the physiological mechanisms driving fertility. The majority of these technologies target the ovarian follicle and the oocyte within; thus, the quality and capability of the recovered oocyte determine the success of the reproductive intervention. Molecular and microscopical technologies have grown exponentially, providing powerful platforms to interrogate the molecular mechanisms which are integral to or affected by ART. The development of the bovine oocyte from its differentiation in the ovary to ovulation is described in the light of its relevance to key aspects of individual interventions, while highlighting the historical timeline. The development of the bovine oocyte from its differentiation in the ovary to ovulation is described from the perspective of each stage of oocyte and follicle development. The characteristic processes and pathways and the regulatory factors critical to each stage are detailed, along with their relevance to key aspects of individual assisted reproductive technologies. The historical timeline is also highlighted. Graphic designed by Trudee Fair, incorporating artwork by Iseult Lonergan. [ABSTRACT FROM AUTHOR]

Published
2024
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24. RNA-sequencing reveals genes linked with oocyte developmental potential in bovine cumulus cells

Author

Martínez-Moro, Álvaro, González-Brusi, Leopoldo, Lamas-Toranzo, Ismael, O'Callaghan, Elena, Esteve-Codina, Anna, Lonergan, Pat, and Bermejo-Álvarez, Pablo

Subjects
Integrins, Cumulus Cells, Granulosa cell, Embryonic Development, Integrin, Cell Biology, In Vitro Oocyte Maturation Techniques, Oxygen, Blastocyst, Oocyte quality, Oocytes, Genetics, In vitro maturation, Animals, RNA, Cattle, Female, Transcription, Developmental Biology
Abstract

Cumulus cells provide an interesting biological material to perform analyses to understand the molecular clues determining oocyte competence. The objective of this study was to analyze the transcriptional differences between cumulus cells from oocytes exhibiting different developmental potentials following individual in vitro embryo production by RNA-seq. Cumulus cells were allocated into three groups according to the developmental potential of the oocyte following fertilization: (1) oocytes developing to blastocysts (Bl+), (2) oocytes cleaving but arresting development before the blastocyst stage (Bl-), and (3) oocytes not cleaving (Cl-). RNAseq was performed on 4 (Cl-) or 5 samples (Bl+ and Bl-) of cumulus cells pooled from 10 cumulus-oocyte complexes per group. A total of 49, 50, and 18 differentially expressed genes (DEGs) were detected in the comparisons Bl+ versus Bl-, Bl+ versus Cl- and Bl- versus Cl-, respectively, showing a fold change greater than 1.5 at an adjusted p value

Published
2022

36. Mating to Intact, but Not Vasectomized, Males Elicits Changes in the Endometrial Transcriptome: Insights From the Bovine Model

Author

Recuero, Sandra, primary, Sánchez, José María, additional, Mateo-Otero, Yentel, additional, Bagés-Arnal, Sandra, additional, McDonald, Michael, additional, Behura, Susanta K., additional, Spencer, Thomas E., additional, Kenny, David A., additional, Yeste, Marc, additional, Lonergan, Pat, additional, and Fernandez-Fuertes, Beatriz, additional

Published
2020
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37. TMEM95 is a sperm membrane protein essential for mammalian fertilization

Author

Lamas-Toranzo, Ismael, primary, Hamze, Julieta G, additional, Bianchi, Enrica, additional, Fernández-Fuertes, Beatriz, additional, Pérez-Cerezales, Serafín, additional, Laguna-Barraza, Ricardo, additional, Fernández-González, Raúl, additional, Lonergan, Pat, additional, Gutiérrez-Adán, Alfonso, additional, Wright, Gavin J, additional, Jiménez-Movilla, María, additional, and Bermejo-Álvarez, Pablo, additional

Published
2020
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41. Author response: TMEM95 is a sperm membrane protein essential for mammalian fertilization

Author

Lamas-Toranzo, Ismael, primary, Hamze, Julieta G, additional, Bianchi, Enrica, additional, Fernández-Fuertes, Beatriz, additional, Pérez-Cerezales, Serafín, additional, Laguna-Barraza, Ricardo, additional, Fernández-González, Raúl, additional, Lonergan, Pat, additional, Gutiérrez-Adán, Alfonso, additional, Wright, Gavin J, additional, Jiménez-Movilla, María, additional, and Bermejo-Álvarez, Pablo, additional

Published
2020
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48. Functional significance of the signal transduction pathways Akt and Erk in ovarian follicles: in vitro and in vivo studies in cattle and sheep

Author

Ryan Kate E, Glister Claire, Lonergan Pat, Martin Finian, Knight Phil G, and Evans Alexander CO

Subjects
Gynecology and obstetrics, RG1-991
Abstract

Abstract Background The intracellular signalling mechanisms that regulate ovarian follicle development are unclear; however, we have recently shown differences in the Akt and Erk signalling pathways in dominant compared to subordinate follicles. The aim of this study was to investigate the effects of inhibiting Akt and Erk phosphorylation on IGF- and gonadotropin- stimulated granulosa and theca cell function in vitro, and on follicle development in vivo. Methods Bovine granulosa and theca cells were cultured for six days and stimulated with FSH and/or IGF, or LH in combination with PD98059 (Erk inhibitor) and/or LY294002 (Akt inhibitor) and their effect on cell number and hormone secretion (estradiol, activin-A, inhibin-A, follistatin, progesterone and androstenedione) determined. In addition, ovarian follicles were treated in vivo with PD98059 and/or LY294002 in ewes on Day 3 of the cycle and follicles were recovered 48 hours later. Results We have shown that gonadotropin- and IGF-stimulated hormone production by granulosa and theca cells is reduced by treatment with PD98059 and LY294002 in vitro. Furthermore, treatment with PD98059 and LY294002 reduced follicle growth and oestradiol production in vivo. Conclusion These results demonstrate an important functional role for the Akt and Erk signalling pathways in follicle function, growth and development.

Published
2008
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49. Maternal metabolism affects endometrial expression of oxidative stress and FOXL2 genes in cattle

Author

Lesage-Padilla, Audrey, Forde, Niamh, Poirée, Mélanie, Healey, Gareth D, Giraud-Delville, Corinne, Reinaud, Pierrette, Eozenou, Caroline, Vitorino Carvalho, Anais, Galio, Laurent, Raliou, Mariam, Oudin, Jean-François, Richard, Christophe, Sheldon, I Martin, Charpigny, Gilles, Lonergan, Pat, Sandra, Olivier, Biologie du Développement et Reproduction (BDR), École nationale vétérinaire d'Alfort (ENVA)-Institut National de la Recherche Agronomique (INRA), Université Paris Saclay (COmUE), School of Agriculture and Food Science, University College Dublin [Dublin] (UCD), Institute of Life Science [Swansea], Swansea University, European Union Seventh Framework Programme FP7/2007-2013, agreement N° 312097 (Fecund) et UK Biotechnology and Biological Sciences Research Council (BBSRC, and BB/1017240/1)

Subjects
Forkhead Box Protein L2, Physiology, lcsh:Medicine, Gene Expression, Pregnancy Proteins, Biochemistry, Endometrium, Endocrinology, Animal Cells, Reproductive Physiology, Medicine and Health Sciences, lcsh:Science, Enzyme Chemistry, [SDV.BDD]Life Sciences [q-bio]/Development Biology, Connective Tissue Cells, Mammals, Principal Component Analysis, food and beverages, Eukaryota, Ruminants, Catalase, Connective Tissue, Interferon Type I, Vertebrates, Female, Anatomy, Cellular Types, Research Article, Real-Time Polymerase Chain Reaction, Enzyme Regulation, Bovines, Genetics, Animals, Lactation, Gene Regulation, RNA, Messenger, Endocrine Physiology, Superoxide Dismutase, lcsh:R, Uterus, Reproductive System, Organisms, Biology and Life Sciences, [SDV.BDLR]Life Sciences [q-bio]/Reproductive Biology, Cell Biology, Fibroblasts, Oxidative Stress, Biological Tissue, Amniotes, Enzymology, lcsh:Q, Cattle
Abstract

Remerciements à Isabelle Hue (INRA, Jouy-en-Josas) et à l'Unité Commune d’Expérimentation Animale (UCEA, INRA, Leudeville) for animal management. Remerciements à Eric Pailhoux et Maëlle Pannetier (INRA, Jouy-en-Josas) for providing us FOXL2-pSG5 and pSG5 plasmids. Remerciements à Kaïs Al-Gubory et Philippe Bolifraud (INRA, Jouy-en-Josas) Remerciements à ICE platform (Claudia Bevilacqua and Nicolas Crapart, INRA, Jouy-en-Josas) for access to the bioanalyzer; International audience; Intensive selection for milk production has led to reduced reproductive efficiency in high-producing dairy cattle. The impact of intensive milk production on oocyte quality as well as early embryo development has been established but few analyses have addressed this question at the initiation of implantation, a critical milestone ensuring a successful pregnancy and normal post-natal development. Our study aimed to determine if contrasted maternal metabolism affects the previously described sensory properties of the endometrium to the conceptus in cattle. Following embryo transfer at Day 7 post-oestrus, endometrial caruncular (CAR) and intercaruncular (ICAR) areas were collected at Day 19 from primiparous postpartum Holstein-Friesian cows that were dried-off immediately after parturition (i.e., never milked; DRY) or milked twice daily (LACT). Gene quantification indicated no significant impact of lactation on endometrial expression of transcripts previously reported as conceptus-regulated (PLET1, PTGS2, SOCS6) and interferon-tau stimulated (RSAD2, SOCS1, SOCS3, STAT1) factors or known as female hormone-regulated genes (FOXL2, SCARA5, PTGS2). Compared with LACT cows, DRY cows exhibited mRNA levels with increased expression for FOXL2 transcription factor and decreased expression for oxidative stress-related genes (CAT, SOD1, SOD2). In vivo and in vitro experiments highlighted that neither interferon-tau nor FOXL2 were involved in transcriptional regulation of CAT, SOD1 and SOD2. In addition, our data showed that variations in maternal metabolism had a higher impact on gene expression in ICAR areas. Collectively, our findings prompt the need to fully understand the extent to which modifications in endometrial physiology drive the trajectory of conceptus development from implantation onwards when maternal metabolism is altered.

Published
2017
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