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Wilson AB, Whittington CM, Meyer A, Scobell SK, Gauthier ME. Prolactin and the evolution of male pregnancy. Gen Comp Endocrinol 2023; 334:114210. [PMID: 36646326 DOI: 10.1016/j.ygcen.2023.114210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 11/04/2022] [Accepted: 01/11/2023] [Indexed: 01/15/2023]
Abstract
Prolactin (PRL) is a multifunctional hormone of broad physiological importance, and is involved in many aspects of fish reproduction, including the regulation of live birth (viviparity) and both male and female parental care. Previous research suggests that PRL also plays an important reproductive role in syngnathid fishes (seahorses, pipefish and seadragons), a group with a highly derived reproductive strategy, male pregnancy - how the PRL axis has come to be co-opted for male pregnancy remains unclear. We investigated the molecular evolution and expression of the genes for prolactin and its receptor (PRLR) in an evolutionarily diverse sampling of syngnathid fishes to explore how the co-option of PRL for male pregnancy has impacted its evolution, and to clarify whether the PRL axis is also involved in regulating reproductive function in species with more rudimentary forms of male pregnancy. In contrast to the majority of teleost fishes, all syngnathid fishes tested carry single copies of PRL and PRLR that cluster genetically within the PRL1 and PRLRa lineages of teleosts, respectively. PRL1 gene expression in seahorses and pipefish is restricted to the pituitary, while PRLRa is expressed in all tissues, including the brood pouch of species with both rudimentary and complex brooding structures. Pituitary PRL1 expression remains stable throughout pregnancy, but PRLRa expression is specifically upregulated in the male brood pouch during pregnancy, consistent with the higher affinity of pouch tissues for PRL hormone during embryonic incubation. Finally, immunohistochemistry of brood pouch tissues reveals that both PRL1 protein and PRLRa and Na+/K+ ATPase-positive cells line the inner pouch epithelium, suggesting that pituitary-derived PRL1 may be involved in brood pouch osmoregulation during pregnancy. Our data provide a unique molecular perspective on the evolution and expression of prolactin and its receptor during male pregnancy, and provide the foundation for further manipulative experiments exploring the role of PRL in this unique form of reproduction.
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Affiliation(s)
- Anthony B Wilson
- Department of Biology, Brooklyn College, 2900 Bedford Avenue, Brooklyn, NY 11210, United States; The Graduate Center, City University of New York, 365 Fifth Avenue, New York, NY 10016, United States; Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich 8057, Switzerland; Department of Biology, University of Konstanz, Universitätsstrasse 10, 78457, Germany.
| | - Camilla M Whittington
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich 8057, Switzerland; Sydney School of Veterinary Science, University of Sydney, Sydney 2006, Australia; School of Life and Environmental Sciences, University of Sydney, Sydney 2006, Australia
| | - Axel Meyer
- Department of Biology, University of Konstanz, Universitätsstrasse 10, 78457, Germany
| | - Sunny K Scobell
- Department of Biology, Brooklyn College, 2900 Bedford Avenue, Brooklyn, NY 11210, United States
| | - Marie-Emilie Gauthier
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich 8057, Switzerland
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Stenhouse C, Seo H, Wu G, Johnson GA, Bazer FW. Insights into the Regulation of Implantation and Placentation in Humans, Rodents, Sheep, and Pigs. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1354:25-48. [PMID: 34807435 DOI: 10.1007/978-3-030-85686-1_2] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Precise cell-specific spatio-temporal molecular signaling cascades regulate the establishment and maintenance of pregnancy. Importantly, the mechanisms regulating uterine receptivity, conceptus apposition and adhesion to the uterine luminal epithelia/superficial glandular epithelia and, in some species, invasion into the endometrial stroma and decidualization of stromal cells, are critical prerequisite events for placentation which is essential for the appropriate regulation of feto-placental growth for the remainder of pregnancy. Dysregulation of these signaling cascades during this critical stage of pregnancy can lead to pregnancy loss, impaired growth and development of the conceptus, and alterations in the transplacental exchange of gasses and nutrients. While many of these processes are conserved across species, significant variations in the molecular mechanisms governing maternal recognition of pregnancy, conceptus implantation, and placentation exist. This review addresses the complexity of key mechanisms that are critical for the establishment and maintenance of a successful pregnancy in humans, rodents, sheep, and pigs. Improving understanding of the molecular mechanisms governing these processes is critical to enhancing the fertility and reproductive health of humans and livestock species.
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Affiliation(s)
- Claire Stenhouse
- Department of Animal Science and Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, 77843, USA
| | - Heewon Seo
- Department of Animal Science and Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, 77843, USA
| | - Guoyao Wu
- Department of Animal Science and Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, 77843, USA
| | - Gregory A Johnson
- Department of Animal Science and Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, 77843, USA
| | - Fuller W Bazer
- Department of Animal Science and Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, 77843, USA.
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Robertson CE, Wilsterman K. Developmental and reproductive physiology of small mammals at high altitude: challenges and evolutionary innovations. ACTA ACUST UNITED AC 2020; 223:223/24/jeb215350. [PMID: 33443053 DOI: 10.1242/jeb.215350] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
High-altitude environments, characterized by low oxygen levels and low ambient temperatures, have been repeatedly colonized by small altricial mammals. These species inhabit mountainous regions year-round, enduring chronic cold and hypoxia. The adaptations that allow small mammals to thrive at altitude have been well studied in non-reproducing adults; however, our knowledge of adaptations specific to earlier life stages and reproductive females is extremely limited. In lowland natives, chronic hypoxia during gestation affects maternal physiology and placental function, ultimately limiting fetal growth. During post-natal development, hypoxia and cold further limit growth both directly by acting on neonatal physiology and indirectly via impacts on maternal milk production and care. Although lowland natives can survive brief sojourns to even extreme high altitude as adults, reproductive success in these environments is very low, and lowland young rarely survive to sexual maturity in chronic cold and hypoxia. Here, we review the limits to maternal and offspring physiology - both pre-natal and post-natal - that highland-adapted species have overcome, with a focus on recent studies on high-altitude populations of the North American deer mouse (Peromyscus maniculatus). We conclude that a combination of maternal and developmental adaptations were likely to have been critical steps in the evolutionary history of high-altitude native mammals.
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Affiliation(s)
| | - Kathryn Wilsterman
- Division of Biological Sciences, University of Montana, Missoula, MT 59802, USA
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Roberts GAG, Tunster SJ. Characterising the dynamics of placental glycogen stores in the mouse. Placenta 2020; 99:131-140. [PMID: 32798765 DOI: 10.1016/j.placenta.2020.07.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 06/26/2020] [Accepted: 07/13/2020] [Indexed: 10/23/2022]
Abstract
INTRODUCTION The placenta performs a range of functions to support fetal growth. In addition to facilitating nutrient transport, the placenta also stores glucose as glycogen, which is thought to maintain fetal glucose supply during late gestation. However, evidence to support such a role is currently lacking. Similarly, our understanding of the dynamics of placental glycogen metabolism in normal mouse pregnancy is limited. METHODS We quantified the placental glycogen content of wild type C57BL/6JOlaHsd mouse placentas from mid (E12.5) to late (E18.5) gestation, alongside characterising the temporal expression pattern of genes encoding glycogenesis and glycogenolysis pathway enzymes. To assess the potential of the placenta to produce glucose, we investigated the spatiotemporal expression of glucose 6-phosphatase by qPCR and in situ hybridisation. Separate analyses were undertaken for placentas of male and female conceptuses to account for potential sexual dimorphism. RESULTS Placental glycogen stores peak at E15.5, having increased over 5-fold from E12.5, before declining by a similar extent by E18.5. Glycogen stores were 17% higher in male placentas than in females at E15.5. Expression of glycogen branching enzyme (Gbe1) was reduced ~40% towards term. Expression of the glucose 6-phosphatase isoform G6pc3 was enriched in glycogen trophoblast cells and increased towards term. DISCUSSION Reduced expression of Gbe1 suggests a decline in glycogen branching towards term. Expression of G6pc3 by glycogen trophoblasts is consistent with an ability to produce and release glucose from glycogen stores. However, the ultimate destination of the glucose generated from placental glycogen remains to be elucidated.
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Affiliation(s)
- George A G Roberts
- Centre for Trophoblast Research, Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, CB2 3EG, UK
| | - Simon J Tunster
- Centre for Trophoblast Research, Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, CB2 3EG, UK.
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Soares MJ, Iqbal K, Kozai K. Hypoxia and Placental Development. Birth Defects Res 2018; 109:1309-1329. [PMID: 29105383 DOI: 10.1002/bdr2.1135] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 09/04/2017] [Indexed: 12/17/2022]
Abstract
Hemochorial placentation is orchestrated through highly regulated temporal and spatial decisions governing the fate of trophoblast stem/progenitor cells. Trophoblast cell acquisition of specializations facilitating invasion and uterine spiral artery remodeling is a labile process, sensitive to the environment, and represents a process that is vulnerable to dysmorphogenesis in pathologic states. Hypoxia is a signal guiding placental development, and molecular mechanisms directing cellular adaptations to low oxygen tension are integral to trophoblast cell differentiation and placentation. Hypoxia can also be used as an experimental tool to investigate regulatory processes controlling hemochorial placentation. These developmental processes are conserved in mouse, rat, and human placentation. Consequently, elements of these developmental events can be modeled and hypotheses tested in trophoblast stem cells and in genetically manipulated rodents. Hypoxia is also a consequence of a failed placenta, yielding pathologies that can adversely affect maternal adjustments to pregnancy, fetal health, and susceptibility to adult disease. The capacity of the placenta for adaptation to environmental challenges highlights the importance of its plasticity in safeguarding a healthy pregnancy. Birth Defects Research 109:1309-1329, 2017.© 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Michael J Soares
- Institute for Reproduction and Perinatal Research, Department of Pathology and Laboratory Medicine, University of Kansas Medical Center, Kansas City, Kansas.,Department of Pediatrics, University of Kansas Medical Center, Kansas City, Kansas.,Fetal Health Research, Children's Research Institute, Children's Mercy, Kansas City, Missouri
| | - Khursheed Iqbal
- Institute for Reproduction and Perinatal Research, Department of Pathology and Laboratory Medicine, University of Kansas Medical Center, Kansas City, Kansas
| | - Keisuke Kozai
- Institute for Reproduction and Perinatal Research, Department of Pathology and Laboratory Medicine, University of Kansas Medical Center, Kansas City, Kansas
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Whittington CM, Wilson AB. The role of prolactin in fish reproduction. Gen Comp Endocrinol 2013; 191:123-36. [PMID: 23791758 DOI: 10.1016/j.ygcen.2013.05.027] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Revised: 05/14/2013] [Accepted: 05/31/2013] [Indexed: 11/16/2022]
Abstract
Prolactin (PRL) has one of the broadest ranges of functions of any vertebrate hormone, and plays a critical role in regulating aspects of reproduction in widely divergent lineages. However, while PRL structure, mode of action and functions have been well-characterised in mammals, studies of other vertebrate lineages remain incomplete. As the most diverse group of vertebrates, fish offer a particularly valuable model system for the study of the evolution of reproductive endocrine function. Here, we review the current state of knowledge on the role of prolactin in fish reproduction, which extends to migration, reproductive development and cycling, brood care behaviour, pregnancy, and nutrient provisioning to young. We also highlight significant gaps in knowledge and advocate a specific bidirectional research methodology including both observational and manipulative experiments. Focusing research efforts towards the thorough characterisation of a restricted number of reproductively diverse fish models will help to provide the foundation necessary for a more explicitly evolutionary analysis of PRL function.
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Affiliation(s)
- Camilla M Whittington
- Institute of Evolutionary Biology and Environmental Science, University of Zurich, Winterthurerstrasse 190, Zurich 8057, Switzerland.
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Placentation in the African elephant (Loxodonta africana). V. The trophoblast secretes placental lactogen. Placenta 2011; 32:506-10. [DOI: 10.1016/j.placenta.2011.04.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Revised: 04/13/2011] [Accepted: 04/15/2011] [Indexed: 11/19/2022]
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Simmons DG, Rawn S, Davies A, Hughes M, Cross JC. Spatial and temporal expression of the 23 murine Prolactin/Placental Lactogen-related genes is not associated with their position in the locus. BMC Genomics 2008; 9:352. [PMID: 18662396 PMCID: PMC2527339 DOI: 10.1186/1471-2164-9-352] [Citation(s) in RCA: 176] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2008] [Accepted: 07/28/2008] [Indexed: 02/06/2023] Open
Abstract
Background The Prolactin (PRL) hormone gene family shows considerable variation among placental mammals. Whereas there is a single PRL gene in humans that is expressed by the pituitary, there are an additional 22 genes in mice including the placental lactogens (PL) and Prolactin-related proteins (PLPs) whose expression is limited to the placenta. To understand the regulation and potential functions of these genes, we conducted a detailed temporal and spatial expression study in the placenta between embryonic days 7.5 and E18.5 in three genetic strains. Results Of the 22 PRL/PL genes examined, only minor differences were observed among strains of mice. We found that not one family member has the same expression pattern as another when both temporal and spatial data were examined. There was also no correlation in expression between genes that were most closely related or between adjacent genes in the PRL/PL locus. Bioinformatic analysis of upstream regulatory regions identified conserved combinations (modules) of putative transcription factor binding sites shared by genes expressed in the same trophoblast subtype, supporting the notion that local regulatory elements, rather than locus control regions, specify subtype-specific expression. Further diversification in expression was also detected as splice variants for several genes. Conclusion In the present study, a detailed temporal and spatial placental expression map was generated for all murine PRL/PL family members from E7.5 to E18.5 of gestation in three genetic strains. This detailed analysis uncovered several new markers for some trophoblast cell types that will be useful for future analysis of placental structure in mutant mice with placental phenotypes. More importantly, several main conclusions about regulation of the locus are apparent. First, no two family members have the same expression pattern when both temporal and spatial data are examined. Second, most genes are expressed in multiple trophoblast cell subtypes though none were detected in the chorion, where trophoblast stem cells reside, or in syncytiotrophoblast of the labyrinth layer. Third, bioinformatic comparisons of upstream regulatory regions identified predicted transcription factor binding site modules that are shared by genes expressed in the same trophoblast subtype. Fourth, further diversification of gene products from the PRL/PL locus occurs through alternative splice isoforms for several genes.
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Affiliation(s)
- David G Simmons
- Department of Comparative Biology & Experimental Medicine, The University of Calgary, Calgary, Canada.
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Gene expression profiles of novel caprine placental prolactin-related proteins similar to bovine placental prolactin-related proteins. BMC DEVELOPMENTAL BIOLOGY 2007; 7:16. [PMID: 17359547 PMCID: PMC1847437 DOI: 10.1186/1471-213x-7-16] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/26/2006] [Accepted: 03/15/2007] [Indexed: 11/25/2022]
Abstract
Background This study reports the identification of a full-length cDNA sequence for two novel caprine prolactin-related proteins (cPRP1 and cPRP6), and their localization and quantitative expression in the placenta. Caprine PRPs are compared with known bovine PRPs. We examined their evolution and role in the ruminant placenta. Results Full-length cPRP1 and cPRP6 cDNA were cloned with a 717- and 720- nucleotide open-reading frame corresponding to proteins of 238 and 239 amino acids. The cPRP1 predicted amino acid sequence shares a 72% homology with bovine PRP1 (bPRP1). The cPRP6 predicted amino acid sequence shares a 74% homology with bovine PRP6 (bPRP6). The two cPRPs as well as bPRPs were detected only in the placentome by RT-PCR. Analysis by in situ hybridization revealed the presence of both cPRPs mRNA in the trophoblast binucleate cells. These mRNA were quantified by real-time RT-PCR analysis of the placentome at 30, 50, 90 and 140 days of pregnancy. Both new cPRP genes were able to translate a mature protein in a mammalian cell-expression system. Western blotting established the molecular sizes of 33 kDa for cPRP1 with FLAG-tag and 45 kDa for cPRP6 with FLAG-tag. The sequence properties and localized expression of cPRP1 and cPRP6 were similar to those of bovine. However, their expression profiles differed from those in bovine placenta. Although this study demonstrated possible roles of PRPs in caprine placenta, PRPs may regulate binucleate-cell functions like those in bovine, but their crucial roles are still unclear. Conclusion We have identified the novel PRPs in caprine placenta. Localization and quantitative expression of caprine PRPs were compared with bovine PRPs. The data indicate that PRP genes in caprine placenta have coordination functions for gestation, as they do in bovine. This is the first study of PRPs function in caprine placenta.
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Ho-Chen JK, Bustamante JJ, Soares MJ. Prolactin-like protein-f subfamily of placental hormones/cytokines: responsiveness to maternal hypoxia. Endocrinology 2007; 148:559-65. [PMID: 17095594 DOI: 10.1210/en.2006-1146] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The prolactin (PRL) family of hormones/cytokines is involved in the maintenance of pregnancy and adaptations to physiological stressors. In this report, we identify and characterize a new member of the rat PRL family, examine the impact of maternal hypoxia on placental PRL family gene expression, and investigate maternal adaptive responses to hypoxia. Perusal of the PRL gene family locus in the rat genome resulted in the identification of a putative new member of the rat PRL family. The new member is closely related to the previously reported PRL-like protein-F (PLP-F) and has been named PLP-Fbeta and the originally characterized PLP-F, now termed PLP-Falpha. The two proteins exhibit structural similarities but possess distinct cell- and temporal-specific expression profiles. In vivo hypoxia stimulates placental PLP-Falpha and PLP-E mRNA expression in the rat and mouse, respectively. Rcho-1 trophoblast cells can differentiate into trophoblast giant cells, express PLP-Falpha, and exhibit enhanced PLP-Falpha mRNA levels when cultured under low oxygen tension (2%). Exposure to hypobaric hypoxia during latter part of pregnancy did not significantly impact the expression of PLP-Fbeta mRNA. Finally, exposure to hypobaric hypoxia during midpregnancy led to increased maternal red blood cells, hemoglobin concentrations, hematocrit, and increased concentrations of maternal splenic mRNAs for key proteins involved in hemoglobin synthesis, erythroid Krüppel-like factor, erythroid 5-aminolevulinate synthase-2, and beta-major globin. In summary, adaptive responses to maternal hypoxia include activation of placental PLP-Falpha/E gene expression, which may then participate in maternal hematological adjustments required for maintaining maternal and fetal oxygen delivery.
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Affiliation(s)
- Jennifer K Ho-Chen
- Institute of Maternal-Fetal Biology, Division of Cancer and Developmental Biology, Department of Pathology and Laboratory Medicine, University of Kansas Medical Center, Kansas City, Kansas 66160, USA
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Hashizume K, Ushizawa K, Patel OV, Kizaki K, Imai K, Yamada O, Nakano H, Takahashi T. Gene expression and maintenance of pregnancy in bovine: roles of trophoblastic binucleate cell-specific molecules. Reprod Fertil Dev 2007; 19:79-90. [PMID: 17389137 DOI: 10.1071/rd06118] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Cell to cell interaction plays a pivotal role in the regulation of placentogenesis and exchange of stage-specific developmental signals between the fetal and maternal units. Specifically, these interactions are paramount for programmed fetal growth, maternal adaptation to pregnancy and coordination of parturition. However, little is known about the precise regulation of placentation and maintenance of gestation in cattle. Therefore, the aim of the present study was to decipher the complex networks of cell communication to gain an insight into the multifaceted developmental process and understand the profound consequences of flawed communication. In the ruminant, the binucleate cell plays a central role in forming the structures and secretions at the fetomaternal interface that are crucial in establishing and maintaining pregnancy. Herein, we summarise differences in the abundance of specific RNA transcripts in the bovine cotyledon and caruncle using global gene expression profiling and further investigate the relationship of mRNA abundance for selected pregnancy-specific genes of interest (identified from microarray studies) that are localised exclusively to the binucleate cell, such as placental lactogen, prolactin-related proteins and pregnancy-associated glycoproteins. The results suggest that a well-orchestrated transcriptional command from binucleate cells is pivotal to the establishment and progression of pregnancy in cattle.
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Affiliation(s)
- Kazuyoshi Hashizume
- Department of Veterinary Medicine, Iwate University, Ueda 3-18-8, Morioka, Iwate 020-8550, Japan.
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Abstract
Pregnancy has been traditionally defined as the period during which developing embryos are incubated in the body after egg-sperm union. Despite strong similarities between viviparity in mammals and other vertebrate groups, researchers have historically been reluctant to use the term pregnancy for non-mammals in recognition of the highly developed form of viviparity in eutherians. Syngnathid fishes (seahorses and pipefishes) have a unique reproductive system, where the male incubates developing embryos in a specialized brooding structure in which they are aerated, osmoregulated, protected and likely provisioned during their development. Recent insights into physiological, morphological and genetic changes associated with syngnathid reproduction provide compelling evidence that male incubation in these species is a highly specialized form of reproduction akin to other forms of viviparity. Here, we review these recent advances, highlighting similarities and differences between seahorse and mammalian pregnancy. Understanding the changes associated with the parallel evolution of male pregnancy in the two major syngnathid lineages will help to identify key innovations that facilitated the development of this unique form of reproduction and, through comparison with other forms of live bearing, may allow the identification of a common set of characteristics shared by all viviparous organisms.
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TAKAHASHI T. Biology of the prolactin family in bovine placenta. I. Bovine placental lactogen: Expression, structure and proposed roles. Anim Sci J 2006. [DOI: 10.1111/j.1740-0929.2006.00314.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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USHIZAWA K, HASHIZUME K. Biology of the prolactin family in bovine placenta. II. Bovine prolactin-related proteins: Their expression, structure and proposed roles. Anim Sci J 2006. [DOI: 10.1111/j.1740-0929.2006.00315.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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