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Full-Text Articles in Medicine and Health Sciences

Association Of Pediatric Buccal Epigenetic Age Acceleration With Adverse Neonatal Brain Growth And Neurodevelopmental Outcomes Among Children Born Very Preterm With A Neonatal Infection., Noha Gomaa, Chaini Konwar, Nicole Gladish, Stephanie H Au-Young, Ting Guo, Min Sheng, Sarah M Merrill, Edmond Kelly, Vann Chau, Helen M Branson, Linh G Ly, Emma G Duerden, Ruth E Grunau, Michael S Kobor, Steven P Miller Nov 2022

Association Of Pediatric Buccal Epigenetic Age Acceleration With Adverse Neonatal Brain Growth And Neurodevelopmental Outcomes Among Children Born Very Preterm With A Neonatal Infection., Noha Gomaa, Chaini Konwar, Nicole Gladish, Stephanie H Au-Young, Ting Guo, Min Sheng, Sarah M Merrill, Edmond Kelly, Vann Chau, Helen M Branson, Linh G Ly, Emma G Duerden, Ruth E Grunau, Michael S Kobor, Steven P Miller

Department of Medicine Publications

IMPORTANCE: Very preterm neonates (24-32 weeks' gestation) remain at a higher risk of morbidity and neurodevelopmental adversity throughout their lifespan. Because the extent of prematurity alone does not fully explain the risk of adverse neonatal brain growth or neurodevelopmental outcomes, there is a need for neonatal biomarkers to help estimate these risks in this population.

OBJECTIVES: To characterize the pediatric buccal epigenetic (PedBE) clock-a recently developed tool to measure biological aging-among very preterm neonates and to assess its association with the extent of prematurity, neonatal comorbidities, neonatal brain growth, and neurodevelopmental outcomes at 18 months of age.

DESIGN, SETTING, AND …


The 2021 Eurpean Alliance Of Associations For Rheumatology/American College Of Rheumatology Points To Consider For Diagnosis And Management Of Autoinflammatory Type I Interferonopathies: Candle/Praas, Savi And Ags, Kader Cetin Gedik, Lovro Lamot, Micol Romano, Erkan Demirkaya, David Piskin, Sofia Torreggiani, Laura A. Adang, Thais Armangue, Kathe Barchus, Devon R. Cordova, Yanick J. Crow, Russell C. Dale, Karen L. Durrant, Despina Eleftheriou, Elisa M. Fazzi, Marco Gattorno, Francesco Gavazzi, Eric P. Hanson, Min Ae Lee-Kirsch, Gina A. Montealegre Sanchez, Bénédicte Neven, Simona Orcesi, Seza Ozen, M. Cecilia Poli, Elliot Schumacher, Davide Tonduti, Katsiaryna Uss, Daniel Aletaha, Brian M. Feldman Jan 2022

The 2021 Eurpean Alliance Of Associations For Rheumatology/American College Of Rheumatology Points To Consider For Diagnosis And Management Of Autoinflammatory Type I Interferonopathies: Candle/Praas, Savi And Ags, Kader Cetin Gedik, Lovro Lamot, Micol Romano, Erkan Demirkaya, David Piskin, Sofia Torreggiani, Laura A. Adang, Thais Armangue, Kathe Barchus, Devon R. Cordova, Yanick J. Crow, Russell C. Dale, Karen L. Durrant, Despina Eleftheriou, Elisa M. Fazzi, Marco Gattorno, Francesco Gavazzi, Eric P. Hanson, Min Ae Lee-Kirsch, Gina A. Montealegre Sanchez, Bénédicte Neven, Simona Orcesi, Seza Ozen, M. Cecilia Poli, Elliot Schumacher, Davide Tonduti, Katsiaryna Uss, Daniel Aletaha, Brian M. Feldman

Paediatrics Publications

Objective: Autoinflammatory type I interferonopathies, chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature/proteasome-associated autoinflammatory syndrome (CANDLE/PRAAS), stimulator of interferon genes (STING)-associated vasculopathy with onset in infancy (SAVI) and Aicardi-Goutières syndrome (AGS) are rare and clinically complex immunodysregulatory diseases. With emerging knowledge of genetic causes and targeted treatments, a Task Force was charged with the development of 'points to consider' to improve diagnosis, treatment and long-term monitoring of patients with these rare diseases. Methods: Members of a Task Force consisting of rheumatologists, neurologists, an immunologist, geneticists, patient advocates and an allied healthcare professional formulated research questions for a systematic literature …


Investigating Gene-Environment Interaction In A Double-Hit Model For Autism Spectrum Disorder, Melvin Maroon Aug 2021

Investigating Gene-Environment Interaction In A Double-Hit Model For Autism Spectrum Disorder, Melvin Maroon

Undergraduate Student Research Internships Conference

With the exponential advancements seen in the field of sequencing technology, the science community has come to identify hundreds of potential genetic risk factors for neuropsychiatric disorders. Despite our knowledge that such risk factors exist, we have yet to understand their specific influences on the behavioral profile of an individual. In addition, maternal infection during pregnancy can have longstanding detrimental outcomes on a child’s development. This is especially impactful with the present threat of viral infection during the pandemic. Our study aims to understand the influence of a specific genetic and environmental factor on a preclinical rodent model’s behavioral development. …


New Horizons In The Genetic Etiology Of Systemic Lupus Erythematosus And Lupus-Like Disease: Monogenic Lupus And Beyond, Erkan Demirkaya, Sezgin Sahin, Micol Romano, Qing Zhou, Ivona Aksentijevich Mar 2020

New Horizons In The Genetic Etiology Of Systemic Lupus Erythematosus And Lupus-Like Disease: Monogenic Lupus And Beyond, Erkan Demirkaya, Sezgin Sahin, Micol Romano, Qing Zhou, Ivona Aksentijevich

Paediatrics Publications

Systemic lupus erythematosus (SLE) is a clinically and genetically heterogeneous autoimmune disease. The etiology of lupus and the contribution of genetic, environmental, infectious and hormonal factors to this phenotype have yet to be elucidated. The most straightforward approach to unravel the molecular pathogenesis of lupus may rely on studies of patients who present with early-onset severe phenotypes. Typically, they have at least one of the following clinical features: childhood onset of severe disease (<5 >years), parental consanguinity, and presence of family history for autoimmune diseases in a first-degree relative. These patients account for a small proportion of patients with lupus …


Blau Syndrome And Early-Onset Sarcoidosis: A Six Case Series And Review Of The Literature., Ayşenur Paç Kisaarslan, Betül Sözeri̇, Nihal Şahi̇n, Sümeyra Özdemi̇r Çi̇çek, Zübeyde Gündüz, Erkan Demi̇rkaya, Afig Berdeli̇, Serdal Sadet Özcan, Hakan Porazoğlu, Ruhan Düşünsel Mar 2020

Blau Syndrome And Early-Onset Sarcoidosis: A Six Case Series And Review Of The Literature., Ayşenur Paç Kisaarslan, Betül Sözeri̇, Nihal Şahi̇n, Sümeyra Özdemi̇r Çi̇çek, Zübeyde Gündüz, Erkan Demi̇rkaya, Afig Berdeli̇, Serdal Sadet Özcan, Hakan Porazoğlu, Ruhan Düşünsel

Paediatrics Publications

Objectives: This study aims to discuss the clinical, laboratory and genetic findings, and treatment options for six patients who were diagnosed with Blau syndrome (BS)/early-onset sarcoidosis (EOS).

Patients and methods: The study included four patients (2 males,2 females; mean age 7 years; range 4 to 10 years) with EOS and two siblings (1 male, 1 female; mean age 10 years; range, 9 to 11 years) with BS. Age, age of initial symptoms, age of diagnosis; articular involvement, presence of uveitis, dermatitis, or fever, other organ involvement, laboratory findings, results of metabolic tests for mucopolysaccharidosis and mucolipidosis, results of genetic, pathologic, …


What We Can Learn From A Genetic Rodent Model About Autism., Dorit Möhrle, Marta Fernández, Olga Peñagarikano, Andreas Frick, Brian Allman, Susanne Schmid Feb 2020

What We Can Learn From A Genetic Rodent Model About Autism., Dorit Möhrle, Marta Fernández, Olga Peñagarikano, Andreas Frick, Brian Allman, Susanne Schmid

Anatomy and Cell Biology Publications

Autism spectrum disorders (ASD) are complex neurodevelopmental disorders that are caused by genetic and/or environmental impacts, often probably by the interaction of both. They are characterised by deficits in social communication and interaction and by restricted and repetitive behaviours and interests from early childhood on, causing significant impairment. While it is clear that no animal model captures the full complexity of ASD in humans, genetic models are extremely useful for studying specific symptoms associated with ASD and the underlying cellular and molecular mechanisms. In this review we summarize the behavioral paradigms used in rodents to model ASD symptoms as they …


Bafopathies' Dna Methylation Epi-Signatures Demonstrate Diagnostic Utility And Functional Continuum Of Coffin-Siris And Nicolaides-Baraitser Syndromes., Erfan Aref-Eshghi, Eric G Bend, Rebecca L Hood, Laila C Schenkel, Deanna Alexis Carere, Rana Chakrabarti, Sandesh C S Nagamani, Sau Wai Cheung, Philippe M Campeau, Chitra Prasad, Victoria Mok Siu, Lauren Brady, Mark A Tarnopolsky, David J Callen, A Micheil Innes, Susan M White, Wendy S Meschino, Andrew Y Shuen, Guillaume Paré, Dennis E Bulman, Peter J Ainsworth, Hanxin Lin, David I Rodenhiser, Raoul C Hennekam, Kym M Boycott, Charles E Schwartz, Bekim Sadikovic Nov 2018

Bafopathies' Dna Methylation Epi-Signatures Demonstrate Diagnostic Utility And Functional Continuum Of Coffin-Siris And Nicolaides-Baraitser Syndromes., Erfan Aref-Eshghi, Eric G Bend, Rebecca L Hood, Laila C Schenkel, Deanna Alexis Carere, Rana Chakrabarti, Sandesh C S Nagamani, Sau Wai Cheung, Philippe M Campeau, Chitra Prasad, Victoria Mok Siu, Lauren Brady, Mark A Tarnopolsky, David J Callen, A Micheil Innes, Susan M White, Wendy S Meschino, Andrew Y Shuen, Guillaume Paré, Dennis E Bulman, Peter J Ainsworth, Hanxin Lin, David I Rodenhiser, Raoul C Hennekam, Kym M Boycott, Charles E Schwartz, Bekim Sadikovic

Paediatrics Publications

Coffin-Siris and Nicolaides-Baraitser syndromes (CSS and NCBRS) are Mendelian disorders caused by mutations in subunits of the BAF chromatin remodeling complex. We report overlapping peripheral blood DNA methylation epi-signatures in individuals with various subtypes of CSS (ARID1B, SMARCB1, and SMARCA4) and NCBRS (SMARCA2). We demonstrate that the degree of similarity in the epi-signatures of some CSS subtypes and NCBRS can be greater than that within CSS, indicating a link in the functional basis of the two syndromes. We show that chromosome 6q25 microdeletion syndrome, harboring ARID1B deletions, exhibits a similar CSS/NCBRS methylation profile. Specificity of this epi-signature was confirmed across …


Epigenetic Etiology Of Intellectual Disability., Shigeki Iwase, Nathalie G Bérubé, Zhaolan Zhou, Nael Nadif Kasri, Elena Battaglioli, Marilyn Scandaglia, Angel Barco Nov 2017

Epigenetic Etiology Of Intellectual Disability., Shigeki Iwase, Nathalie G Bérubé, Zhaolan Zhou, Nael Nadif Kasri, Elena Battaglioli, Marilyn Scandaglia, Angel Barco

Paediatrics Publications

Intellectual disability (ID) is a prevailing neurodevelopmental condition associated with impaired cognitive and adaptive behaviors. Many chromatin-modifying enzymes and other epigenetic regulators have been genetically associated with ID disorders (IDDs). Here we review how alterations in the function of histone modifiers, chromatin remodelers, and methyl-DNA binding proteins contribute to neurodevelopmental defects and altered brain plasticity. We also discuss how progress in human genetics has led to the generation of mouse models that unveil the molecular etiology of ID, and outline the direction in which this field is moving to identify therapeutic strategies for IDDs. Importantly, because the chromatin regulators linked …


Heterozygous De Novo Ubtf Gain-Of-Function Variant Is Associated With Neurodegeneration In Childhood., Simon Edvardson, Claudia M Nicolae, Pankaj B Agrawal, Cyril Mignot, Katelyn Payne, Asuri Narayan Prasad, Chitra Prasad, Laurie Sadler, Caroline Nava, Thomas E Mullen, Amber Begtrup, Berivan Baskin, Zöe Powis, Avraham Shaag, Boris Keren, George-Lucian Moldovan, Orly Elpeleg Aug 2017

Heterozygous De Novo Ubtf Gain-Of-Function Variant Is Associated With Neurodegeneration In Childhood., Simon Edvardson, Claudia M Nicolae, Pankaj B Agrawal, Cyril Mignot, Katelyn Payne, Asuri Narayan Prasad, Chitra Prasad, Laurie Sadler, Caroline Nava, Thomas E Mullen, Amber Begtrup, Berivan Baskin, Zöe Powis, Avraham Shaag, Boris Keren, George-Lucian Moldovan, Orly Elpeleg

Paediatrics Publications

Ribosomal RNA (rRNA) is transcribed from rDNA by RNA polymerase I (Pol I) to produce the 45S precursor of the 28S, 5.8S, and 18S rRNA components of the ribosome. Two transcription factors have been defined for Pol I in mammals, the selectivity factor SL1, and the upstream binding transcription factor (UBF), which interacts with the upstream control element to facilitate the assembly of the transcription initiation complex including SL1 and Pol I. In seven unrelated affected individuals, all suffering from developmental regression starting at 2.5-7 years, we identified a heterozygous variant, c.628G>A in UBTF, encoding p.Glu210Lys in UBF, which …


Identification Of Epigenetic Signature Associated With Alpha Thalassemia/Mental Retardation X-Linked Syndrome, Laila C Schenkel, Kristin D Kernohan, Arran Mcbride, Ditta Reina, Amanda Hodge, Peter J Ainsworth, David I Rodenhiser, Guillaume Pare, Nathalie G Bérubé, Cindy Skinner, Kym M Boycott, Charles Schwartz, Bekim Sadikovic Jan 2017

Identification Of Epigenetic Signature Associated With Alpha Thalassemia/Mental Retardation X-Linked Syndrome, Laila C Schenkel, Kristin D Kernohan, Arran Mcbride, Ditta Reina, Amanda Hodge, Peter J Ainsworth, David I Rodenhiser, Guillaume Pare, Nathalie G Bérubé, Cindy Skinner, Kym M Boycott, Charles Schwartz, Bekim Sadikovic

Paediatrics Publications

BACKGROUND: Alpha thalassemia/mental retardation X-linked syndrome (ATR-X) is caused by a mutation at the chromatin regulator gene

RESULTS: We performed genome-wide DNA methylation assessment of the peripheral blood samples from 18 patients with ATR-X and compared it to 210 controls. We demonstrated the evidence of a unique and highly specific DNA methylation "epi-signature" in the peripheral blood of ATRX patients, which was corroborated by targeted bisulfite sequencing experiments. Although genomically represented, differentially methylated regions showed evidence of preferential clustering in pericentromeric and telometric chromosomal regions, areas where ATRX has multiple functions related to maintenance of heterochromatin and genomic integrity.

CONCLUSION: …


The Serotonin Transporter Promoter Polymorphism Moderates The Continuity Of Behavioral Inhibition In Early Childhood., Victoria C Johnson, Katie R Kryski, Haroon I Sheikh, Heather J Smith, Shiva M Singh, Elizabeth P Hayden Nov 2016

The Serotonin Transporter Promoter Polymorphism Moderates The Continuity Of Behavioral Inhibition In Early Childhood., Victoria C Johnson, Katie R Kryski, Haroon I Sheikh, Heather J Smith, Shiva M Singh, Elizabeth P Hayden

Brain and Mind Institute Researchers' Publications

Persistently elevated behavioral inhibition (BI) in children is a marker of vulnerability to psychopathology. However, little research has considered the joint influences of caregiver and child factors that may moderate the continuity of BI in early childhood, particularly genetic variants that may serve as markers of biological plasticity, such as the serotonin transporter linked polymorphic region (5-HTTLPR). We explored this issue in 371 preschoolers and their caregivers, examining whether parent characteristics (i.e., overinvolvement or anxiety disorder) and child 5-HTTLPR influenced the continuity of BI between ages 3 and 5. Measures were observational ratings of child BI, observational and questionnaire measures …


Neurogenesis-Mediated Forgetting Minimizes Proactive Interference., Jonathan R Epp, Rudy Silva Mera, Stefan Köhler, Sheena A Josselyn, Paul W Frankland Feb 2016

Neurogenesis-Mediated Forgetting Minimizes Proactive Interference., Jonathan R Epp, Rudy Silva Mera, Stefan Köhler, Sheena A Josselyn, Paul W Frankland

Brain and Mind Institute Researchers' Publications

Established memories may interfere with the encoding of new memories, particularly when existing and new memories overlap in content. By manipulating levels of hippocampal neurogenesis, here we show that neurogenesis regulates this form of proactive interference. Increasing hippocampal neurogenesis weakens existing memories and, in doing so, facilitates the encoding of new, conflicting (but not non-conflicting) information in mice. Conversely, decreasing neurogenesis stabilizes existing memories, and impedes the encoding of new, conflicting information. These results suggest that reduced proactive interference is an adaptive benefit of neurogenesis-induced forgetting.


Olanzapine-Induced Methylation Alters Cadherin Gene Families And Associated Pathways Implicated In Psychosis, Melkaye G. Melka, Christina A Castellani, Nagalingam Rajakumar, Richard O'Reilly, Shiva M Singh Sep 2014

Olanzapine-Induced Methylation Alters Cadherin Gene Families And Associated Pathways Implicated In Psychosis, Melkaye G. Melka, Christina A Castellani, Nagalingam Rajakumar, Richard O'Reilly, Shiva M Singh

Biology Publications

BACKGROUND: The complex aetiology of most mental disorders involves gene-environment interactions that may operate using epigenetic mechanisms particularly DNA methylation. It may explain many of the features seen in mental disorders including transmission, expression and antipsychotic treatment responses. This report deals with the assessment of DNA methylation in response to an antipsychotic drug (olanzapine) on brain (cerebellum and hippocampus), and liver as a non-neural reference in a rat model. The study focuses on the Cadherin/protocadherins encoded by a multi-gene family that serve as adhesion molecules and are involved in cell-cell communication in the mammalian brain. A number of these molecules …


Preimplantation Embryo Programming: Transcription, Epigenetics, And Culture Environment., Veronique Duranthon, Andrew J Watson, Patrick Lonergan Feb 2008

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 …


Oocyte Cytoplasmic Maturation: A Key Mediator Of Oocyte And Embryo Developmental Competence., A J Watson Mar 2007

Oocyte Cytoplasmic Maturation: A Key Mediator Of Oocyte And Embryo Developmental Competence., A J Watson

Obstetrics & Gynaecology Publications

Efforts have intensified to successfully mature and inseminate oocytes in vitro and then culture ensuing embryos to transferable stages from a large number of mammalian species. Success varies, but generally even for the most successful species it is only possible to obtain a maximum of a 40 to 50% development of zygotes to the blastocyst stage. Reduced oocyte developmental competence is suggested as a primary reason for the reduced potential of in vitro-produced embryos. The vast majority of in vitro-matured oocytes are meiotically competent; however, many do not attain an optimal oocyte diameter before insemination. Variations in oocyte in vitro …


Catm Regulation Of The Benabcde Operon: Functional Divergence Of Two Lysr-Type Paralogs In Acinetobacter Baylyi Adp1., Obidimma Ezezika, Lauren S Collier-Hyams, Haley A Dale, Andrew C Burk, Ellen L Neidle Mar 2006

Catm Regulation Of The Benabcde Operon: Functional Divergence Of Two Lysr-Type Paralogs In Acinetobacter Baylyi Adp1., Obidimma Ezezika, Lauren S Collier-Hyams, Haley A Dale, Andrew C Burk, Ellen L Neidle

Health Studies Publications

Two LysR-type transcriptional regulators, BenM and CatM, control benzoate consumption by the soil bacterium Acinetobacter baylyi ADP1. These homologs play overlapping roles in the expression of multiple genes. This study focuses on the benABCDE operon, which initiates benzoate catabolism. At this locus, BenM and CatM each activate transcription in response to the catabolite cis,cis-muconate. BenM, but not CatM, additionally responds to benzoate as an effector. Regulation by CatM alone is insufficient for growth on benzoate as the sole carbon source. However, three point mutations independently increased CatM-activated benA transcription and enabled growth on benzoate without BenM. Two mutations generate variants …


Effect Of Serum And Cumulus Cell Expansion On Marker Gene Transcripts In Bovine Cumulus-Oocyte Complexes During Maturation In Vitro., Michele D Calder, Anita N Caveney, Marc-Andre Sirard, Andrew J Watson Apr 2005

Effect Of Serum And Cumulus Cell Expansion On Marker Gene Transcripts In Bovine Cumulus-Oocyte Complexes During Maturation In Vitro., Michele D Calder, Anita N Caveney, Marc-Andre Sirard, Andrew J Watson

Obstetrics & Gynaecology Publications

OBJECTIVE: To determine the distribution of transcripts encoding the FSH receptor (FSHr), LH receptor (LHr), connexin 43 (Cx43), cyclooxygenase-2 (COX-2), and prostaglandin E(2) receptors 2 and 3 (EP2 and EP3) within bovine cumulus-oocyte complexes (COCs) and denuded oocytes and investigate the influence of gonadotropins, serum, and cumulus cell expansion on the abundance of transcripts encoding these genes.

DESIGN: Prospective controlled animal study.

SETTING: University research laboratory.

PATIENT(S): Animal models for human studies.

INTERVENTION(S): Cumulus-oocyte complexes were treated in culture with serum and gonadotropin-supplemented media to examine the effects to mRNA transcript levels.

MAIN OUTCOME MEASURE(S): Variation in mRNA transcript levels. …


The Gamma-Subunit Of The Na-K-Atpase As A Potential Regulator Of Apical And Basolateral Na+-Pump Isozymes During Development Of Bovine Pre-Attachment Embryos., L C Barcroft, S E Gill, A J Watson Sep 2002

The Gamma-Subunit Of The Na-K-Atpase As A Potential Regulator Of Apical And Basolateral Na+-Pump Isozymes During Development Of Bovine Pre-Attachment Embryos., L C Barcroft, S E Gill, A J Watson

Obstetrics & Gynaecology Publications

Expression and activity of the Na-K-ATPase within the basolateral membrane domains of the trophectoderm epithelium provide the driving force for accumulation of Na(+) and Cl(-) across the nascent epithelium, mediating fluid movement into the forming blastocoel. Within the trophectoderm of the bovine blastocyst, multiple isozymes of the Na-K-ATPase are expressed. Immunolocalization has demonstrated that the alpha1-isozyme localizes within the basolateral membrane, whereas the alpha 3-isozyme localizes to the apical cell margins. Gene-specific RT-PCR and wholemount indirect immunofluorescence confocal laser scanning microscopy were used to examine expression of the Na-K-ATPase gamma-subunit (a regulatory subunit of the Na-K-ATPase) throughout development of bovine …


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 Jun 2000

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 …