Presence of Clock genes in equine full-term placenta.
Abstract: Mammals have a circadian rhythm that is synchronized by a master clock located in the hypothalamic suprachiasmatic nucleus (SCN). The SCN regulates additional clocks located in peripheral tissues, including some involved in endocrine or reproductive functions. Studies in humans and mice report that molecular clocks also exist in the placenta. However, little is known about the presence of "Clock genes," namely Circadian Locomotor Output Cycles Kaput (CLOCK), Brain and Muscle Arnt-Like 1 (BMAL1), Period 1 (PER1), Period 2 (PER2), Cryptochrome 1 (CRY1), and Cryptochrome 2 (CRY2), in equine placenta. Pregnancy length in mares varies and shows fluctuations in hormone concentrations throughout pregnancy. We postulate that similar to humans and mice, Clock genes are present in the horse placentas. Our goal was to determine if relative levels of clock genes were different between placentas associated with males and female fetuses or correlated with gestational length. We used polymerase chain reaction and immunofluorescence to study the presence of CLOCK, BMAL1, PER1, PER2, CRY1, and CRY2 in full-term mare placentas. Clock genes were present in all placentas, with significant lower levels of CRY2 and CLOCK in placentas that were associated with male fetuses. There was no association between relative levels of Clock genes and gestational length. These data provide the stage for future studies aimed at uncovering a function for Clock genes in the horse placenta.
© The Author(s) 2020. Published by Oxford University Press on behalf of the American Society of Animal Science. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Publication Date: 2020-03-27 PubMed ID: 32211788PubMed Central: PMC7149551DOI: 10.1093/jas/skaa094Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- Journal Article
Summary
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
This research reveals that clock genes, which help regulate circadian rhythm, are also present in equine placenta. The presence of these genes did not seem to correlate with gestational length, but lower levels of certain clock genes were observed in placentas associated with male fetuses.
Background
- The circadian rhythm in mammals are governed by a ‘master clock’ present in the hypothalamic suprachiasmatic nucleus (SCN).
- This master clock controls additional subsidiary clocks located in various parts of the body, particularly tissues involved in endocrine or reproductive processes.
- Earlier research on humans and mice reveals the presence of these subsidiary clocks, often termed as “Clock genes,” in the placenta as well.
- The six clock genes are identified as Circadian Locomotor Output Cycles Kaput (CLOCK), Brain and Muscle Arnt-Like 1 (BMAL1), Period 1 (PER1), Period 2 (PER2), Cryptochrome 1 (CRY1), and Cryptochrome 2 (CRY2).
- Despite the knowledge on their existence in humans and mice, there isn’t much knowledge about their existence in equine placenta.
The Study
- Pregnancy in mares shows significant variation and fluctuation in hormone levels, leading researchers to speculate the presence of Clock genes in horse placentas as well.
- The researchers studied the presence of these six clock genes in full-term horse placentas using two techniques – polymerase chain reaction and immunofluorescence methods.
- They also sought to understand if the relative levels of these clock genes differed between placentas associated with male and female fetuses and if they had any correlation with the length of gestation.
Findings
- All six Clock genes were identified in every horse placenta that was studied.
- In placentas associated with male fetuses, there were significantly lower levels of the CLOCK and CRY2 genes.
- However, the research found no meaningful association between the relative levels of the Clock genes and the length of pregnancy.
- This sets the stage for further research into the potential functions and implications of Clock genes in equine reproduction.
Cite This Article
APA
Parsons Aubone AM, Bisiau CM, McCue PM, Bouma GJ.
(2020).
Presence of Clock genes in equine full-term placenta.
J Anim Sci, 98(4), skaa094.
https://doi.org/10.1093/jas/skaa094 Publication
Researcher Affiliations
- Animal Reproduction & Biotechnology Laboratory, Department of Biomedical Science, Colorado State University, Fort Collins, CO.
- Equine Reproduction Laboratory, Department of Clinical Sciences, Colorado State University, Fort Collins, CO.
- Equine Reproduction Laboratory, Department of Clinical Sciences, Colorado State University, Fort Collins, CO.
- Animal Reproduction & Biotechnology Laboratory, Department of Biomedical Science, Colorado State University, Fort Collins, CO.
MeSH Terms
- Animals
- CLOCK Proteins / genetics
- CLOCK Proteins / metabolism
- Female
- Gene Expression Regulation
- Horses / physiology
- Male
- Placenta / metabolism
- Pregnancy
References
This article includes 17 references
- Alibhai FJ, Reitz CJ, Peppler WT, Basu P, Sheppard P, Choleris E, Bakovic M, Martino TA. Female ClockΔ19/Δ19 mice are protected from the development of age-dependent cardiomyopathy.. Cardiovasc Res 2018 Feb 1;114(2):259-271.
- Balsalobre A, Brown SA, Marcacci L, Tronche F, Kellendonk C, Reichardt HM, Schütz G, Schibler U. Resetting of circadian time in peripheral tissues by glucocorticoid signaling.. Science 2000 Sep 29;289(5488):2344-7.
- Boden MJ, Kennaway DJ. Circadian rhythms and reproduction.. Reproduction 2006 Sep;132(3):379-92.
- Chappell PE, White RS, Mellon PL. Circadian gene expression regulates pulsatile gonadotropin-releasing hormone (GnRH) secretory patterns in the hypothalamic GnRH-secreting GT1-7 cell line.. J Neurosci 2003 Dec 3;23(35):11202-13.
- Davies Morel MC, Newcombe JR, Holland SJ. Factors affecting gestation length in the Thoroughbred mare.. Anim Reprod Sci 2002 Dec 16;74(3-4):175-85.
- Dascanio JJ, McCue PM. Equine reproductive procedures. 1st ed.Hoboken (NJ): Wiley & Sons, Inc; p. 248.
- Ginther OJ. Reproductive biology of the mare: basic and applied aspects. 2nd ed.Cross Plains (WI): Equiservices.
- Gómez-Abellán P, Madrid JA, Luján JA, Frutos MD, González R, Martínez-Augustín O, de Medina FS, Ordovás JM, Garaulet M. Sexual dimorphism in clock genes expression in human adipose tissue.. Obes Surg 2012 Jan;22(1):105-12.
- Lim AS, Myers AJ, Yu L, Buchman AS, Duffy JF, De Jager PL, Bennett DA. Sex difference in daily rhythms of clock gene expression in the aged human cerebral cortex.. J Biol Rhythms 2013 Apr;28(2):117-29.
- Lowrey PL, Takahashi JS. Genetics of circadian rhythms in Mammalian model organisms.. Adv Genet 2011;74:175-230.
- Pérez S, Murias L, Fernández-Plaza C, Díaz I, González C, Otero J, Díaz E. Evidence for clock genes circadian rhythms in human full-term placenta.. Syst Biol Reprod Med 2015;61(6):360-6.
- Ratajczak CK, Fay JC, Muglia LJ. Preventing preterm birth: the past limitations and new potential of animal models.. Dis Model Mech 2010 Jul-Aug;3(7-8):407-14.
- Ratajczak CK, Herzog ED, Muglia LJ. Clock gene expression in gravid uterus and extra-embryonic tissues during late gestation in the mouse.. Reprod Fertil Dev 2010;22(5):743-50.
- Reiter RJ, Tan DX, Korkmaz A, Rosales-Corral SA. Melatonin and stable circadian rhythms optimize maternal, placental and fetal physiology.. Hum Reprod Update 2014 Mar-Apr;20(2):293-307.
- Rusak B, Zucker I. Neural regulation of circadian rhythms.. Physiol Rev 1979 Jul;59(3):449-526.
- Nagy P, Guillaume D, Daels P. Seasonality in mares.. Anim Reprod Sci 2000 Jul 2;60-61:245-62.
- Wu TC, Wan YJ, Damjanov I. Fluorescein-conjugated Bandeiraea simplicifolia lectin as a marker of endodermal, yolk sac, and trophoblastic differentiation in the mouse embryo.. Differentiation 1983;24(1):55-9.
Citations
This article has been cited 2 times.- Joyce JD, Moore GA, Goswami P, Harrell TL, Taylor TM, Hawks SA, Green JC, Jia M, Irwin MD, Leslie E, Duggal NK, Thompson CK, Bertke AS. SARS-CoV-2 Rapidly Infects Peripheral Sensory and Autonomic Neurons, Contributing to Central Nervous System Neuroinvasion before Viremia. Int J Mol Sci 2024 Jul 28;25(15).
- Morales-Vázquez MM, Meza-Serrano E, Lara-Pereyra I, Acuña-González RJ, Alonso-Morales R, Hayen-Valles S, Boeta AM, Zarco L, Lozano-Cuenca J, López-Canales JS, Flores-Herrera H. Equine Placentitis in Mares Induces the Secretion of Pro-Inflammatory Cytokine eIL-1β and the Active Extracellular Matrix Metalloproteinase (MMP)-9. Vet Sci 2023 Aug 22;10(9).
Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists
