47 research outputs found
Amino acids in the uterine luminal fluid reflects the temporal changes in transporter expression in the endometrium and conceptus during early pregnancy in cattle
In cattle, conceptus-maternal interactions are critical for the establishment and maintenance of pregnancy. A major component of this early interaction involves the transport of nutrients and secretion of key molecules by uterine epithelial cells to help support conceptus development during the peri-implantation period of pregnancy. Objectives were to: 1) analyze temporal changes in the amino acid (AA) content of uterine luminal fluid (ULF) during the bovine estrous cycle; 2) understand conceptus-induced alterations in AA content; 3) determine expression of AA transporters in the endometrium and conceptus; and 4) determine how these transporters are modulated by (Progesterone) P4. Concentrations of aspartic acid, arginine, glutamine, histidine, lysine, isoleucine, leucine, phenylalanine and tyrosine decreased on Day 16 of the estrous cycle but increased on Day 19 in pregnant heifers (P < 0.05). Glutamic acid only increased in pregnant heifers on Day 19 (P,0.001). Asparagine concentrations were greater in ULF of cyclic compared to pregnant heifers on Day 7 (P < 0.05) while valine concentrations were higher in pregnant heifers on Day 16 (P < 0.05). Temporal changes in expression of the cationic AA transporters SLC7A1 SLC7A4 and SLC7A6 occurred in the endometrium during the estrous cycle/early pregnancy coordinate with changes in conceptus expression of SLC7A4, SLC7A2 and SLC7A1 (P < 0.05). Only one acidic AA transporter (SLC1A5) increased in the endometrium while conceptus expression of SLC1A4 increased (P < 0.05). The neutral AA transporters SLC38A2 and SLC7A5 increased in the endometrium in a temporal manner while conceptus expression of SLC38A7, SLC43A2, SLC38A11 and SLC7A8 also increased (P < 0.05). P4 modified the expression of SLC1A1, -1A4, -1A5, -38A2 , -38A4, -38A7, -43A2, -6A14, -7A1, -7A5 and -7A7 in the endometrium. Results demonstrate that temporal changes in AA in the ULF reflect changes in transporter expression in the endometrium and conceptus during early pregnancy in cattle, some of which are modified by P4. © 2014 Forde et al
Effect of Exposure to Seminal Plasma Through Natural Mating in Cattle on Conceptus Length and Gene Expression
peer-reviewedA growing body of evidence suggests that paternal factors have an impact on offspring
development. These studies have been mainly carried out in mice, where seminal
plasma (SP) has been shown to regulate endometrial gene expression and impact
embryo development and subsequent offspring health. In cattle, infusion of SP into
the uterus also induces changes in endometrial gene expression, however, evidence
for an effect of SP on early embryo development is lacking. In addition, during natural
mating, the bull ejaculates in the vagina; hence, it is not clear whether any SP reaches
the uterus in this species. Thus, the aim of the present study was to determine whether
SP exposure leads to improved early embryo survival and developmental rates in cattle.
To this end, Day 7 in vitro produced blastocysts were transferred to heifers (12–15 per
heifer) previously mated to vasectomized bulls (n = 13 heifers) or left unmated (n = 12
heifers; control). At Day 14, heifers were slaughtered, and conceptuses were recovered
to assess size, morphology and expression of candidate genes involved in different
developmental pathways. Additionally, CL volume at Day 7, and weight and volume
of CL at Day 14 were recorded. No effect of SP on CL volume and weight not on
conceptus recovery rate was observed. However, filamentous conceptuses recovered
from SP-exposed heifers were longer in comparison to the control group and differed
in expression of CALM1, CITED1, DLD, HNRNPDL, PTGS2, and TGFB3. In conclusion,
data indicate that female exposure to SP during natural mating can affect conceptus
development in cattle. This is probably achieved through modulation of the female
reproductive environment at the time of mating.
Keywords: seminal plasma, embryo development, corpus luteu
Machine-learning methods applied to integrated transcriptomic data from bovine blastocysts and elongating conceptuses to identify genes predictive of embryonic competence
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
TMEM95 is a sperm membrane protein essential for mammalian fertilization.
The fusion of gamete membranes during fertilization is an essential process for sexual reproduction. Despite its importance, only three proteins are known to be indispensable for sperm-egg membrane fusion: the sperm proteins IZUMO1 and SPACA6, and the egg protein JUNO. Here we demonstrate that another sperm protein, TMEM95, is necessary for sperm-egg interaction. TMEM95 ablation in mice caused complete male-specific infertility. Sperm lacking this protein were morphologically normal exhibited normal motility, and could penetrate the zona pellucida and bind to the oolemma. However, once bound to the oolemma, TMEM95-deficient sperm were unable to fuse with the egg membrane or penetrate into the ooplasm, and fertilization could only be achieved by mechanical injection of one sperm into the ooplasm, thereby bypassing membrane fusion. These data demonstrate that TMEM95 is essential for mammalian fertilization. © 2020, Lamas-Toranzo et al
The Grizzly, October 2, 1981
Homecoming Celebration Takes on New Meaning • Previously Idle Appeals Procedure Finally Tested • Faculty Member\u27s Dismissal Creates Unrest • President Calls School Start \u27One of the Best Ever\u27 • Comment: I Thought This Was College • Parent Involvement Sought in Planning for the Future • Platforms for Freshman Class Elections • Greaseband Sings its Heart Out to Fortunate Few • Concert Causes Funds Loss • Transplanted Texan: Our Most Illustrious Non-Graduate • Rolling Stones Rock \u27n Roll Circus Levels JFK • Ursinus News Briefs: Postage hike finally granted; \u27Dealing with Stress\u27 offered by evening school • Campus Craziness: Sorority Pledging Begins • Red Cross Bloodmobile at HH • Women Receive Special Attention for Founder\u27s Day • Parents Day: Oct. 10 • Volleyball Holding Even • Soccer Registers First Win • Bears Surrender Lead to Tie Moravian at 10 • Hockey Pulls Out Win in Last Seconds • X-Country Makes it Look Easy . . . Againhttps://digitalcommons.ursinus.edu/grizzlynews/1062/thumbnail.jp
Do differences in the endometrial transcriptome between uterine horns ipsilateral and contralateral to the corpus luteum influence conceptus growth to day 14 in cattle?
peer-reviewedEmbryo transfer to the uterine horn contralateral to the ovary containing the corpus luteum (CL)
negatively impacts pregnancy establishment in cattle. Our aim was to compare the transcriptome
and ability of the ipsilateral and contralateral uterine horns to support preimplantation conceptus
survival and growth to day 14. In experiment 1, endometrial samples from both horns were collected from synchronized heifers slaughtered on day 5, 7, 13, or 16 post-estrus (n = 5 per time)
and subjected to RNA sequencing. In experiment 2, 10 day 7 in vitro produced blastocysts were
transferred into the uterine horn ipsilateral (n = 9) or contralateral to the CL (n = 8) or into both
horns (i.e., bilateral, n = 9) of synchronized recipient heifers. Reproductive tracts were recovered
at slaughter on day 14, and the number and dimensions of recovered conceptuses were recorded
for each horn. A total of 217, 54, 14, and 18 differentially expressed genes (>2-fold change, FDR
P < 0.05) were detected between ipsilateral and contralateral horns on days 5, 7, 13, and 16, respectively, with signaling pathways regulating pluripotency of stem cells, ErbB signaling pathway,
and mTOR signaling pathway amongst the top canonical pathways. Site of embryo transfer did
not affect recovery rate (48.0%, 168/350) or length of conceptuses (mean ± SE 2.85 ± 0.27 mm).
Although differences in gene expression exist between the endometrium of uterine horns ipsilateral and contralateral to the CL in cattle, they do not impact conceptus survival or length between
day 7 and 14.Science Foundation Irelan
Invited review: Use of assisted reproduction techniques to accelerate genetic gain and increase value of beef production in dairy herds
peer-reviewedThe contribution of the calf enterprise to the profit of the dairy farm is generally considered small, with beef bull selection on dairy farms often not considered a high priority. However, this is likely to change in the future as the rapid rate of expansion of the dairy herd in some countries is set to plateau and improvements in dairy herd fertility combine to reduce the proportion of dairy breed calves required on dairy farms. This presents the opportunity to increase the proportion of beef breed calves born, increasing both the value of calf sales and the marketability of the calves. Beef embryos could become a new breeding tool for dairies as producers need to reassess their breeding policy as a consequence of welfare concerns and poor calf prices. Assisted reproductive technologies can contribute to accelerated genetic gain by allowing an increased number of offspring to be produced from genetically elite dams. There are the following 3 general classes of donor females of interest to an integrated dairy-beef system: (1) elite dairy dams, from which oocytes are recovered from live females using ovum pick-up and fertilized in vitro with semen from elite dairy bulls; (2) elite beef dams, where the oocytes are recovered from live females using ovum pick-up and fertilized with semen from elite beef bulls; and (3) commercial beef dams (≥50% beef genetics), where ovaries are collected from the abattoir postslaughter, and oocytes are fertilized with semen from elite beef bulls that are suitable for use on dairy cows (resulting embryo with ≥75% beef genetics). The expected benefits of these collective developments include accelerated genetic gain for milk and beef production in addition to transformation of the dairy herd calf crop to a combination of good genetic merit dairy female calves and premium-quality beef calves. The aim of this review is to describe how these technologies can be harnessed to intensively select for genetic improvement in both dairy breed and beef breed bulls suitable for use in the dairy herd
Dose- and time-dependent effects of interferon tau on bovine endometrial gene expression
International bull fertility conference – theory to practice, westport, ireland, 2018
Editorial Conference ProceedingsThis supplement to Animal contains the papers associated with the keynote lectures delivered at the International Bull Fertility Conference – Theory to Practice held in Westport, Ireland from May 27th to 30th 2018.
The conference was organised under the auspices of the British Society of Animal Science (BSAS) in close collaboration with Teagasc, University College Dublin, University of Limerick, the Cattle Association of Veterinary Ireland (CAVI), XL Vets, the British
Cattle Veterinary Association (BCVA) and the Department of Agriculture Food and the Marine