Comparison of gene expression in individual preimplantation bovine embryos produced by in vitro fertilisation or somatic cell nuclear transfer

2005 ◽  
Vol 17 (5) ◽  
pp. 487 ◽  
Author(s):  
Luiz Sergio de A. Camargo ◽  
Anne M. Powell ◽  
Vicente R. do Vale Filho ◽  
Robert J. Wall
Keyword(s):  
Gene Expression ◽  
Somatic Cell Nuclear Transfer ◽  
Nuclear Transfer ◽  
Blastocyst Stage ◽  
In Vitro Fertilisation ◽  
Developmental Abnormalities ◽  
Aberrant Gene Expression ◽  
Aberrant Gene

In vitro fertilisation (IVF) and somatic cell nuclear transfer (SCNT) have been implicated in a variety of developmental abnormalities. Aberrant gene expression is likely to account for much of the diminished viability and developmental abnormalities observed. In the present study, the expression of multiple genes in IVF and SCNT bovine blastocyst-stage embryos were evaluated and compared with in vivo-produced embryos. Eleven genes expressed at and following maternal–zygotic transcription transition were evaluated in individual blastocysts by real-time polymerase chain reaction following RNA amplification. A subset of those genes was also evaluated in individual IVF and SCNT eight-cell embryos. A fibroblast-specific gene, expressed by nuclear donor cells, was also evaluated in IVF and SCNT embryos. The observed gene expression pattern at the eight-cell stage was not different between IVF and SCNT embryos (P > 0.05). In vitro fertilisation and SCNT blastocyst expression was lower (P < 0.01) for all genes compared with their in vivo-produced counterparts, except for lactate dehydrogenase isoenzyme A (P < 0.001). The patterns of gene expression of the IVF and SCNT blastocysts were indistinguishable. Neither SCNT eight-cell nor blastocyst-stage embryos expressed the gene used as a fibroblast marker (collagen VIα1). For the genes evaluated, the level of expression was influenced more by the environment than by the method used to produce the embryos. These results support the notion that if developmental differences observed in IVF- and SCNT-produced fetuses and neonates are the result of aberrant gene expression during the preimplantation stage, those differences in expression are subtle.

scholarly journals Chromatin Modifying Agents in theIn VitroProduction of Bovine Embryos

2011 ◽  
Vol 2011 ◽  
pp. 1-9 ◽  
Author(s):  
Fabio Morato Monteiro ◽  
Clara Slade Oliveira ◽  
Letícia Zoccolaro Oliveira ◽  
Naiara Zoccal Saraiva ◽  
Maria Eugênia Zerlotti Mercadante ◽  
...  
Keyword(s):  
Gene Expression ◽  
Nuclear Transfer ◽  
Epigenetic Reprogramming ◽  
Nuclear Reprogramming ◽  
Bovine Embryos ◽  
Aberrant Gene Expression ◽  
Low Efficiency ◽  
Aberrant Gene

The low efficiency observed in cloning by nuclear transfer is related to an aberrant gene expression following errors in epigenetic reprogramming. Recent studies have focused on further understanding of the modifications that take place in the chromatin of embryos during the preimplantation period, through the use of chromatin modifying agents. The goal of these studies is to identify the factors involved in nuclear reprogramming and to adjustin vitromanipulations in order to better mimicin vivoconditions. Therefore, proper knowledge of epigenetic reprogramming is necessary to prevent possible epigenetic errors and to improve efficiency and the use ofin vitrofertilization and cloning technologies in cattle and other species.

27 SOMATIC CELL NUCLEAR TRANSFER CLONING AND EMBRYO AGGREGATION IN PIGS

2014 ◽  
Vol 26 (1) ◽  
pp. 128
Author(s):  
C. P. Buemo ◽  
A. Gambini ◽  
I. Hiriart ◽  
D. Salamone
Keyword(s):  
In Vitro Culture ◽  
Somatic Cell ◽  
Embryo Development ◽  
Somatic Cell Nuclear Transfer ◽  
Nuclear Transfer ◽  
Electric Pulse ◽  
Blastocyst Stage ◽  
Control Group

Somatic cell nuclear transfer (SCNT) derived blastocysts have lower cell number than IVF-derived blastocysts and their in vivo counterparts. The aim of this study was to improve the blastocyst rates and quality of SCNT blastocysts by the aggregation of genetically identical free zona pellucida (ZP) porcine clones. Cumulus–oocyte complexes were recovered from slaughterhouse ovaries by follicular aspiration. Maturation was performed in TCM for 42 to 48 h at 39°C and 5% CO2. After denudation by treatment with hyaluronidase, mature oocytes were stripped of the ZP using a protease and then enucleated by micromanipulation; staining was performed with Hoechst 33342 to observe metaphase II. Ooplasms were placed in phytohemagglutinin to permit different membranes to adhere between each other; the ooplasm membrane was adhered to a porcine fetal fibroblast from an in vitro culture. Adhered membranes of the donor cell nucleus and enucleated oocyte cytoplasm were electrofused through the use of an electric pulse (80 V for 30 μs). All reconstituted embryos (RE) were electrically activated using an electroporator in activation medium (0.3 M mannitol, 1.0 mM CaCl2, 0.1 mM MgCl2, and 0.01% PVA) by a DC pulse of 1.2 kV cm–1 for 80 μs. Then, the oocytes were incubated in 2 mM 6-DMAP for 3 h. In vitro culture of free ZP embryos was achieved in a system of well of wells in 100 μL of medium, placing 3 activated oocytes per microwell (aggregation embryo), whereas the control group was cultivated with equal drops without microwells. Embryos were cultivated at 39°C in 5% O2, 5% CO2 for 7 days in SOF medium with a supplement of 10% fetal bovine serum on the fifth day. The RE were placed in microwells. Two experimental groups were used, control group (not added 1X) and 3 RE per microwell (3X). At Day 7, resulting blastocysts were classified according to their morphology and diameter to determine their quality and evaluate if the embryo aggregation improves it. Results demonstrated that aggregation improves in vitro embryo development rates until blastocyst stage and indicated that blastocysts rates calculated over total number of oocytes do not differ between groups (Table 1). Embryo aggregation improves cleavage per oocyte and cleavage per microwell rates, presenting statistical significant differences and increasing the probabilities of higher embryo development generation until the blastocyst stage with better quality and higher diameter. Table 1.Somatic cell nuclear transfer cloning and embryo aggregation

Comparative expression analysis of embryonic development-related genes at different stages of parthenogenetic and in vitro fertilized embryos in caprine

Zygote ◽  
2013 ◽  
Vol 23 (2) ◽  
pp. 198-204 ◽  
Author(s):  
Renu Singh ◽  
Kuldeep Kumar ◽  
R. Ranjan ◽  
Manish Kumar ◽  
T. Yasotha ◽  
...  
Keyword(s):  
Gene Expression ◽  
Developmental Competence ◽  
Cell Stage ◽  
Developmental Abnormalities ◽  
Aberrant Gene Expression ◽  
Comparative Expression Analysis ◽  
Morula Stage ◽  
Aberrant Gene ◽  
Parthenogenetic Embryos

SummaryAberrant gene expression occurs in parthenogenetic embryos due to abnormal epigenetic modifications in the genome that probably diminish viability and enhance developmental abnormalities in these embryos. In the present study, five developmentally important genes (HPRT1, Cx43, Sox2, Mest and IGF2R) were analysed at different stages in parthenotes (haploid and diploid) and compared with similar stages in in vitro fertilized (IVF) embryos. The results indicated that in haploid parthenotes expression of HPRT1 was upregulated (P < 0.05) only at the 2–4-cell stage whereas Cx43 expression was significantly (P < 0.05) downregulated in all stages as compared with the control. However, expression of this gene was upregulated (P < 0.05) in 2–4-cell and morula stages of diploid parthenotes. Expression of Sox2 was significantly (P < 0.05) downregulated in morula stage haploid parthenotes, whereas it was upregulated (P < 0.05) in 8–16-cell stage diploid embryos. The expression of Mest was upregulated (P < 0.05) at the 2–4-cell stage of both haploid and diploid parthenotes, whereas it was downregulated in 8–16-cell stage diploid embryos as compared with control. IGF2R expression was upregulated (P < 0.05) only in morula stage haploid and diploid parthenote as compared with control. These results indicate that parthenogenetic embryos showed aberrant gene expression of developmentally important genes such as HPRT1, Cx43, Sox2, Mest and IGF2R in comparison with IVF embryos, this finding may be one of the major reasons for the poor developmental competence of parthenogenetic embryos.

260 COMPREHENSIVE IDENTIFICATION OF RELATIVE GENES CAUSING ABNORMAL DEVELOPMENT OF BOVINE EMBRYOS PRODUCED BY SOMATIC CELL NUCLEAR TRANSFER

2006 ◽  
Vol 18 (2) ◽  
pp. 237
Author(s):  
J. Park ◽  
N. Minami ◽  
H. Imai
Keyword(s):  
Gene Expression ◽  
In Vitro Fertilization ◽  
Somatic Cell ◽  
Differentially Expressed Genes ◽  
Somatic Cell Nuclear Transfer ◽  
Nuclear Transfer ◽  
Blastocyst Stage ◽  
Differentially Expressed ◽  
Vitro Fertilization

Developmental failure of a cloned animal using somatic cell nuclear transfer (SCNT) procedures is considered to be the result of abnormal expression of developmentally important genes caused by incomplete reprogramming of the donor cell nuclei. However, there are few reports about stage-specific gene expression during cleavage progression of cloned embryos. The aim of this study was to identify using fluorescein differential display method, the differentially expressed genes in cloned embryos at early developmental stages compared with those produced by in vitro fertilization. Bovine cumulus-oocytes complexes (COCs) were aspirated from follicles (2-8 mm in diameter) of slaughterhouse ovaries and cultured in TCM-199 supplemented with 10% fetal calf serum (FCS) for 18 h for somatic cell nuclear transfer (NT) or 24 h for in vitro fertilization (IVF) at 39�C. Removal of oocyte nuclei for NT was performed by squeezing out a small amount of the cytoplasm laying beneath the first polar body by means of a glass needle. Donor cells for NT were obtained from skin cells of an adult cow and cultured in DMEM supplemented with 10% FCS. After the transfer of somatic cell into enucleated oocytes, DC electric pulses at 200 V/mm for 2 � 10 �s were used for fusion, and the reconstructed embryos were treated with 10 �g/mL cycloheximide for 6 h. The embryos were then cultured for 120 h (morula stage) or 168 h (blastocyst stage) in modified SOF medium under 5% CO2, 5% O2 and 90% N2 at 39�C. Total RNA obtained from NT and IVF embryos were analyzed by differential display RT-PCR (DDRT-PCR) as previously described (Minami et al. 2001 Biol. Reprod. 64, 30-35). We obtained several differences in gene expression patterns between NT and IVF embryos at the morula and blastocyst stage. A total of 52 cDNA fragments were isolated and analyzed. Semiquantitative analysis revealed that some genes (NADH dehydrogenase subunit 1, SR rich protein, KIAA0107, ribosomal protein L19) were highly expressed in IVF embryos compared with NT embryos, whereas other genes (CASK) were highly expressed in NT embryos compared with IVF embryos. These results indicate that the differentially expressed genes observed in NT embryos may be representative of marker genes for the production of normal NT offspring and DDRT-PCR procedure is quite useful for identification of several genes that are differentially expressed between NT and IVF embryos.Although the detailed function of the genes and their products remains to be determined, it is likely that the reprogramming mechanisms can be elucidated genetically by the analysis of differentially expressed genes in the future.

Differential effects of culture and nuclear transfer on relative transcript levels of genes with key roles during preimplantation

Zygote ◽  
2006 ◽  
Vol 14 (1) ◽  
pp. 81-87 ◽  
Author(s):  
P.N. Moreira ◽  
R. Fernández-Gonzalez ◽  
M.A. Ramirez ◽  
M. Pérez-Crespo ◽  
D. Rizos ◽  
...  
Keyword(s):  
Nuclear Transfer ◽  
Culture Medium ◽  
Cumulus Cell ◽  
Blastocyst Stage ◽  
Mrna Levels ◽  
Differential Effects ◽  
Glut 1 ◽  
Mouse Somatic Cell

It is well known that the preimplantation culture environment to which embryos are exposed influences the expression of developmentally important genes. Recently, it has been reported that MEMα, a culture medium commonly used for somatic cells, allows high rates of preimplantation development and development to term of mouse somatic cell nuclear transfer (SCNT) embryos. The objective of this study was to compare the differential effects of this medium and of the nuclear transfer procedure on the relative mRNA abundance of several genes with key roles during preimplantation. The relative mRNA levels of nine genes (Glut 1, Glut 5, G6PDH, Bax, Survivin, Gpx 1, Oct4, mTert and IGF2bp1) were quantified at blastocyst stage on cumulus cell cloned embryos cultured in MEMα, as well as on in vivo cultured and MEMα cultured controls. Only three of the nine transcripts analysed (Glut 5, Gpx 1 and Igf2bp1) were significantly down-regulated at blastocyst stage in in vitro produced controls. However, most genes analysed in our MEMα cultured cloned embryos showed altered transcription levels. Interestingly, between cloned and in vitro produced controls only the transcription levels measured for Glut 1 were significantly different. This result suggests that Glut 1 may be a good marker for embryo quality after cumulus cell nuclear transfer.

scholarly journals Simultaneous gene quantitation of multiple genes in individual bovine nuclear transfer blastocysts

Reproduction ◽  
2007 ◽  
Vol 133 (1) ◽  
pp. 231-242 ◽  
Author(s):  
Craig Smith ◽  
Debbie Berg ◽  
Sue Beaumont ◽  
Neil T Standley ◽  
David N Wells ◽  
...  
Keyword(s):  
Gene Expression ◽  
Nuclear Transfer ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Ectopic Expression ◽  
Cell Number ◽  
Transcript Levels ◽  
Multiple Genes

During somatic cell nuclear transfer (NT), the transcriptional status of the donor cell has to be reprogrammed to reflect that of an embryo. We analysed the accuracy of this process by comparing transcript levels of four developmentally important genes (Oct4,Otx2,Ifitm3,GATA6), a gene involved in epigenetic regulation (Dnmt3a) and three housekeeping genes (β-actin, β-tubulinandGAPDH) in 21 NT blastocysts with that in genetically half-identicalin vitroproduced (IVP,n=19) andin vivo(n=15) bovine embryos. We have optimised an RNA-isolation and SYBR-green-based real-time RT-PCR procedure allowing the reproducible absolute quantification of multiple genes from a single blastocyst. Our data indicated that transcript levels did not differ significantly between stage and grade-matched zona-free NT and IVP embryos except for Ifitm3/Fragilis, which was expressed at twofold higher levels in NT blastocysts.Ifitm3expression is confined to the inner cell mass at day 7 blastocysts and to the epiblast in day 14 embryos. No ectopic expression in the trophectoderm was seen in NT embryos. Gene expression in NTand IVP embryos increased between two- and threefold for all eight genes from early to late blastocyst stages. This increase exceeded the increase in cell number over this time period indicating an increase in transcript number per cell. Embryo quality (morphological grading) was correlated to cell number for NT and IVP embryos with grade 3 blastocysts containing 30% fewer cells. However, only NT embryos displayed a significant reduction in gene expression (50%) with loss of quality. Variability in gene expression levels was not significantly different in NT, IVP orin vivoembryos but differed among genes, suggesting that the stringency of regulation is intrinsic to a gene and not affected by culture or nuclear transfer.Oct4levels exhibited the lowest variability. Analysing the total variability of all eight genes for individual embryos revealed thatin vivoembryos resembled each other much more than did NT and IVP blastocysts. Furthermore,in vivoembryos, consisting of 1.5-fold more cells, generally contained two- to fourfold more transcripts for the eight genes than did their cultured counterparts. Thus, culture conditions (in vivoversusin vitro) have greater effects on gene expression than does nuclear transfer when minimising genetic heterogeneity.

Overexpression of MicroRNA-29b Decreases Expression of DNA Methyltransferases and Improves Quality of the Blastocysts Derived from Somatic Cell Nuclear Transfer in Cattle

2018 ◽  
Vol 24 (1) ◽  
pp. 29-37 ◽  
Author(s):  
Shuang Liang ◽  
Zheng-Wen Nie ◽  
Jing Guo ◽  
Ying-Jie Niu ◽  
Kyung-Tae Shin ◽  
...  
Keyword(s):  
Somatic Cell ◽  
Somatic Cell Nuclear Transfer ◽  
Nuclear Transfer ◽  
Cellular Proliferation ◽  
Dna Methyltransferases ◽  
Blastocyst Stage ◽  
Developmental Competence ◽  
Somatic Cell Reprogramming

AbstractMicroRNA (miR)-29b plays a crucial role during somatic cell reprogramming. The aim of the current study was to explore the effects of miR-29b on the developmental competence of bovine somatic cell nuclear transfer (SCNT) embryos, as well as the underlying mechanisms of action. The expression level of miR-29b was lower in bovine SCNT embryos at the pronuclear, 8-cell, and blastocyst stages compared within vitrofertilized embryos. In addition, miR-29b regulates the expression of DNA methyltransferases (Dnmt3a/3bandDnmt1) in bovine SCNT embryos. We further investigated SCNT embryo developmental competence and found that miR-29b overexpression during bovine SCNT embryonic development does not improve developmental potency and downregulation inhibits developmental potency. Nevertheless, the quality of bovine SCNT embryos at the blastocyst stage improved significantly. The expression of pluripotency factors and cellular proliferation were significantly higher in blastocysts from the miR-29b overexpression group than the control and downregulation groups. In addition, outgrowth potential in blastocysts after miR-29b overexpression was also significantly greater in the miR-29b overexpression group than in the control and downregulation groups. Taken together, these results demonstrated that miR-29b plays an important role in bovine SCNT embryo development.

41 STUDY ON THE ESTABLISHMENT OF SOMATIC CELL NUCLEAR TRANSFER USING IN VIVO-MATURED OOCYTES IN DOGS

2006 ◽  
Vol 18 (2) ◽  
pp. 129 ◽  
Author(s):  
G. Jang ◽  
M. Kim ◽  
H. J. Oh ◽  
F. Y. Heru ◽  
M. S. Hossein ◽  
...  
Keyword(s):  
Electrical Stimulation ◽  
Somatic Cell Nuclear Transfer ◽  
Nuclear Transfer ◽  
Chemical Activation ◽  
Developmental Competence ◽  
Perivitelline Space ◽  
Parthenogenetic Activation ◽  
Vaginal Cytology

The present study was performed to collect in vivo matured canine oocytes for somatic cell nuclear transfer (SCNT) and to investigate the developmental competence of canine parthenogenetic and SCNT embryos as the preliminary research for producing cloned dog. The day of ovulation as described by Hase et al. (2000 J. Vet. Med. Sci. 62, 243-248) was determined by serum progesterone levels and at that time vaginal cytology was performed to assess the cornified index. In vivo-matured oocytes were recovered by retrograde flushing of the oviducts at around 48 h (n = 20) or 72 h (n = 25) after the estimated time of ovulation. Overall size of each oocyte, as well as ooplasmic diameter, zona pellucida thickness, and perivitelline space width, was determined after removing the cumulus cells by pipetting (Exp. 1). To determine activation protocols, two treatments, (1) chemical activation (10 �M Ca ionophore for 4 min, followed by incubation for 4 h with 1.9 mM 6-dimethylaminopurine) and (2) electrical stimulation (3.1?3.4 kV/cm in 0.25M mannitol solution), were evaluated to induce parthenogenetic activation of oocytes (Exp. 2). Donor cells were obtained from the primary cell culture of a canine ear skin biopsy, and SCNT was performed according to our laboratory procedures (Jang et al. 2004 Theriogenology 62, 512-521). Three voltages (1.7?2.0 kV/cm, 2.1-2.4 kV/cm, and 3.1-3.4 kV/cm) were tested for fusion. The fused couplets were subjected to chemical or electrical stimulation as in parthenogenetic activation and in vitro developmental competence was monitored (Exp. 3). As a result, more in vivo-matured canine oocytes were obtained at 72 h (92%) than at 48 h (15%) after ovulation; the 72-h occytes had progesterone concentrations of 4-8 ng/mL and a cornified index (vaginal cytology) of 83.34. The average number of oocytes recovered was 12 and sizes of ooplasmic diameter, cytoplasm, zona pellucida, and perivitelline space in in vivo canine-matured oocytes (n = 120) were 178.8 � 9.3 �m, 125.0 � 8.2 �m, 21.7 � 3.7 �m, and 12.7 � 3.5 �m, respectively. Parthenogenetically activated oocytes developed to the 16-cell and morula stages, but failed to develop to the blastocyst stage. Among the three voltages, in the highest voltage (75.2%) the number of fused couplets was increased compared to either of the other voltages (33.3% and 44.0%). Cleavage rates (60.9% vs. 58.0%) of cloned embryos were not significantly affected by method of activation. In terms of in vitro developmental competence, cloned embryos developed to the 16-cell or morula stage in vitro after electrical or chemical activation, respectively. In conclusion, in the present study we demonstrated that measurement of progesterone levels, in combination with evaluation of vaginal cytology, can be used to determine the estimated time of ovulation in bitches. In addition, we determined fusion/activation protocols that resulted in in vitro development of a portion of parthenogenetically activated and cloned embryos to the 16-cell and morula stages. This study was supported by grants from the Biogreen 21-1000520030100000.

68 GENE EXPRESSION COMPARISONS BETWEEN BOVINE IN VIVO AND CLONED EMBRYOS PRODUCED BY THREE DIFFERENT METHODS

2006 ◽  
Vol 18 (2) ◽  
pp. 142
Author(s):  
N. Ruddock ◽  
K. Wilson ◽  
M. Cooney ◽  
R. Tecirlioglu ◽  
V. Hall ◽  
...  
Keyword(s):  
Gene Expression ◽  
Chromatin Remodeling ◽  
Nuclear Transfer ◽  
Expression Patterns ◽  
Experimental Models ◽  
Gene Expression Patterns ◽  
Imprinted Genes ◽  
Mammalian Embryo

Developmental pathways in the mammalian embryo are profoundly influenced by the epigenetic interaction of the environment and the genome. Loss of epigenetic control has been implicated in aberrant gene expression and altered imprinting patterns with consequence to the physiology and viability of the conceptus. Bovine somatic cell nuclear transfer (SCNT) is contingent on in vitro culture, and both SCNT and culture conditions are known to induce changes in embryonic gene expression patterns. Using these experimental models, this study compared gene expression of Day 7 cloned blastocysts created from three different SCNT protocols using the same cell line, with Day 7 in vivo blastocysts to elucidate mechanisms responsible for variations in phenotypic outcomes. SCNT methods included: (1) traditional SCNT by subzonal injection (SI); (2) handmade cloning (HMC); and (3) modified serial nuclear transfer (SNT), developed within the group. Four imprinted genes (Grb10, Ndn, Nnat, and Ube3a), four chromatin remodeling genes (Cbx1, Cbx3, Smarca4, and Smarcb1) and two genes implicated in polycystic liver disease (Prkcsh and Sec63) were analyzed in single blastocysts from each treatment (n = 5). All blastocysts expressed Actin, Oct-4 and Ifn-tau. All genes were sequence verified. Several genes were expressed ubiquitously across all groups, including Ndn, Ube3a, Cbx1, Cbx3, and Smarcb1. Interestingly, Grb10 was not expressed in two HMCs and one SNT blastocyst. Nnat was weakly expressed in one in vivo blastocyst and in the majority of cloned blastocysts in all groups. Prkcsh and Sec63 were expressed in all but one HMC blastocyst. While gene expression patterns were mostly maintained following SCNT, the imprinted genes Nnat and Grb10 showed instances of differential or abnormal expression in SCNT embryos. The chromatin remodeling genes were maintained in all SCNT treatments. Prkcsh and Sec63 were both absent in one HMC blastocyst, with implications for liver dysfunction, a condition previously reported in abnormal cloned offspring. The variable mRNA expression following SCNT provides an insight into genetic and environmental factors controlling implantation, placentation, organ formation, and fetal growth.

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