scholarly journals 317 FACTORS AFFECTING PRODUCTION EFFICIENCY OF TRANSGENIC RATS BY ICSI-MEDIATED DNA TRANSFER

2005 ◽  
Vol 17 (2) ◽  
pp. 309
Author(s):  
M. Kato ◽  
S. Hochi ◽  
M. Hirabayashi
Keyword(s):  
Production Efficiency ◽  
Dna Transfer ◽  
Egfp Expression ◽  
Transgenic Rat ◽  
Sprague Dawley ◽  
Transgenic Rats ◽  
Rat Strains ◽  
Exogenous Dna ◽  
Factors Affecting ◽  
Rat Offspring

Successful DNA transfer via intracytoplasmic sperm injection (ICSI) was first reported in mice (Perry et al. 1999, Science 284, 1180), and was recently extended to rats (Kato et al. 2004, Mol. Reprod. Dev. 69, 153). In the present study, factors affecting the production efficiency of transgenic rats by the ICSI-mediated DNA transfer were investigated. Cauda epididymal spermatozoa from Sprague-Dawley rats were sonicated (SO) and/or frozen-thawed (FT) for tail-cutting and membrane-disrupting. The sperm heads were exposed for 1 min to different concentrations (0.02–2.5 ng/μL) of 3.0 kb EGFP DNA solution, and then microinjected into denuded F1 (Donryu × LEW) rat oocytes. The optimal concentration of EGFP DNA was 0.1 ng/μL, as determined by the in vitro developmental competence into morulae/blastocysts and the EGFP expression of the ICSI oocytes. The presumptive 1- or 2-cell stage zygotes were transferred into oviducts of pseudopregnant Wistar females, and the presence of EGFP DNA in the offspring was examined by fluorescence under the 480 nm UV light. The production efficiency of transgenic rat offspring was 2.8% (2/71 zygotes transferred), 1.6% (1/63), and 3.3% (2/61) in the oocytes into which SO-, FT-, and SO+ FT-treated sperm heads were injected, respectively. The founder transgenic rats carrying EGFP DNA transmitted the transgenes to their progeny according to the Mendelian fashion (43.8–54.8%), suggesting the stable incorporation of the transgenes into rat genomes. Four rat strains (F344, LEW, Donryu, and Sprague-Dawley) were compared for their suitability as sperm/oocyte donors in the production of transgenic rats by ICSI with SO + FT-treated and 0.1 ng/μL EGFP DNA-exposed sperm heads. The production efficiency of the transgenic rats in the Sprague-Dawley strain (8.2%, 8/98) was significantly higher than that in LEW strain (0.9%, 1/114), while those in F344 (4.3%, 4/92) and Donryu (4.4%, 5/114) strains were intermediate. Attempts were made to introduce three other DNA constructs (5.0 kb plasmid and 208 kb BAC, both with Fyn gene, and 186 kb BAC with Svet1/IRES-Cre gene) into rat genomes by ICSI with SO + FT-treated and 0.1 ng/μL DNA-exposed sperm heads. PCR analysis showed that the Fyn, Fyn/BAC, and Svet1/IRES-Cre DNA constructs were successfully introduced into Sprague-Dawley rat offspring via ICSI, with production efficiencies of 2.8% (3/109), 0.9% (1/109), and 2.4% (3/125), respectively. These results indicate that transgenic rats can be produced by ICSI-mediated DNA transfer using the various types of exogenous DNA and rat strains with different genetic backgrounds.

Efficient transgenic rat production by a lentiviral vector

2007 ◽  
Vol 293 (1) ◽  
pp. H881-H894 ◽  
Author(s):  
Mieczyslaw Michalkiewicz ◽  
Teresa Michalkiewicz ◽  
Aron M. Geurts ◽  
Richard J. Roman ◽  
Glenn R. Slocum ◽  
...  
Keyword(s):  
Fluorescent Protein ◽  
Lentiviral Vector ◽  
Insertion Site ◽  
Single Copy ◽  
Egfp Expression ◽  
Transgenic Rat ◽  
Sprague Dawley ◽  
Lentiviral Transgenesis ◽  
Sprague Dawley Rats ◽  
Transgenic Lines

A lentiviral construct for an enhanced green fluorescent protein (eGFP) driven by a chicken β-actin promoter, cytomegalovirus enhancer, and intronic sequences from rabbit β-globin (CAG) was used to produce transgenic lines of rats for evaluation of the usefulness of this approach in gene function studies. Fertilized eggs were collected from inbred Dahl S and outbred Sprague-Dawley rats, and ∼100 pl of concentrated virus were microinjected into the perivitrelline space of one-cell embryos. Of 121 embryos injected, 60 pups (49.6%) were born. Transgenic rates averaged 22% in Dahl S and 14% in Sprague-Dawley rats. Copy number ranged from one to four in the founders, and the inheritance of the transgene in a subsequent F1population was 48.2%. The small number of insertion sites enabled us to derive inbred transgenic lines with a single copy of the transgene within one generation. Sequencing of each transgene insertion site revealed that they inserted as single copies with a preference for the introns of genes. The CAG promoter drove high levels of eGFP expression in brain, kidney, heart, and vasculature, making it very suitable for exploring the cardiovascular function of newly discovered genes. The pattern of eGFP expression was similar across five different F1transgenic lines, indicating that the expression of the transgene was independent of its chromosomal position. Thus lentiviral transgenesis provides a powerful tool for the production of transgenic inbred rats and will enhance the usefulness of this species in gene discovery and target validation studies.

scholarly journals No Effect of Recombinase-Mediated DNA Transfer on Production Efficiency of Transgenic Rats

2006 ◽  
Vol 55 (2) ◽  
pp. 131-135 ◽  
Author(s):  
Masumi HIRABAYASHI ◽  
Megumi KATO ◽  
Ryosuke KANEKO ◽  
Takahiro HIRABAYASHI ◽  
Mitsuhiro MORITA ◽  
...  
Keyword(s):  
Production Efficiency ◽  
Dna Transfer ◽  
Transgenic Rats

scholarly journals THE Ah PHENOTYPE. SURVEY OF FORTY-EIGHT RAT STRAINS AND TWENTY INBRED MOUSE STRAINS

Genetics ◽  
1982 ◽  
Vol 100 (1) ◽  
pp. 79-87
Author(s):  
Daniel W Nebert ◽  
Nancy M Jensen ◽  
Hisashi Shinozuka ◽  
Heinz W Kunz ◽  
Thomas J Gill
Keyword(s):  
Specific Activity ◽  
Inbred Mouse ◽  
Inbred Mouse Strain ◽  
Mouse Strains ◽  
Ah Receptor ◽  
Inbred Mouse Strains ◽  
Sprague Dawley ◽  
Rat Strains ◽  
Specific Activities ◽  
Inbred Rat

ABSTRACT Forty-four inbred and four randombred rat strains and 20 inbred mouse strains were examined for their Ah phenotype by determining the induction of liver microsomal aryl hydrocarbon (benzo[a]pyrene) hydroxylase activity (EC 1.14.14.1) by intraperitoneal treatment with either β-naphthoflavone or 3-methylcholanthrene. All 48 rat strains were found to be Ah-responsive. The maximally induced hydroxylase specific activities of the ALB/Pit, MNR/Pit, MR/Pit, SHR/Pit, and Sprague-Dawley strains were of the same order of magnitude as the basal hydroxylase specific activities of the ACI/Pit, F344/Pit, OKA/Pit, and MNR/N strains. Six of the 20 mouse strains were Ah-nonresponsive (i.e. lacking the normal induction response and presumably lacking detectable amounts of the Ah receptor). The basal hydroxylase specific activities of the BDL/N, NFS/N, STAR/N, and ST/JN mouse strains were more than twice as high as the maximally induced hydroxylase specific activity of the CBA/HT strain.——To date, 24 Ah-nonresponsive mouse strains have been identified, out of a total of 68 known to have been characterized. The reasons for not finding a single Ah-nonresponsive inbred rat strain—as compared with about one Ah-nonresponsive inbred mouse strain found for every three examined—remain unknown.

scholarly journals Estrogen Receptor α Gene Promoter 0/B Usage in the Rat Sexually Dimorphic Nucleus of the Preoptic Area

Endocrinology ◽  
2010 ◽  
Vol 151 (4) ◽  
pp. 1923-1928 ◽  
Author(s):  
Tomohiro Hamada ◽  
Yasuo Sakuma
Keyword(s):  
Estrogen Receptor ◽  
Sexual Differentiation ◽  
Preoptic Area ◽  
Gene Promoter ◽  
Estrogen Receptor Α ◽  
Egfp Expression ◽  
Sexually Dimorphic ◽  
Transgenic Rats ◽  
The Core ◽  
Sexually Dimorphic Nucleus

The volume of the sexually dimorphic nucleus of the preoptic area (SDN-POA) is two to four times larger in male rats than in females; however, the mechanism for the establishment of sexual dimorphism and the function of this nucleus is almost unknown. Perinatal estrogen can cause sexual dimorphism via the estrogen receptor α (ERα). Recently, transgenic rats were generated that express enhanced green fluorescent protein (EGFP) under the control of the ERα gene promoter 0/B to tag ERα-positive neurons in the brain. In the present study, we examined whether this EGFP expression could be a marker for the SDN-POA in adults. EGFP-labeled cells were distributed in the core of the SDN-POA (0/B-SDN) of male and female transgenic rats, in accordance with the Nissl staining and immunoreactivity for the SDN marker, calbindin. They were also immunoreactive for ERα. The core was bigger in volume and contained more 0/B-SDN neurons in males than in females. The EGFP-tagged cells were packed more densely in the female core than that in males. Subcutaneous injection of 100 μg 17β-estradiol to females on the day of birth, or orchidectomy of male neonates, reversed the sexually dimorphic phenotype of the volume of the 0/B-SDN, despite not affecting the cell number. We suggest that this EGFP expression in the SDN-POA could be a useful marker to clarify the sexual differentiation and function of the SDN-POA. Moreover, the ERα gene promoter 0/B plays a key role in the organization of the sexual differentiation of the SDN-POA.

Mechanisms of hypertension in transgenic rats expressing the mouse Ren-2 gene

1994 ◽  
Vol 266 (4) ◽  
pp. R1273-R1279 ◽  
Author(s):  
A. Moriguchi ◽  
K. B. Brosnihan ◽  
H. Kumagai ◽  
D. Ganten ◽  
C. M. Ferrario
Keyword(s):  
Mature Female ◽  
Response To Therapy ◽  
Ang Ii ◽  
Sprague Dawley ◽  
Transgenic Rats ◽  
Contrast Administration ◽  
Systemic Injection ◽  
Endothelin 1 ◽  
Sd Rats ◽  
Insight Into

Transgenic (TG) rats carrying the mouse Ren-2 gene (Ren-2d)27 are a newly established monogenetic model in hypertension research. To gain an insight into the mechanisms of this form of hypertension we determined the effects of a 13-day therapy with losartan (10 mg/kg) or lisinopril (20 mg/kg) on the blood pressure (BP) and plasma levels of angiotensin (ANG) peptides of mature female TG hypertensive and Sprague-Dawley (SD) rats. The contribution of endothelium-derived nitric oxide (NO) to the maintenance of their hypertension and the response to therapy was evaluated by systemic injection of either NG-monomethyl-L-arginine (L-NMMA) or endothelin-1. Hypertension in TG rats was associated with decreased plasma ANG I, no differences in plasma ANG II, and plasma ANG-(1-7) near the detectable level. Lisinopril lowered BP more than losartan in both TG hypertensive and normotensive controls. In both strains, the chronic fall in BP produced by lisinopril was accompanied by significant increases in plasma ANG I and ANG-(1-7), while losartan augmented plasma ANG I and ANG II in both strains and plasma ANG-(1-7) in TG rats. Inhibition of NO synthase reversed the fall in BP produced by either lisinopril or losartan in SD controls. In contrast, administration of L-NMMA to TG rats given the same therapy did not. The transient endothelium-mediated relaxing phase of the depressor response to systemic injections of endothelin-1 was attenuated by losartan and lisinopril in TG rats. These studies indicate that hypertension in female TG rats is mediated by the RAS.(ABSTRACT TRUNCATED AT 250 WORDS)

Hypertensive retinopathy in a transgenic angiotensin-based model

2016 ◽  
Vol 130 (13) ◽  
pp. 1075-1088 ◽  
Author(s):  
Nadine Reichhart ◽  
Nadine Haase ◽  
Sergio Crespo-Garcia ◽  
Sergej Skosyrski ◽  
Christina Herrspiegel ◽  
...  
Keyword(s):  
Gene Expression ◽  
Ganglion Cells ◽  
Renin Angiotensin System ◽  
Retinal Disease ◽  
Fluorescence Angiography ◽  
Peripheral Retina ◽  
Transgenic Rat ◽  
Hypertensive Retinopathy ◽  
Sprague Dawley ◽  
Blood Retinal Barrier

Severe hypertension destroys eyesight. The RAS (renin–angiotensin system) may contribute to this. This study relied on an established angiotensin, AngII (angiotensin II)-elevated dTGR (double-transgenic rat) model and same-background SD (Sprague–Dawley) rat controls. In dTGRs, plasma levels of AngII were increased. We determined the general retinal phenotype and observed degeneration of ganglion cells that we defined as vascular degeneration. We also inspected relevant gene expression and lastly observed alterations in the outer blood–retinal barrier. We found that both scotopic a-wave and b-wave as well as oscillatory potential amplitude were significantly decreased in dTGRs, compared with SD rat controls. However, the b/a-wave ratio remained unchanged. Fluorescence angiography of the peripheral retina indicated that exudates, or fluorescein leakage, from peripheral vessels were increased in dTGRs compared with controls. Immunohistological analysis of blood vessels in retina whole-mount preparations showed structural alterations in the retina of dTGRs. We then determined the general retinal phenotype. We observed the degeneration of ganglion cells, defined vascular degenerations and finally found differential expression of RAS-related genes and angiogenic genes. We found the expression of both human angiotensinogen and human renin in the hypertensive retina. Although the renin gene expression was not altered, the AngII levels in the retina were increased 4-fold in the dTGR retina compared with that in SD rats, a finding with mechanistic implications. We suggest that alterations in the outer blood–retinal barrier could foster an area of visual-related research based on our findings. Finally, we introduce the dTGR model of retinal disease.

335 CYTOPLASMIC MICROINJECTION OF EXOGENOUS DNA IN IN VITRO AND IN VIVO DERIVED SHEEP EMBRYOS

2011 ◽  
Vol 23 (1) ◽  
pp. 263
Author(s):  
F. Pereyra-Bonnet ◽  
A. Gibbons ◽  
M. Cueto ◽  
R. Bevacqua ◽  
L. Escobar ◽  
...  
Keyword(s):  
Fluorescent Protein ◽  
Genetically Modified ◽  
Fold Increase ◽  
Egfp Expression ◽  
Control Group ◽  
Corpora Lutea ◽  
Exogenous Dna ◽  
Frozen Semen

Microinjection of DNA into the male pronucleus is a commonly used method to generate transgenic animals. However, it is only moderately efficient in several species because it requires proper male pronuclear visualisation, which occurs only in a narrow window of time in mice. The cytoplasmic microinjection of exogenous DNA (eDNA) is an alternative method that has not been fully investigated. Our objective was to evaluate if cytoplasmic microinjection of eDNA is capable of producing genetically modified embryos. In vitro and in vivo derived sheep embryos were cytoplasmically microinjected with pCX-EGFP previously incubated (5 min in a PVP droplet) with oolemma-cytoplasm fragments obtained from donor oocytes by microsurgery. A control group using microinjected plasmid alone was included in the in vivo procedure. For in vitro microinjection, IVF embryos were microinjected with circular plasmid with promoter (50 or 500 ng μL–1) or without promoter (50 ng μL–1) at 6 h after fertilization. The IVF was performed following (Brackett and Olliphant 1975 Biol. Reprod. 12, 260–274) with 15 × 106 spermatozoa mL–1, and presumptive zygotes were cultured in SOF. The expression of enhance green fluorescent protein (EGFP) was determined under blue light. For in vivo microinjection, embryos from superovulated sheep (by standard procedures) were recovered and microinjected with 50 ng μL–1 of linearized plasmid without promoter at 12 h after laparoscopic insemination with frozen semen (100 × 106 spermatozoa per sheep). Plasmid without promoter was used to avoid any possible cytotoxic effect produced by EGFP expression. The microinjection of IVF embryos with 50 ng μL–1 of plasmid was the best condition to produce embryos expressing eDNA (n = 96; 46.9% cleaved; 12.2% blastocysts; 53.0 and 4.1% of green embryos and blastocysts, respectively). Variables between the groups with or without promoter IVF were not statistically different (Fisher test: P < 0.05); however, when 500 ng μL–1 was microinjected, no blastocysts were obtained. In the in vivo embryo production group, 111 presumptive zygotes were microinjected (n = 37; with plasmid alone) from 16 donor sheep (11.5 ± 4.0 corpora lutea; 8.4 ± 4.8 presumptive zygotes recovered; 74.3% recovery rate). The mean time from injection to cleavage was 18.0 ± 4.5 h, and the percentage of cleavage and damage (due to the embryo injection) were >70% and <10%, respectively. Fifty-eight good quality embryos were transferred into the oviducts of 19 surrogate ewes; 12 of them are pregnant (63.1%). The presence of green IVF embryos demonstrates that eDNA was transported to the nucleus after cytoplasmic injection. We believe that the multi-fold increase (50- to 100-fold) in plasmid concentration compared with that used by others was the key step to our successful cytoplasmic microinjection. Accordingly, the new/old methodology described in this study provides an easy DNA construct delivery system of interest for the implementation of early reprogramming events. In addition, results obtained in the near future using in vivo cytoplasmic microinjection with high concentrations of eDNA could revalidate this technique for producing genetically modified large animals.

240 QUALITY AND VIABILITY OF IVF BOVINE EMBRYOS AFTER INTRACYTOPLASMIC INJECTION OF DNA–LIPOSOME COMPLEXES

2012 ◽  
Vol 24 (1) ◽  
pp. 232
Author(s):  
L. N. Moro ◽  
G. Vichera ◽  
D. Salamone
Keyword(s):  
In Vitro Culture ◽  
Dna Fragmentation ◽  
Transgene Expression ◽  
Fluorescent Protein ◽  
Transgenic Animals ◽  
Egfp Expression ◽  
Bovine Embryos ◽  
Exogenous Dna ◽  
Intracytoplasmic Injection

Transgenic animals have important applications in agriculture and human medicine; nevertheless the available techniques still remain inefficient and technically difficult. We have recently developed a novel method to transfect bovine embryos that consists of intracytoplasmic injection of exogenous DNA–liposome complexes (eDNA-LC) in IVF zygotes. This study was designed to evaluate the quality and viability of IVF bovine embryos, after intracytoplasmic injection of pCX-EGFP–liposome complexes (EGFP-LC) or pBCKIP2.8-liposome complexes (plasmid that codifies the human insulin gene, HI-LC). First, we evaluated embryo development and enhanced green fluorescent protein (EGFP) expression of IVF embryos injected with both plasmids separately. This treatment was analysed by Fisher's Exact test (P ≤ 0.05). Cleavage rates for EGFP-LC, HI-LC and IVF embryos injected with liposomes alone (IVF-L) and IVF control (IVF-C) were 62% (63/102), 67% (67/100), 66% (67/101) and 79% (98/124); blastocysts rates were 17% (17/102), 21% (21/100), 21% (21/101) and 23% (28/124), respectively. No statistical differences were seen among groups. The percentage of EGFP-positive embryos (EGFP+) after EGFP-LC injection was 42.9% after 3 days of culture and 41.8% at the blastocyst stage. In the second experiment, the blastocysts obtained, EGFP+ or EGFP-negative (EGFP–), were analysed by TUNEL assay at Day 6 (Bd6), 7 (Bd7) and 8 (Bd8) of in vitro culture, in order to evaluate the effect of the transgene and culture length, on DNA fragmentation. This treatment was analysed by the difference of proportions test (P ≤ 0.05) using statistical INFOSTAT software. All EGFP+ blastocysts showed TUNEL positive cells (T+). The percentage of T+ in Bd6, Bd7 and Bd8 were 91, 73.7 and 99.5%, respectively (P ≤ 0.05). EGFP– blastocysts showed lower fragmented nuclei (0, 44.6 and 85%, respectively; P ≤ 0.05). Groups IVF-L and IVF-C were also evaluated. In both groups, there was no evidence of DNA fragmentation in Bd6 and Bd7, but T+ were detected in Bd8 (66.4 and 85.8%, respectively; P ≤ 0.05). In the third experiment, bovine blastocysts obtained from the HI-LC group were individually transferred to recipient cows after 6 (n = 11), 7 (n = 5) and 8 (n = 5) days of culture post-IVF and HI-LC injection. The pregnancies obtained were from Bd6 [18.2% (2/11)] and Bd7 [40% (2/5)], although none of the recipients receiving Bd8 were diagnosed pregnant. Two pregnancies developed to term, one derived from Bd6 and the other from Bd7. Analysis by PCR determined that none of the born cows were transgenic. In summary, IVF bovine embryos could be easily transfected after the injection of eDNA-LC and the technique did not affect offspring viability. The results indicate that extended time in in vitro culture increases the percentage of fragmented nuclei in blastocysts. Moreover, this parameter increases in blastocysts with transgene expression compared with those without expression. Finally, more transfers are required in order to obtain the real efficiency of this new technique and to overcome the drawbacks generated by in vitro culture length and transgene expression.

94 Myostatin gene editing by CRISPR/Cas9 technology of Brangus fetal fibroblasts to produce edited embryos by cloning

2021 ◽  
Vol 33 (2) ◽  
pp. 154
Author(s):  
J. I. Bastón ◽  
D. Viale ◽  
M. Olguin ◽  
E. Wiedenmann ◽  
V. Arnold ◽  
...  
Keyword(s):  
Gene Expression ◽  
Production Efficiency ◽  
Gene Editing ◽  
Premature Stop Codon ◽  
Exogenous Dna ◽  
Exon 2 ◽  
Myostatin Gene ◽  
Mstn Gene ◽  
Cattle Breeds ◽  
Fetal Fibroblasts

Some European cattle breeds, such as Charolais and Maine Anjou, have natural mutations in the myostatin gene (MSTN) that inhibit its expression and result in an increase in muscle mass and protein content. An innovative hallmark would be the invitro introduction of this genotype in South America cattle breeds to improve their commercial value. To achieve this, we aimed to disrupt MSTN gene expression in bovine fetal fibroblasts (BFFs) using CRISPR/Cas9 technology and to generate MSTN-edited embryos by somatic cell nuclear transfer (SCNT). BFFs were isolated from a cloned fetus of a Brangus bull with a prized genetic background and nucleofected with the Cas9 ribonucleoprotein-gRNA complex previously assessed to target exon 2 of the bovine MSTN gene. To evaluate MSTN editing, genomic DNA from the wild-type (WT) and nucleofected BFFs were isolated, exon 2 of MSTN was amplified by PCR, and the PCR product was Sanger sequenced. In all cases, the sequencing results were analysed using the indel Synthego software tool. According to indel analysis, MSTN gene editing efficiency of the BFFs was 58.83%±3.2 (n=6). The resulting edit consisted of insertion of thymine in exon 2 of the MSTN gene that shifted the gene reading frame, introducing a premature stop codon and generating a truncated MSTN protein. The nucleofected BFFs were then used to generate embryos by SCNT, and WT BFFs were included as controls. Embryo cleavage and blastocyst development rates were evaluated at Day 2 and 7, respectively (Chi-squared test, P&lt;0.05). Although lower cleavage rates were obtained in the MSTN-edited BFFs group [65.3% (n=273/418) vs. 87.6% (n=169/193)], no differences were observed at the blastocyst stage [19.1% (n=80/418) vs. 25.4% (n=49/193)]. To confirm the efficiency of MSTN editing in the cloned embryos, 10 blastocysts generated with the MSTN-edited BFFs were individually analysed for MSTN exon 2 sequence as described before. The results showed that 30% of the blastocysts (3/10) presented a homozygous biallelic edition, which consisted of a thymine base insertion, as expected. In summary, the strategy we used allowed production of MSTN null cloned Brangus embryos avoiding putative undesired integration of exogenous DNA into the bovine genome, such as plasmid sequence, regardless of off-target occurrences. We conclude that CRISPR/Cas9 is an efficient technique to disrupts MSTN gene expression in bovine embryos; this work represents a step toward improving the production efficiency of South American cattle breeds.

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