RESUMO
Genomic imprinting is an important epigenetic mechanism that has vital effects on fetal growth and development. We observed the differences in four tissues (heart, spleen, liver, and kidney) from dead transgenic cloned goats using hematoxylin and eosin (H&E) staining. Eight imprinted genes in the tissues of dead transgenic cloned and normal goats were analyzed using reverse transcription polymerase chain reaction. H&E staining results from the abortion group indicated the lack of obvious morphological changes in heart and spleen tissues, while inflammatory cell infiltration and glomerular nephritis characteristics were observed in liver and kidney tissues, respectively. Compared to the control group, CDKN1C, H19, IGF2R, and SNRPN were significantly (P < 0.05) overexpressed in the heart tissue of the abortion group, while XIST was significantly reduced. In the liver tissues, CDKN1C and DLK1 expression decreased, while GNAS, H19, IGF2R, PEG3, and XIST expression increased significantly. In the spleen tissues, DLK1 expression increased, while GNAS, H19, IGF2R, PEG3, SNRPN, and XIST expression decreased. In the kidney tissues, CDKN1C, DLK1, GNAS, IGF2R, and PEG3 expression increased, while H19 and XIST expression decreased. The overall expression of imprinted genes was abnormal in different tissues of transgenic cloned goats, and the degree of abnormal genomic imprinting was more severe in the abortion group compared to the death and control groups. These results suggest that abnormal expression of imprinted genes may cause developmental defects in transgenic cloned goats. Moreover, abnormal epigenetic modifications may affect the reprogramming of transgenic donor cells.
Assuntos
Clonagem de Organismos/mortalidade , Epigênese Genética , Genes Letais , Impressão Genômica , Cabras/genética , Lactoferrina/genética , Animais , Animais Geneticamente Modificados , Inibidor de Quinase Dependente de Ciclina p57/genética , Inibidor de Quinase Dependente de Ciclina p57/metabolismo , Feminino , Perfilação da Expressão Gênica , Cabras/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Rim/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Lactoferrina/metabolismo , Fígado/metabolismo , Masculino , Miocárdio/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Gravidez , Transdução de Sinais , Baço/metabolismo , TransgenesRESUMO
We investigated the expression and distribution of N-cadherin during the development of a rat heart. Immunohistochemistry (IHC) was performed to detect the expression and distribution of N-cadherin in the myocardial tissues of rats at embryonic day 18 (E18d), postnatal day 5 (P5d), postnatal day 19 (P19d), postnatal day 40 (P40d), and postnatal year 1 (P1y). Reverse transcription polymerase chain reaction was used to determine mRNA expression levels of N-cadherin in the myocardial tissues at E18d, P5d, P19d, P40d, and P1y. The IHC results showed that at E18d N-cadherin was dispersedly distributed both on the cell surface and in the cytoplasm of the myocardial cells, and gradually became concentrated at the end-to-end intercalated discs of the cardiomyocytes from birth through immaturity. In the young, middle-aged, and old rats, N-cadherin was typically distributed at the intercalated discs at the end of the myocardial cells. No significant differences in the mRNA expression levels of N-cadherin were detected in the myocardial tissue of rats at E18d, P5d, P19d, P40d, and P1y. During the development of the rat heart, observable changes in the distribution of N-cadherin occurred in the myocardial tissues, but there were no detectable changes in the expression of N-cadherin, indicating that N-cadherin is indispensable to maintaining the physical structure and function of the heart.
Assuntos
Caderinas/genética , Regulação da Expressão Gênica no Desenvolvimento , Coração/embriologia , Miocárdio/metabolismo , Animais , Feminino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RatosRESUMO
Dairy goat is a good model for production of transgenic proteins in milk using somatic cell nuclear transfer (SCNT). However, animals produced from SCNT are often associated with lung deficiencies. We recently produced six transgenic cloned dairy goats harboring the human lactoferrin gene, including three live transgenic clones and three deceased transgenic clones that died from respiratory failure during the perinatal period. Imprinted genes are important regulators of lung growth, and may be subjected to faulty reprogramming. In the present study, first, microsatellite analysis, PCR, and DNA sequence identification were conducted to confirm that these three dead kids were genetically identical to the transgenic donor cells. Second, the CpG island methylation profile of the imprinted insulin-like growth factor receptor (IGF2R) gene was assessed in the lungs of the three dead transgenic kids and the normally produced kids using bisulfite sequencing PCR. In addition, the relative mRNA level of IGF2R was also determined by real-time PCR. Results showed that the IGF2R gene in the lungs of the dead cloned kids showed abnormal hypermethylation and higher mRNA expression levels than the control, indicating that aberrant DNA methylation reprogramming is one of the important factors in the death of transgenic cloned animals.
Assuntos
Cabras/genética , Lactoferrina/genética , Pulmão/metabolismo , Receptor IGF Tipo 2/genética , Animais , Animais Geneticamente Modificados , Sequência de Bases , Clonagem de Organismos , Metilação de DNA , Transferência Embrionária , Feminino , Expressão Gênica , Impressão Genômica , Humanos , Repetições de Microssatélites , Dados de Sequência Molecular , Receptor IGF Tipo 2/metabolismo , Análise de Sequência de DNARESUMO
The enhanced green fluorescent protein (EGFP) pEGFP-N1-P53 eukaryotic expression vector, which contains the human tumor suppressor p53, was constructed and transfected into chicken fibroblast cells and stage-X blastoderm to analyze the transfection efficiency. The complementary DNA of the human p53 gene was cloned by reverse transcription-polymerase chain reaction from human peripheral blood and inserted into the pEGFP-N1 vector by HindIII and BamHI double digestion. The pEGFP-N1-P53 vector was transfected into chicken embryo fibroblasts by Lipofectamine 2000 liposomes, and the transfection efficiency was analyzed by fluorescence microscope after 36 h of transfection. The stage-X blastoderm was also transfected by blastoderm injection using Lipofectamine 2000 liposomes at room temperature after 12-24 h; then hatching occurred until seventh day, and the transfection efficiency was analyzed by fluorescence microscope in the dead embryo. A total of 90 hatching eggs were transfected by the pEGFP-N1-P53 vector, and 20 chicken embryos expressed the reporter gene, which indicated that recombinant pEGFP-N1-P53 could be transfected and expressed in stage-X blastoderm by liposomes. Chicken embryo fibroblasts were transfected and expressed the reporter gene. The pEGFP-N1-P53 vector was constructed successfully and could be transfected and expressed in chicken embryo fibroblasts and stage-X blastoderms efficiently.