In the traditional views on developmental biology, the process of a mammal from a zygote to. an adult individual follows continuous changes of space and time environments and is the result of different expressions of ...In the traditional views on developmental biology, the process of a mammal from a zygote to. an adult individual follows continuous changes of space and time environments and is the result of different expressions of target genes. It has long been known that this process is irreversible and the terminal differentiated adult cells, such as cardiac myocytes and neurons, will not divide and differentiate. But recent reports on the two hottest fields - cloning medicine and stem cell biology doubted these concepts. This may lead to a further understanding of the potentiality of mammal development and may provide great chances for commercial and clinical practice.展开更多
The developmental competence of porcine parthenotes cultured in porcine zygote medium-3 （PZM-3） and North Carolina State University-23 （NCSU-23） media was investigated. After in vitro maturation oocytes were elect...The developmental competence of porcine parthenotes cultured in porcine zygote medium-3 （PZM-3） and North Carolina State University-23 （NCSU-23） media was investigated. After in vitro maturation oocytes were electro-activated, and the subsequent developmental competence, rates of apoptotic, fragmented and arrested embryos from the two media were evaluated. Also, the ratio of mRNA expression of Bcl-2 and Bax gene was determined. Results demonstrated that cleavage, blastocyst, hatched blastocyst rates, and blastocyst cell numbers were significantly higher in PZM-3 than in NCSU-23. The rate of fragmented embryos in PZM-3 was lower than in NCSU-23 on d 1 and 3 （P〈0.05） while the percentage of arrested embryo was lower in PZM-3 than in NCSU-23 on d 4 and 5 （P〈0.05）. TUNEL positive signals were higher in NCSU-23 than in PZM-3 from d 3 to 7 （P〈0.05）. The ratios of Bcl-2 and Bax mRNA expression in embryos were higher on d 5 than on d 3 and 1 in PZM-3 （P〈0.05）. In contrast, the ratios of Bcl-2 and Bax mRNA expression in embryos on d 1 were higher than on d 3 and 5 in NCSU-23 （P〈0.05）. Additionally, the ratios of Bcl-2 and Bax mRNA expression in embryos in PZM-3 were higher than in NCSU-23 on d 3 and 5 （P〈0.05）. In conclusion, lower apoptotic embryo rates and down-regulating Bax together with up-regulating expression of Bcl-2 transcripts may be responsible for the better developmental competence of porcine parthenotes in PZM-3.展开更多
基金This work was supported by the "973" Project (Grant No. G1999054205).
文摘In the traditional views on developmental biology, the process of a mammal from a zygote to. an adult individual follows continuous changes of space and time environments and is the result of different expressions of target genes. It has long been known that this process is irreversible and the terminal differentiated adult cells, such as cardiac myocytes and neurons, will not divide and differentiate. But recent reports on the two hottest fields - cloning medicine and stem cell biology doubted these concepts. This may lead to a further understanding of the potentiality of mammal development and may provide great chances for commercial and clinical practice.
基金funded by the National Natural Science Foundation of China (31072031)the Key Research Program of Ministry of Education of China(109018)
文摘The developmental competence of porcine parthenotes cultured in porcine zygote medium-3 （PZM-3） and North Carolina State University-23 （NCSU-23） media was investigated. After in vitro maturation oocytes were electro-activated, and the subsequent developmental competence, rates of apoptotic, fragmented and arrested embryos from the two media were evaluated. Also, the ratio of mRNA expression of Bcl-2 and Bax gene was determined. Results demonstrated that cleavage, blastocyst, hatched blastocyst rates, and blastocyst cell numbers were significantly higher in PZM-3 than in NCSU-23. The rate of fragmented embryos in PZM-3 was lower than in NCSU-23 on d 1 and 3 （P〈0.05） while the percentage of arrested embryo was lower in PZM-3 than in NCSU-23 on d 4 and 5 （P〈0.05）. TUNEL positive signals were higher in NCSU-23 than in PZM-3 from d 3 to 7 （P〈0.05）. The ratios of Bcl-2 and Bax mRNA expression in embryos were higher on d 5 than on d 3 and 1 in PZM-3 （P〈0.05）. In contrast, the ratios of Bcl-2 and Bax mRNA expression in embryos on d 1 were higher than on d 3 and 5 in NCSU-23 （P〈0.05）. Additionally, the ratios of Bcl-2 and Bax mRNA expression in embryos in PZM-3 were higher than in NCSU-23 on d 3 and 5 （P〈0.05）. In conclusion, lower apoptotic embryo rates and down-regulating Bax together with up-regulating expression of Bcl-2 transcripts may be responsible for the better developmental competence of porcine parthenotes in PZM-3.
