小鼠遗传背景对4n胚胎及2n-4n聚合胚制作效率的影响

不同品系小鼠的 2 细胞期胚胎 (二倍体 ,2n) ,经电融合后 ,获得发育的 4 细胞期四倍体胚胎 (4n)的能力上存在着差异。将不同品系小鼠的 2n、 4n胚胎分别配对作聚合 ,所获 2n 4n聚合胚的发育结果表明 :在着床前 ,2n 4n聚合胚的获得率因胚胎品系组合的不同而异 ;胚胎移植后 ,聚合胚在与 4n胚胎相同或相近品系的移植受体中 ,其着床率较高 ;在着床后胎儿及出生仔鼠的获得率上 ,采用遗传杂合性的 2n胚胎所组成的 2n 4n聚合组合较高。上述结果提示 :小鼠的遗传背景可影响到 4n胚胎及相应 2n 4n聚合胚的制作效率。以GFP标记跟踪2n 4n聚合胚 4n细胞着床后的发育命运 ,发现 :妊娠中后期的孕体中 ,4n细胞限制性地分布至胚外组织

Influence of mouse genetic background on the production efficiency of tetraploid embryo and diplid-tetraploid aggregate

Developmental capacities of mouse tetraploid (4n) embryos at the 4-cell stage varies among mice species after electrofusing diploid blastomeres at the 2-cell stage. Further study on developmental capacities of diploid-tetraploid (2n-4n) aggregates made by 2n and 4n embryo with different combinations in mice species showed that: acquistion efficiency of preimplanted 2n-4n aggregates differed in various embryos recombinations involved;the implantation ratio for 2n-4n aggregates could be higher when transferred to recipient mice the same as or similar to the tetraploid embro; developmental ratio of mid-late gestated fetus or mice from 2n-4n aggregates seemed higher for genetically hybrid 2n embryos adopted for aggregation. The results demonstrate that the genetic backgroud of mouse has some effect on the production efficiency both for 4n embryo and for 2n-4n aggregates. Following the developmental fate of 4n cells in 2n-4n aggregates with GFP marker, we found its restrictive allocation in extraembryonic tissues in the postimplanted conceptus