Construction of cDNA Libraries from Single Mouse Preimplantation Embryos and Their Use of Specific Genes Detected During Development

Molecular analyses of early mammalian embryos are important and necessary for identifying the genes involved in normal development. Analysis of the genetic and molecular mechanisms of embryogenesis requires effective methods to find and isolate genes that are differentially expressed in normal and altered conditions.Construction of cDNA libraries from single mouse embryo and screen can lead to the discovery of known or novel transcripts that change in association with critical events. We report on the construction of cDNA libraries from single unfertilized oocyte, fertilized oocyte, two cell, four cell and eight cell stage embryos respectively. The complexities of these libraries are 6.2×10~(5)、8.3×10~(5)、1.04×10~(6)、1.51×10~(6)和1.62×10~(6) respectively. A total of 29 clones were picked and sequenced, 65.52%(19/29)to expressed sequence tags(ESTs) of mouse origin.Novel sequence were detected at a frequency of 13.79%(4/29) and found two repeat sequences in cDNA library from single four cell embryo.