Molecular mechanism and physiological meaning of genomic imprinting in mouse stem cell.

Genomic imprinting is monoallelically expressed genes in a parent-of-origin dependent manner. Genomic imprinting play roles in the growth and homeostasis of in mammal. Therefore, aberrant activation of imprinted genes lead to severe defects in the development and growth. However, activation of silenced allele of imprinted genes is generally observed during the establishment of mouse embryonic stem cells. Similarly, loss-of-imprinting phenomenon was observed in H3K27me3-dependent imprinting in ICM differentiation. The purpose of current experiment is to reveal the underlying mechanism and biological meaning of these loss-of-imprinting in stem cell population through the expression analysis of pre-implantation embryos and cultured embryos at single cell level.