Pluripotent And Function Of Parthenogenetic Haploid Embryonic Stem Cells Of Mouse

Most organisms, including people, are diploid. There are two sets of chromosomes, one derived from the father and the other from the mother. However, the diploid is huge difficulty for genetic research, because it is hard to judge which set of chromosomes contribute the biological character and to reflect recessive gene phenotype when in the hybrid.While the haploid cells, such as streptococcus white and yeast is an important model of genetic research. There is only haploid gametes for mammal in natural state such as eggs and sperm both structure and function is specialized. To establish mammalian haploid cell lines in vitro will greatly promote the mammalian genetic, development, vevolution and related life science research. Researchers have built the haploid embryonic stem cells from medaka fish and they all only have a set of chromosomes. These new haploid stem cells can be used for fast analysis of gene regulatory network of mammalian development and for forward and reverse genetic screening and for building gene homozygous mutations library. The first mammals haploid embryonic stem cell lines has been established in2011, which greatly promote the progress of genetic studies. In2012, Our group and Li Jinsong’s group establish androgenetic haploid embryonic stem cell lines at the same time, and prove that these cells retain certain male imprint, even can produce healthy mice after replace the sperm injection to oocytes.In order to explore whether parthenogenetic haploid stem cell can also alternative eggs to support embryonic development, as androgenetic haploid stem cell can alternative sperm genome. This article discusses the pluripotent and functions of parthenogenetic haploid embryonic stem cells in mice for the first time. Using parthenogenetic activation builds haploid cell line and using flow cytometry sorting technology can maintain its haploid. Karyotype analysis and CGH hybrid technology was used to verify the haploid stem cell lines’ genome and gene copy number stability respectively. A stable GFP and RFP express and knockout parthenogenetic haploid embryonic stem cell lines can obtain by using PiggyBac expression technology and Cas9technology respectively, and the all extend the long-term stability.The parthenogenetic haploid are pluripotent. Immunofluorescence staining and rt-pcr analysis show pluripotent Marker express such as Oct4, Nanog, SOX2, Klf4and SSEA1. Genome-wide expression matrix show more similarity closer to diploid ES than MEF. Although all exists in diploidization, parthenogenetic haploid can also form teratoma with three layer differentiation and can chimeric to the internal organs of the mouse as the diploid ES do. Interestingly parthenogenetic haploid can also occur kinds of mosaic in genital gland and be able to pass on to the next generation.The Parthenogenetic haploid embryonic stem cells retain the mother imprinting, In spite of the low efficiency, it can support embryonic development maturity and generate viable healthy mice when inject into androgenetic embryos. This is first verify the parthenogenetic haploid embryonic stem cells to replace the maternal genome support embryonic development.