title: Extensive contribution of embryonic stem cells to the development of an evolutionarily divergent host.
abstract: The full potential of embryonic stem (ES) cells to generate precise cell lineages and complex tissues can be best realized when they are differentiated in vivo-i.e. in developing blastocysts. Owing to various practical and ethical constraints, however, it is impossible to introduce ES cells of certain species into blastocysts of the same species. One solution is to introduce ES cells into blastocysts of a different species. However, it is not known whether ES cells can contribute extensively to chimerism when placed into blastocysts of a distantly related species. Here, we address this question using two divergent species, Apodemus sylvaticus and Mus musculus, whose genome sequence differs by approximately 18% from each other. Despite this considerable evolutionary distance, injection of Apodemus ES cells into Mus blastocysts led to viable chimeras bearing extensive Apodemus contributions to all major organs, including the germline, with Apodemus contribution reaching approximately 40% in some tissues. Immunostaining showed that Apodemus ES cells have differentiated into a wide range of cell types in the chimeras. Our results thus provide a proof of principle for the feasibility of differentiating ES cells into a wide range of cell types and perhaps even complex tissues by allowing them to develop in vivo in an evolutionarily divergent host-a strategy that may have important applications in research and therapy. Furthermore, our study demonstrates that mammalian evolution can proceed at two starkly contrasting levels: significant divergence in genome and proteome sequence, yet striking conservation in developmental programs.
authors.affiliation: Center for Stem Cell Biology and Tissue Engineering, Sun Yat-Sen University, Guangzhou 510080, China. xiangp@mail.sysu.edu.cn
authors.forename: Andy Peng
authors.initials: AP
authors.lastname: Xiang
authors.forename: Frank Fuxiang
authors.initials: FF
authors.lastname: Mao
authors.forename: Wei-Qiang
authors.initials: WQ
authors.lastname: Li
authors.forename: Donghyun
authors.initials: D
authors.lastname: Park
authors.forename: Bao-Feng
authors.initials: BF
authors.lastname: Ma
authors.forename: Tao
authors.initials: T
authors.lastname: Wang
authors.forename: Tammy W
authors.initials: TW
authors.lastname: Vallender
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Vallender
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.forename: Jaehyun
authors.initials: J
authors.lastname: Lee
authors.forename: John A
authors.initials: JA
authors.lastname: Waters
authors.forename: Xiu-Ming
authors.initials: XM
authors.lastname: Zhang
authors.forename: Xin-Bing
authors.initials: XB
authors.lastname: Yu
authors.forename: Shu-Nong
authors.initials: SN
authors.lastname: Li
authors.forename: Bruce T
authors.initials: BT
authors.lastname: Lahn
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D001483:Base Sequence; D005075:Biological Evolution; D001755:Blastocyst / Q000166:cytology; D002454:Cell Differentiation; D017931:DNA Primers / Q000235:genetics; D047108:Embryonic Development / Q000235:genetics; D053595:Embryonic Stem Cells / Q000166:cytology* / Q000637:transplantation; D005260:Female; D005854:Germ Cells; D049452:Green Fluorescent Proteins / Q000235:genetics; D008297:Male; D051379:Mice; D051189:Murinae / Q000196:embryology / Q000235:genetics; D009928:Organ Specificity; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D011994:Recombinant Proteins / Q000235:genetics; D013045:Species Specificity; D013724:Teratoma / Q000235:genetics / Q000473:pathology; D018183:Transplantation Chimera / Q000196:embryology / Q000235:genetics*; D014183:Transplantation, Heterologous
chemical_list: D017931:DNA Primers; D011994:Recombinant Proteins; D049452:Green Fluorescent Proteins