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Specification and epigenetic programming of the human germ line

Key Points

  • Regulation of pluripotency and early post-implantation embryonic development have diverged between humans and mice, which might affect the mechanism of primordial germ cell (PGC) specification.

  • Specification of human and mouse PGCs occurs in response to extrinsic signals, including bone morphogenetic protein 2 (BMP2) and BMP4.

  • Models of human PGC specification from pluripotent stem cells suggest that human PGCs originate from mesodermal precursors at the posterior epiblast during the onset of gastrulation, whereas mouse PGCs originate from the pre-gastrulation epiblast.

  • The gene regulatory network for PGC specification and maintenance in humans and mice has diverged. Notably, SRY-box 17 (SOX17), a key endoderm specifier, is critical for PGC specification in humans but not in mice.

  • PGCs undergo genome-wide DNA demethylation, which erases parental epigenetic memories and facilitates germ cell differentiation in humans and mice.

  • Repressive histone modifications might safeguard PGC genome stability during global DNA demethylation.

Abstract

Primordial germ cells (PGCs), the precursors of sperm and eggs, are established in perigastrulation-stage embryos in mammals. Signals from extra-embryonic tissues induce a unique gene regulatory network in germline-competent cells for PGC specification. This network also initiates comprehensive epigenome resetting, including global DNA demethylation and chromatin reorganization. Mouse germline development has been studied extensively, but the extent to which such knowledge applies to humans was unclear. Here, we review the latest advances in human PGC specification and epigenetic reprogramming. The overall developmental dynamics of human and mouse germline cells appear to be similar, but there are crucial mechanistic differences in PGC specification, reflecting divergence in the regulation of pluripotency and early development.

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Figure 1: Cycle of human germline development.
Figure 2: Signalling for mammalian germline induction.
Figure 3: Reconstitution of mouse and human PGC specification in vitro.
Figure 4: Gene regulatory network models for mouse and human PGC specification.
Figure 5: Epigenetic reprogramming in mouse and human PGCs.

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References

  1. Ohinata, Y. et al. A signaling principle for the specification of the germ cell lineage in mice. Cell 137, 571–584 (2009). A comprehensive signalling study that shows that BMP–phosphorylated SMAD (pSMAD) and WNT3 signalling pathways are indispensable for mPGC specification from the post-implantation epiblast during a restricted time window.

    CAS  PubMed  Google Scholar 

  2. Ohinata, Y. et al. Blimp1 is a critical determinant of the germ cell lineage in mice. Nature 436, 207–213 (2005).

    CAS  PubMed  Google Scholar 

  3. Yamaji, M. et al. Critical function of Prdm14 for the establishment of the germ cell lineage in mice. Nat. Genet. 40, 1016–1022 (2008). This paper shows that Prdm14 is crucial for the upregulation of pluripotency genes and the initiation of epigenetic reprogramming during mPGC specification.

    CAS  PubMed  Google Scholar 

  4. Weber, S. et al. Critical function of AP-2γ/TCFAP2C in mouse embryonic germ cell maintenance. Biol. Reprod. 82, 214–223 (2010). This article shows that Tfap2c , together with Prdm1 , represses mesodermal gene expression during mPGC specification.

    CAS  PubMed  Google Scholar 

  5. Magnusdottir, E. et al. A tripartite transcription factor network regulates primordial germ cell specification in mice. Nat. Cell Biol. 15, 905–915 (2013).

    CAS  PubMed  PubMed Central  Google Scholar 

  6. Magnusdottir, E. & Surani, M. A. How to make a primordial germ cell. Development 141, 245–252 (2014).

    CAS  PubMed  Google Scholar 

  7. Nakaki, F. et al. Induction of mouse germ-cell fate by transcription factors in vitro. Nature 501, 222–226 (2013). This study, along with reference 5, shows that overexpression of Prdm1, Tfap2c and/or Prdm14 is sufficient for the induction of mPGC fate.

    CAS  PubMed  Google Scholar 

  8. Lawson, K. A. & Hage, W. J. Clonal analysis of the origin of primordial germ cells in the mouse. Ciba Found. Symp. 182, 68–84; discussion 84–91 (1994).

    CAS  PubMed  Google Scholar 

  9. Seisenberger, S. et al. The dynamics of genome-wide DNA methylation reprogramming in mouse primordial germ cells. Mol. Cell 48, 849–862 (2012).

    CAS  PubMed  PubMed Central  Google Scholar 

  10. Hackett, J. A. et al. Germline DNA demethylation dynamics and imprint erasure through 5-hydroxymethylcytosine. Science 339, 448–452 (2013).

    CAS  PubMed  Google Scholar 

  11. Guibert, S., Forne, T. & Weber, M. Global profiling of DNA methylation erasure in mouse primordial germ cells. Genome Res. 22, 633–641 (2012). References 9–11 describe the detailed genome-wide DNA demethylation dynamics in mPGCs.

    CAS  PubMed  PubMed Central  Google Scholar 

  12. Hajkova, P. et al. Epigenetic reprogramming in mouse primordial germ cells. Mech. Dev. 117, 15–23 (2002).

    CAS  PubMed  Google Scholar 

  13. Lee, J. et al. Erasing genomic imprinting memory in mouse clone embryos produced from day 11.5 primordial germ cells. Development 129, 1807–1817 (2002).

    CAS  PubMed  Google Scholar 

  14. Sugimoto, M. & Abe, K. X chromosome reactivation initiates in nascent primordial germ cells in mice. PLoS Genet. 3, e116 (2007).

    PubMed  PubMed Central  Google Scholar 

  15. Chuva de Sousa Lopes, S. M. et al. X chromosome activity in mouse XX primordial germ cells. PLoS Genet. 4, e30 (2008).

    PubMed  PubMed Central  Google Scholar 

  16. Tam, P. P., Zhou, S. X. & Tan, S. S. X-chromosome activity of the mouse primordial germ cells revealed by the expression of an X-linked lacZ transgene. Development 120, 2925–2932 (1994).

    CAS  PubMed  Google Scholar 

  17. Monk, M. & McLaren, A. X-chromosome activity in foetal germ cells of the mouse. J. Embryol. Exp. Morphol. 63, 75–84 (1981).

    CAS  PubMed  Google Scholar 

  18. Seki, Y. et al. Cellular dynamics associated with the genome-wide epigenetic reprogramming in migrating primordial germ cells in mice. Development 134, 2627–2638 (2007).

    CAS  PubMed  Google Scholar 

  19. Seki, Y. et al. Extensive and orderly reprogramming of genome-wide chromatin modifications associated with specification and early development of germ cells in mice. Dev. Biol. 278, 440–458 (2005).

    CAS  PubMed  Google Scholar 

  20. McLaren, A. Primordial germ cells in the mouse. Dev. Biol. 262, 1–15 (2003).

    CAS  PubMed  Google Scholar 

  21. De Felici, M. in Oogenesis (eds Coticchio, G., Albertini, D. F. & De Santis, L.) 19–37 (Springer, 2012).

    Google Scholar 

  22. Leitch, H. G., Tang, W. W. & Surani, M. A. Primordial germ-cell development and epigenetic reprogramming in mammals. Curr. Top. Dev. Biol. 104, 149–187 (2013).

    CAS  PubMed  Google Scholar 

  23. Fuss, A. Über extraregionare Geschlechtszellen bei einem menschlichen Embryo von 4 Wochen. Anat. Am. 39, 407–409 (in German) (1911).

    Google Scholar 

  24. Witschi, E. Migration of the germ cells of human embryos from the yolk sac to the primitive gonadal folds. Contrib. Embryol. 32, 67–80 (1948).

    Google Scholar 

  25. Extavour, C. G. & Akam, M. Mechanisms of germ cell specification across the metazoans: epigenesis and preformation. Development 130, 5869–5884 (2003).

    CAS  PubMed  Google Scholar 

  26. Weismann, A., Parker, W. N. & Rönnfeldt, H. The Germ-plasm: A Theory of Heredity (Scribner, 1893).

    Google Scholar 

  27. Chatfield, J. et al. Stochastic specification of primordial germ cells from mesoderm precursors in axolotl embryos. Development 141, 2429–2440 (2014).

    CAS  PubMed  PubMed Central  Google Scholar 

  28. Ewen-Campen, B., Donoughe, S., Clarke, D. N. & Extavour, C. G. Germ cell specification requires zygotic mechanisms rather than germ plasm in a basally branching insect. Curr. Biol. 23, 835–842 (2013).

    CAS  PubMed  Google Scholar 

  29. Tam, P. P. & Loebel, D. A. Gene function in mouse embryogenesis: get set for gastrulation. Nat. Rev. Genet. 8, 368–381 (2007).

    CAS  PubMed  Google Scholar 

  30. Aramaki, S. et al. A mesodermal factor, T, specifies mouse germ cell fate by directly activating germline determinants. Dev. Cell 27, 516–529 (2013).

    CAS  PubMed  Google Scholar 

  31. Ying, Y. & Zhao, G. Q. Cooperation of endoderm-derived BMP2 and extraembryonic ectoderm-derived BMP4 in primordial germ cell generation in the mouse. Dev. Biol. 232, 484–492 (2001).

    CAS  PubMed  Google Scholar 

  32. Lawson, K. A. et al. Bmp4 is required for the generation of primordial germ cells in the mouse embryo. Genes Dev. 13, 424–436 (1999).

    CAS  PubMed  PubMed Central  Google Scholar 

  33. Ying, Y., Liu, X. M., Marble, A., Lawson, K. A. & Zhao, G. Q. Requirement of Bmp8b for the generation of primordial germ cells in the mouse. Mol. Endocrinol. 14, 1053–1063 (2000).

    CAS  PubMed  Google Scholar 

  34. de Sousa Lopes, S. M. et al. BMP signaling mediated by ALK2 in the visceral endoderm is necessary for the generation of primordial germ cells in the mouse embryo. Genes Dev. 18, 1838–1849 (2004).

    PubMed  PubMed Central  Google Scholar 

  35. Tremblay, K. D., Dunn, N. R. & Robertson, E. J. Mouse embryos lacking Smad1 signals display defects in extra-embryonic tissues and germ cell formation. Development 128, 3609–3621 (2001).

    CAS  PubMed  Google Scholar 

  36. Chu, G. C., Dunn, N. R., Anderson, D. C., Oxburgh, L. & Robertson, E. J. Differential requirements for Smad4 in TGFβ-dependent patterning of the early mouse embryo. Development 131, 3501–3512 (2004).

    CAS  PubMed  Google Scholar 

  37. Chang, H. & Matzuk, M. M. Smad5 is required for mouse primordial germ cell development. Mech. Dev. 104, 61–67 (2001).

    CAS  PubMed  Google Scholar 

  38. Liu, P. et al. Requirement for Wnt3 in vertebrate axis formation. Nat. Genet. 22, 361–365 (1999).

    CAS  PubMed  Google Scholar 

  39. Brennan, J. et al. Nodal signalling in the epiblast patterns the early mouse embryo. Nature 411, 965–969 (2001).

    CAS  PubMed  Google Scholar 

  40. Beddington, R. S. & Robertson, E. J. Axis development and early asymmetry in mammals. Cell 96, 195–209 (1999).

    CAS  PubMed  Google Scholar 

  41. Behringer, R. R., Wakamiya, M., Tsang, T. E. & Tam, P. P. A flattened mouse embryo: leveling the playing field. Genesis 28, 23–30 (2000).

    CAS  PubMed  Google Scholar 

  42. Hopf, C., Viebahn, C. & Puschel, B. BMP signals and the transcriptional repressor BLIMP1 during germline segregation in the mammalian embryo. Dev. Genes Evol. 221, 209–223 (2011).

    CAS  PubMed  PubMed Central  Google Scholar 

  43. Idkowiak, J., Weisheit, G., Plitzner, J. & Viebahn, C. Hypoblast controls mesoderm generation and axial patterning in the gastrulating rabbit embryo. Dev. Genes Evol. 214, 591–605 (2004).

    PubMed  Google Scholar 

  44. Valdez Magana, G., Rodriguez, A., Zhang, H., Webb, R. & Alberio, R. Paracrine effects of embryo-derived FGF4 and BMP4 during pig trophoblast elongation. Dev. Biol. 387, 15–27 (2014).

    CAS  PubMed  Google Scholar 

  45. Irie, N. et al. SOX17 Is a critical specifier of human primordial germ cell fate. Cell 160, 253–268 (2015). This paper shows robust in vitro induction of hPGCLCs from germline-competent hES cells and illustrates that SOX17 is essential for hPGC specification.

    CAS  PubMed  PubMed Central  Google Scholar 

  46. Kee, K., Gonsalves, J. M., Clark, A. T. & Pera, R. A. Bone morphogenetic proteins induce germ cell differentiation from human embryonic stem cells. Stem Cells Dev. 15, 831–837 (2006).

    CAS  PubMed  Google Scholar 

  47. Sasaki, K. et al. Robust in vitro induction of human germ cell fate from pluripotent stem cells. Cell Stem Cell 17, 178–194 (2015).

    CAS  PubMed  Google Scholar 

  48. Tam, P. P. & Zhou, S. X. The allocation of epiblast cells to ectodermal and germ-line lineages is influenced by the position of the cells in the gastrulating mouse embryo. Dev. Biol. 178, 124–132 (1996).

    CAS  PubMed  Google Scholar 

  49. Hayashi, K., Ohta, H., Kurimoto, K., Aramaki, S. & Saitou, M. Reconstitution of the mouse germ cell specification pathway in culture by pluripotent stem cells. Cell 146, 519–532 (2011). This paper shows robust in vitro induction of mPGCLCs from ground-state mES cells through a post-implantation epiblast-like state.

    CAS  PubMed  Google Scholar 

  50. Ying, Q. L. et al. The ground state of embryonic stem cell self-renewal. Nature 453, 519–523 (2008).

    CAS  PubMed  PubMed Central  Google Scholar 

  51. Boroviak, T., Loos, R., Bertone, P., Smith, A. & Nichols, J. The ability of inner-cell-mass cells to self-renew as embryonic stem cells is acquired following epiblast specification. Nat. Cell Biol. 16, 516–528 (2014).

    CAS  PubMed  PubMed Central  Google Scholar 

  52. Hayashi, K. et al. Offspring from oocytes derived from in vitro primordial germ cell-like cells in mice. Science 338, 971–975 (2012).

    CAS  PubMed  Google Scholar 

  53. Kee, K., Angeles, V. T., Flores, M., Nguyen, H. N. & Reijo Pera, R. A. Human DAZL, DAZ and BOULE genes modulate primordial germ-cell and haploid gamete formation. Nature 462, 222–225 (2009).

    CAS  PubMed  PubMed Central  Google Scholar 

  54. Wu, J. & Izpisua Belmonte, J. C. Dynamic pluripotent stem cell states and their applications. Cell Stem Cell 17, 509–525 (2015).

    CAS  PubMed  Google Scholar 

  55. Weinberger, L., Ayyash, M., Novershtern, N. & Hanna, J. H. Dynamic stem cell states: naive to primed pluripotency in rodents and humans. Nat. Rev. Mol. Cell Biol. 17, 155–169 (2016).

    CAS  PubMed  Google Scholar 

  56. Gafni, O. et al. Derivation of novel human ground state naive pluripotent stem cells. Nature 504, 282–286 (2013).

    CAS  PubMed  Google Scholar 

  57. Tang, W. W. et al. A unique gene regulatory network resets the human germline epigenome for development. Cell 161, 1453–1467 (2015).

    CAS  PubMed  PubMed Central  Google Scholar 

  58. Blakeley, P. et al. Defining the three cell lineages of the human blastocyst by single-cell RNA-seq. Development 142, 3151–3165 (2015).

    CAS  PubMed  PubMed Central  Google Scholar 

  59. Pastor, W. A. et al. Naive human pluripotent cells feature a methylation landscape devoid of blastocyst or germline memory. Cell Stem Cell 18, 323–329 (2016).

    CAS  PubMed  PubMed Central  Google Scholar 

  60. Takashima, Y. et al. Resetting transcription factor control circuitry toward ground-state pluripotency in human. Cell 158, 1254–1269 (2014).

    CAS  PubMed  PubMed Central  Google Scholar 

  61. Sugawa, F. et al. Human primordial germ cell commitment in vitro associates with a unique PRDM14 expression profile. EMBO J. 34, 1009–1024 (2015).

    CAS  PubMed  PubMed Central  Google Scholar 

  62. Kojima, Y. et al. The transcriptional and functional properties of mouse epiblast stem cells resemble the anterior primitive streak. Cell Stem Cell 14, 107–120 (2014).

    CAS  PubMed  Google Scholar 

  63. Buecker, C. et al. Reorganization of enhancer patterns in transition from naive to primed pluripotency. Cell Stem Cell 14, 838–853 (2014).

    CAS  PubMed  PubMed Central  Google Scholar 

  64. Kurimoto, K. et al. Quantitative dynamics of chromatin remodeling during germ cell specification from mouse embryonic stem cells. Cell Stem Cell 16, 517–532 (2015).

    CAS  PubMed  Google Scholar 

  65. Zylicz, J. J. et al. Chromatin dynamics and the role of G9a in gene regulation and enhancer silencing during early mouse development. eLife 4, e09571 (2015).

    PubMed  PubMed Central  Google Scholar 

  66. Murakami, K. et al. NANOG alone induces germ cells in primed epiblast in vitro by activation of enhancers. Nature 529, 403–407 (2016).

    CAS  PubMed  PubMed Central  Google Scholar 

  67. Kurimoto, K. et al. Complex genome-wide transcription dynamics orchestrated by Blimp1 for the specification of the germ cell lineage in mice. Genes Dev. 22, 1617–1635 (2008).

    CAS  PubMed  PubMed Central  Google Scholar 

  68. Saitou, M., Barton, S. C. & Surani, M. A. A molecular programme for the specification of germ cell fate in mice. Nature 418, 293–300 (2002).

    CAS  PubMed  Google Scholar 

  69. Vincent, S. D. et al. The zinc finger transcriptional repressor Blimp1/Prdm1 is dispensable for early axis formation but is required for specification of primordial germ cells in the mouse. Development 132, 1315–1325 (2005). This paper and reference 2 show that PRDM1 is the earliest lineage-restricted marker of mPGCs and that it is indispensable for mPGC specification.

    CAS  PubMed  Google Scholar 

  70. Grabole, N. et al. Prdm14 promotes germline fate and naive pluripotency by repressing FGF signalling and DNA methylation. EMBO Rep. 14, 629–637 (2013).

    CAS  PubMed  PubMed Central  Google Scholar 

  71. Martins, G. & Calame, K. Regulation and functions of Blimp-1 in T and B lymphocytes. Annu. Rev. Immunol. 26, 133–169 (2008).

    CAS  PubMed  Google Scholar 

  72. Ma, Z., Swigut, T., Valouev, A., Rada-Iglesias, A. & Wysocka, J. Sequence-specific regulator Prdm14 safeguards mouse ESCs from entering extraembryonic endoderm fates. Nat. Struct. Mol. Biol. 18, 120–127 (2011).

    CAS  PubMed  Google Scholar 

  73. Yamaji, M. et al. PRDM14 ensures naive pluripotency through dual regulation of signaling and epigenetic pathways in mouse embryonic stem cells. Cell Stem Cell 12, 368–382 (2013).

    CAS  PubMed  Google Scholar 

  74. Auman, H. J. et al. Transcription factor AP-2γ is essential in the extra-embryonic lineages for early postimplantation development. Development 129, 2733–2747 (2002).

    CAS  PubMed  Google Scholar 

  75. Werling, U. & Schorle, H. Transcription factor gene AP-2γ essential for early murine development. Mol. Cell. Biol. 22, 3149–3156 (2002).

    CAS  PubMed  PubMed Central  Google Scholar 

  76. Nady, N. et al. ETO family protein Mtgr1 mediates Prdm14 functions in stem cell maintenance and primordial germ cell formation. eLife 4, e10150 (2015).

    PubMed  PubMed Central  Google Scholar 

  77. Tu, S. et al. Co-repressor CBFA2T2 regulates pluripotency and germline development. Nature 534, 387–390 (2016). References 76 and 77 show that co-repressor CBFA2T2 interacts with PRDM14 and thus has a role in the regulation of pluripotency and mPGC specification.

    PubMed  PubMed Central  Google Scholar 

  78. Fog, C. K., Galli, G. G. & Lund, A. H. PRDM proteins: important players in differentiation and disease. Bioessays 34, 50–60 (2012).

    CAS  PubMed  Google Scholar 

  79. Scholer, H. R., Dressler, G. R., Balling, R., Rohdewohld, H. & Gruss, P. Oct-4: a germline-specific transcription factor mapping to the mouse t-complex. EMBO J. 9, 2185–2195 (1990).

    CAS  PubMed  PubMed Central  Google Scholar 

  80. Yeom, Y. I. et al. Germline regulatory element of Oct-4 specific for the totipotent cycle of embryonal cells. Development 122, 881–894 (1996).

    CAS  PubMed  Google Scholar 

  81. Yabuta, Y., Kurimoto, K., Ohinata, Y., Seki, Y. & Saitou, M. Gene expression dynamics during germline specification in mice identified by quantitative single-cell gene expression profiling. Biol. Reprod. 75, 705–716 (2006).

    CAS  PubMed  Google Scholar 

  82. Sato, M. et al. Identification of PGC7, a new gene expressed specifically in preimplantation embryos and germ cells. Mech. Dev. 113, 91–94 (2002).

    CAS  PubMed  Google Scholar 

  83. Leitch, H. G. et al. Embryonic germ cells from mice and rats exhibit properties consistent with a generic pluripotent ground state. Development 137, 2279–2287 (2010).

    CAS  PubMed  PubMed Central  Google Scholar 

  84. Matsui, Y., Zsebo, K. & Hogan, B. L. Derivation of pluripotential embryonic stem cells from murine primordial germ cells in culture. Cell 70, 841–847 (1992).

    CAS  PubMed  Google Scholar 

  85. Durcova-Hills, G., Tang, F., Doody, G., Tooze, R. & Surani, M. A. Reprogramming primordial germ cells into pluripotent stem cells. PLoS ONE 3, e3531 (2008).

    PubMed  PubMed Central  Google Scholar 

  86. Kehler, J. et al. Oct4 is required for primordial germ cell survival. EMBO Rep. 5, 1078–1083 (2004).

    CAS  PubMed  PubMed Central  Google Scholar 

  87. Yamaguchi, S. et al. Conditional knockdown of Nanog induces apoptotic cell death in mouse migrating primordial germ cells. Development 136, 4011–4020 (2009).

    CAS  PubMed  Google Scholar 

  88. Chambers, I. et al. Nanog safeguards pluripotency and mediates germline development. Nature 450, 1230–1234 (2007).

    CAS  PubMed  Google Scholar 

  89. Campolo, F. et al. Essential role of Sox2 for the establishment and maintenance of the germ cell line. Stem Cells 31, 1408–1421 (2013).

    CAS  PubMed  Google Scholar 

  90. Yamaguchi, Y. L. et al. Sall4 is essential for mouse primordial germ cell specification by suppressing somatic cell program genes. Stem Cells 33, 289–300 (2015).

    CAS  PubMed  Google Scholar 

  91. Guo, F. et al. The transcriptome and DNA methylome landscapes of human primordial germ cells. Cell 161, 1437–1452 (2015). This article and reference 57 reveal the transcriptional network and epigenetic reprogramming dynamics in hPGCs isolated from human embryos, using high-quality RNA-seq and bisulfite sequencing (BS-seq) analyses.

    CAS  PubMed  Google Scholar 

  92. Perrett, R. M. et al. The early human germ cell lineage does not express SOX2 during in vivo development or upon in vitro culture. Biol. Reprod. 78, 852–858 (2008).

    CAS  PubMed  Google Scholar 

  93. de Jong, J. et al. Differential expression of SOX17 and SOX2 in germ cells and stem cells has biological and clinical implications. J. Pathol. 215, 21–30 (2008).

    CAS  PubMed  Google Scholar 

  94. Hara, K. et al. Evidence for crucial role of hindgut expansion in directing proper migration of primordial germ cells in mouse early embryogenesis. Dev. Biol. 330, 427–439 (2009).

    CAS  PubMed  Google Scholar 

  95. Sarkar, A. & Hochedlinger, K. The Sox family of transcription factors: versatile regulators of stem and progenitor cell fate. Cell Stem Cell 12, 15–30 (2013).

    CAS  PubMed  PubMed Central  Google Scholar 

  96. Kanai-Azuma, M. et al. Depletion of definitive gut endoderm in Sox17-null mutant mice. Development 129, 2367–2379 (2002).

    CAS  PubMed  Google Scholar 

  97. Kim, I., Saunders, T. L. & Morrison, S. J. Sox17 dependence distinguishes the transcriptional regulation of fetal from adult hematopoietic stem cells. Cell 130, 470–483 (2007).

    CAS  PubMed  PubMed Central  Google Scholar 

  98. Kamachi, Y. & Kondoh, H. Sox proteins: regulators of cell fate specification and differentiation. Development 140, 4129–4144 (2013).

    CAS  PubMed  Google Scholar 

  99. Nakagawa, M. et al. Generation of induced pluripotent stem cells without Myc from mouse and human fibroblasts. Nat. Biotechnol. 26, 101–106 (2008).

    CAS  PubMed  Google Scholar 

  100. Niakan, K. K. et al. Sox17 promotes differentiation in mouse embryonic stem cells by directly regulating extraembryonic gene expression and indirectly antagonizing self-renewal. Genes Dev. 24, 312–326 (2010).

    CAS  PubMed  PubMed Central  Google Scholar 

  101. Seguin, C. A., Draper, J. S., Nagy, A. & Rossant, J. Establishment of endoderm progenitors by SOX transcription factor expression in human embryonic stem cells. Cell Stem Cell 3, 182–195 (2008).

    CAS  PubMed  Google Scholar 

  102. Stefanovic, S. et al. Interplay of Oct4 with Sox2 and Sox17: a molecular switch from stem cell pluripotency to specifying a cardiac fate. J. Cell Biol. 186, 665–673 (2009).

    CAS  PubMed  PubMed Central  Google Scholar 

  103. Aksoy, I. et al. Oct4 switches partnering from Sox2 to Sox17 to reinterpret the enhancer code and specify endoderm. EMBO J. 32, 938–953 (2013).

    CAS  PubMed  PubMed Central  Google Scholar 

  104. Niwa, H., Miyazaki, J. & Smith, A. G. Quantitative expression of Oct-3/4 defines differentiation, dedifferentiation or self-renewal of ES cells. Nat. Genet. 24, 372–376 (2000).

    CAS  PubMed  Google Scholar 

  105. Maruyama, M., Ichisaka, T., Nakagawa, M. & Yamanaka, S. Differential roles for Sox15 and Sox2 in transcriptional control in mouse embryonic stem cells. J. Biol. Chem. 280, 24371–24379 (2005).

    CAS  PubMed  Google Scholar 

  106. Masui, S. et al. Pluripotency governed by Sox2 via regulation of Oct3/4 expression in mouse embryonic stem cells. Nat. Cell Biol. 9, 625–635 (2007).

    CAS  PubMed  Google Scholar 

  107. Chia, N. Y. et al. A genome-wide RNAi screen reveals determinants of human embryonic stem cell identity. Nature 468, 316–320 (2010).

    CAS  PubMed  Google Scholar 

  108. Tsuneyoshi, N. et al. PRDM14 suppresses expression of differentiation marker genes in human embryonic stem cells. Biochem. Biophys. Res. Commun. 367, 899–905 (2008).

    CAS  PubMed  Google Scholar 

  109. Messerschmidt, D. M., Knowles, B. B. & Solter, D. DNA methylation dynamics during epigenetic reprogramming in the germline and preimplantation embryos. Genes Dev. 28, 812–828 (2014).

    CAS  PubMed  PubMed Central  Google Scholar 

  110. Saitou, M., Kagiwada, S. & Kurimoto, K. Epigenetic reprogramming in mouse pre-implantation development and primordial germ cells. Development 139, 15–31 (2012).

    CAS  PubMed  Google Scholar 

  111. Kobayashi, H. et al. High-resolution DNA methylome analysis of primordial germ cells identifies gender-specific reprogramming in mice. Genome Res. 23, 616–627 (2013).

    CAS  PubMed  PubMed Central  Google Scholar 

  112. Sharif, J. et al. The SRA protein Np95 mediates epigenetic inheritance by recruiting Dnmt1 to methylated DNA. Nature 450, 908–912 (2007).

    CAS  PubMed  Google Scholar 

  113. Kagiwada, S., Kurimoto, K., Hirota, T., Yamaji, M. & Saitou, M. Replication-coupled passive DNA demethylation for the erasure of genome imprints in mice. EMBO J. 32, 340–353 (2013).

    CAS  PubMed  Google Scholar 

  114. Ohno, R. et al. A replication-dependent passive mechanism modulates DNA demethylation in mouse primordial germ cells. Development 140, 2892–2903 (2013).

    CAS  PubMed  Google Scholar 

  115. Arand, J. et al. Selective impairment of methylation maintenance is the major cause of DNA methylation reprogramming in the early embryo. Epigenetics Chromatin 8, 1 (2015).

    CAS  PubMed  PubMed Central  Google Scholar 

  116. Hackett, J. A., Zylicz, J. J. & Surani, M. A. Parallel mechanisms of epigenetic reprogramming in the germline. Trends Genet. 28, 164–174 (2012).

    CAS  PubMed  Google Scholar 

  117. Yamaguchi, S. et al. Dynamics of 5-methylcytosine and 5-hydroxymethylcytosine during germ cell reprogramming. Cell Res. 23, 329–339 (2013).

    CAS  PubMed  PubMed Central  Google Scholar 

  118. Yamaguchi, S., Shen, L., Liu, Y., Sendler, D. & Zhang, Y. Role of Tet1 in erasure of genomic imprinting. Nature 504, 460–464 (2013).

    CAS  PubMed  PubMed Central  Google Scholar 

  119. Dawlaty, M. M. et al. Combined deficiency of Tet1 and Tet2 causes epigenetic abnormalities but is compatible with postnatal development. Dev. Cell 24, 310–323 (2013).

    CAS  PubMed  PubMed Central  Google Scholar 

  120. Yamaguchi, S. et al. Tet1 controls meiosis by regulating meiotic gene expression. Nature 492, 443–447 (2012).

    CAS  PubMed  PubMed Central  Google Scholar 

  121. Gkountela, S. et al. DNA demethylation dynamics in the human prenatal germline. Cell 161, 1425–1436 (2015).

    CAS  PubMed  PubMed Central  Google Scholar 

  122. Gaskell, T. L., Esnal, A., Robinson, L. L., Anderson, R. A. & Saunders, P. T. Immunohistochemical profiling of germ cells within the human fetal testis: identification of three subpopulations. Biol. Reprod. 71, 2012–2021 (2004).

    CAS  PubMed  Google Scholar 

  123. Kerr, C. L., Hill, C. M., Blumenthal, P. D. & Gearhart, J. D. Expression of pluripotent stem cell markers in the human fetal ovary. Hum. Reprod. 23, 589–599 (2008).

    CAS  PubMed  Google Scholar 

  124. Kerr, C. L., Hill, C. M., Blumenthal, P. D. & Gearhart, J. D. Expression of pluripotent stem cell markers in the human fetal testis. Stem Cells 26, 412–421 (2008).

    PubMed  Google Scholar 

  125. Wermann, H. et al. Global DNA methylation in fetal human germ cells and germ cell tumours: association with differentiation and cisplatin resistance. J. Pathol. 221, 433–442 (2010).

    CAS  PubMed  Google Scholar 

  126. Smith, Z. D. & Meissner, A. DNA methylation: roles in mammalian development. Nat. Rev. Genet. 14, 204–220 (2013).

    CAS  PubMed  Google Scholar 

  127. Tsumura, A. et al. Maintenance of self-renewal ability of mouse embryonic stem cells in the absence of DNA methyltransferases Dnmt1, Dnmt3a and Dnmt3b. Genes Cells 11, 805–814 (2006).

    CAS  PubMed  Google Scholar 

  128. Brinkman, A. B. et al. Sequential ChIP-bisulfite sequencing enables direct genome-scale investigation of chromatin and DNA methylation cross-talk. Genome Res. 22, 1128–1138 (2012).

    CAS  PubMed  PubMed Central  Google Scholar 

  129. Walter, M., Teissandier, A., Perez-Palacios, R. & Bourc'his, D. An epigenetic switch ensures transposon repression upon dynamic loss of DNA methylation in embryonic stem cells. eLife 5, e11418 (2016). This paper shows that repressive chromatin modifications repress retrotransposons and safeguard genome stability during chemical-induced global DNA demethylation in mES cells.

    PubMed  PubMed Central  Google Scholar 

  130. Ancelin, K. et al. Blimp1 associates with Prmt5 and directs histone arginine methylation in mouse germ cells. Nat. Cell Biol. 8, 623–630 (2006).

    CAS  PubMed  Google Scholar 

  131. Ng, J. H. et al. In vivo epigenomic profiling of germ cells reveals germ cell molecular signatures. Dev. Cell 24, 324–333 (2013).

    CAS  PubMed  Google Scholar 

  132. Liu, S. et al. Setdb1 is required for germline development and silencing of H3K9me3-marked endogenous retroviruses in primordial germ cells. Genes Dev. 28, 2041–2055 (2014).

    CAS  PubMed  PubMed Central  Google Scholar 

  133. Kim, S. et al. PRMT5 protects genomic integrity during global DNA demethylation in primordial germ cells and preimplantation embryos. Mol. Cell 56, 564–579 (2014).

    CAS  PubMed  PubMed Central  Google Scholar 

  134. Guo, H. et al. The DNA methylation landscape of human early embryos. Nature 511, 606–610 (2014).

    CAS  PubMed  Google Scholar 

  135. Smith, Z. D. et al. DNA methylation dynamics of the human preimplantation embryo. Nature 511, 611–615 (2014).

    CAS  PubMed  PubMed Central  Google Scholar 

  136. Lane, N. et al. Resistance of IAPs to methylation reprogramming may provide a mechanism for epigenetic inheritance in the mouse. Genesis 35, 88–93 (2003).

    CAS  PubMed  Google Scholar 

  137. Jeltsch, A. & Jurkowska, R. Z. New concepts in DNA methylation. Trends Biochem. Sci. 39, 310–318 (2014).

    CAS  PubMed  Google Scholar 

  138. Wolf, G., Greenberg, D. & Macfarlan, T. S. Spotting the enemy within: targeted silencing of foreign DNA in mammalian genomes by the Krüppel-associated box zinc finger protein family. Mob. DNA 6, 17 (2015).

    PubMed  PubMed Central  Google Scholar 

  139. Jacobs, F. M. et al. An evolutionary arms race between KRAB zinc-finger genes ZNF91/93 and SVA/L1 retrotransposons. Nature 516, 242–245 (2014).

    CAS  PubMed  PubMed Central  Google Scholar 

  140. Li, X. et al. A maternal-zygotic effect gene, Zfp57, maintains both maternal and paternal imprints. Dev. Cell 15, 547–557 (2008).

    CAS  PubMed  PubMed Central  Google Scholar 

  141. Mackay, D. J. et al. Hypomethylation of multiple imprinted loci in individuals with transient neonatal diabetes is associated with mutations in ZFP57. Nat. Genet. 40, 949–951 (2008).

    CAS  PubMed  Google Scholar 

  142. Williams, Z. et al. Discovery and characterization of piRNAs in the human fetal ovary. Cell Rep. 13, 854–863 (2015).

    CAS  PubMed  Google Scholar 

  143. Baudat, F. et al. PRDM9 is a major determinant of meiotic recombination hotspots in humans and mice. Science 327, 836–840 (2010).

    CAS  PubMed  Google Scholar 

  144. Daxinger, L. & Whitelaw, E. Understanding transgenerational epigenetic inheritance via the gametes in mammals. Nat. Rev. Genet. 13, 153–162 (2012).

    CAS  PubMed  Google Scholar 

  145. Bohacek, J. & Mansuy, I. M. Molecular insights into transgenerational non-genetic inheritance of acquired behaviours. Nat. Rev. Genet. 16, 641–652 (2015).

    CAS  PubMed  Google Scholar 

  146. Heard, E. & Martienssen, R. A. Transgenerational epigenetic inheritance: myths and mechanisms. Cell 157, 95–109 (2014).

    CAS  PubMed  PubMed Central  Google Scholar 

  147. Surani, M. A., Barton, S. C. & Norris, M. L. Development of reconstituted mouse eggs suggests imprinting of the genome during gametogenesis. Nature 308, 548–550 (1984).

    CAS  PubMed  Google Scholar 

  148. McGrath, J. & Solter, D. Completion of mouse embryogenesis requires both the maternal and paternal genomes. Cell 37, 179–183 (1984).

    CAS  PubMed  Google Scholar 

  149. Radford, E. J. et al. In utero undernourishment perturbs the adult sperm methylome and intergenerational metabolism. Science 345, 1255903 (2014).

    PubMed  PubMed Central  Google Scholar 

  150. Shea, J. M. et al. Genetic and epigenetic variation, but not diet, shape the sperm methylome. Dev. Cell 35, 750–758 (2015).

    CAS  PubMed  PubMed Central  Google Scholar 

  151. Chen, Q. et al. Sperm tsRNAs contribute to intergenerational inheritance of an acquired metabolic disorder. Science 351, 397–400 (2016).

    CAS  PubMed  Google Scholar 

  152. Sharma, U. et al. Biogenesis and function of tRNA fragments during sperm maturation and fertilization in mammals. Science 351, 391–396 (2016).

    CAS  PubMed  Google Scholar 

  153. Johnson, A. D. & Alberio, R. Primordial germ cells: the first cell lineage or the last cells standing? Development 142, 2730–2739 (2015).

    CAS  PubMed  PubMed Central  Google Scholar 

  154. Zhou, Q. et al. Complete meiosis from embryonic stem cell-derived germ cells in vitro. Cell Stem Cell 18, 330–340 (2016).

    CAS  PubMed  Google Scholar 

  155. Zhang, X. et al. Pax6 is a human neuroectoderm cell fate determinant. Cell Stem Cell 7, 90–100 (2010).

    CAS  PubMed  PubMed Central  Google Scholar 

  156. Rossant, J. & Tam, P. P. Blastocyst lineage formation, early embryonic asymmetries and axis patterning in the mouse. Development 136, 701–713 (2009).

    CAS  PubMed  Google Scholar 

  157. De Paepe, C., Krivega, M., Cauffman, G., Geens, M. & Van de Velde, H. Totipotency and lineage segregation in the human embryo. Mol. Hum. Reprod. 20, 599–618 (2014).

    CAS  PubMed  Google Scholar 

  158. Niakan, K. K. & Eggan, K. Analysis of human embryos from zygote to blastocyst reveals distinct gene expression patterns relative to the mouse. Dev. Biol. 375, 54–64 (2013).

    CAS  PubMed  Google Scholar 

  159. O'Leary, T. et al. Tracking the progression of the human inner cell mass during embryonic stem cell derivation. Nat. Biotechnol. 30, 278–282 (2012).

    CAS  PubMed  Google Scholar 

  160. Bedzhov, I. & Zernicka-Goetz, M. Self-organizing properties of mouse pluripotent cells initiate morphogenesis upon implantation. Cell 156, 1032–1044 (2014).

    CAS  PubMed  PubMed Central  Google Scholar 

  161. Moore, K. L., Persaud, T. V. N. & Torchia, M. G. The Developing Human: Clinically Oriented Embryology (Elsevier/Saunders, 2013).

    Google Scholar 

  162. Hackett, J. A. & Surani, M. A. Regulatory principles of pluripotency: from the ground state up. Cell Stem Cell 15, 416–430 (2014).

    CAS  PubMed  Google Scholar 

  163. Evans, M. J. & Kaufman, M. H. Establishment in culture of pluripotential cells from mouse embryos. Nature 292, 154–156 (1981).

    CAS  PubMed  Google Scholar 

  164. Martin, G. R. Isolation of a pluripotent cell line from early mouse embryos cultured in medium conditioned by teratocarcinoma stem cells. Proc. Natl Acad. Sci. USA 78, 7634–7638 (1981).

    CAS  PubMed  Google Scholar 

  165. Brons, I. G. et al. Derivation of pluripotent epiblast stem cells from mammalian embryos. Nature 448, 191–195 (2007).

    CAS  PubMed  Google Scholar 

  166. Tesar, P. J. et al. New cell lines from mouse epiblast share defining features with human embryonic stem cells. Nature 448, 196–199 (2007).

    CAS  PubMed  Google Scholar 

  167. Huang, Y., Osorno, R., Tsakiridis, A. & Wilson, V. In vivo differentiation potential of epiblast stem cells revealed by chimeric embryo formation. Cell Rep. 2, 1571–1578 (2012).

    CAS  PubMed  Google Scholar 

  168. Toyooka, Y., Tsunekawa, N., Akasu, R. & Noce, T. Embryonic stem cells can form germ cells in vitro. Proc. Natl Acad. Sci. USA 100, 11457–11462 (2003).

    CAS  PubMed  Google Scholar 

  169. Hubner, K. et al. Derivation of oocytes from mouse embryonic stem cells. Science 300, 1251–1256 (2003).

    PubMed  Google Scholar 

  170. Hayashi, K. & Surani, M. A. Self-renewing epiblast stem cells exhibit continual delineation of germ cells with epigenetic reprogramming in vitro. Development 136, 3549–3556 (2009).

    CAS  PubMed  PubMed Central  Google Scholar 

  171. Thomson, J. A. et al. Embryonic stem cell lines derived from human blastocysts. Science 282, 1145–1147 (1998).

    CAS  PubMed  Google Scholar 

  172. Nichols, J. & Smith, A. Naive and primed pluripotent states. Cell Stem Cell 4, 487–492 (2009).

    CAS  PubMed  Google Scholar 

  173. Vallier, L., Alexander, M. & Pedersen, R. A. Activin/Nodal and FGF pathways cooperate to maintain pluripotency of human embryonic stem cells. J. Cell Sci. 118, 4495–4509 (2005).

    CAS  PubMed  Google Scholar 

  174. Son, M. Y., Choi, H., Han, Y. M. & Cho, Y. S. Unveiling the critical role of REX1 in the regulation of human stem cell pluripotency. Stem Cells 31, 2374–2387 (2013).

    CAS  PubMed  Google Scholar 

  175. Clark, A. T. et al. Spontaneous differentiation of germ cells from human embryonic stem cells in vitro. Hum. Mol. Genet. 13, 727–739 (2004).

    CAS  PubMed  Google Scholar 

  176. Rao, J. et al. Stepwise clearance of repressive roadblocks drives cardiac induction in human ESCs. Cell Stem Cell 18, 341–353 (2016).

    CAS  PubMed  Google Scholar 

  177. Lin, I. Y. et al. Suppression of the SOX2 neural effector gene by PRDM1 promotes human germ cell fate in embryonic stem cells. Stem Cell Rep. 2, 189–204 (2014).

    CAS  Google Scholar 

  178. Du, J., Johnson, L. M., Jacobsen, S. E. & Patel, D. J. DNA methylation pathways and their crosstalk with histone methylation. Nat. Rev. Mol. Cell Biol. 16, 519–532 (2015).

    CAS  PubMed  PubMed Central  Google Scholar 

  179. Gkountela, S. et al. The ontogeny of cKIT+ human primordial germ cells proves to be a resource for human germ line reprogramming, imprint erasure and in vitro differentiation. Nat. Cell Biol. 15, 113–122 (2013).

    CAS  PubMed  Google Scholar 

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Acknowledgements

The authors thank J. Hackett for reading of the manuscript and members of the Surani laboratory for helpful discussions. Our work was funded by a Wellcome Trust Investigator Award to M.A.S, and by a Britain Israel Research and Academic Exchange (BIRAX) Initiative and a Croucher Cambridge International Scholarship to W.W.C.T. Research at the Gurdon Institute is funded by a core grant from the Wellcome Trust (092096) and Cancer Research UK (C6946/A14492). The authors apologize to colleagues whose work could not be cited owing to length limitations.

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Glossary

Totipotent

The ability of a cell to give rise to all cell types (both embryonic and extra-embryonic) of an organism.

Pluripotent epiblast cells

Cells derived from the inner cell mass of a blastocyst that give rise to all lineages of the embryo proper.

Allantois

A membranous sac that develops from the mesoderm (in mice) or the hindgut endoderm (in humans) during early embryonic development. The allantois contributes to the formation of the umbilical cord and placenta.

Genomic imprint

An epigenetic phenomenon that results in monoallelic gene expression in a parent-of-origin-dependent manner.

Gastrulation

The developmental process in which the three germ layers (that is, the ectoderm, mesoderm and definitive endoderm) of the embryo are formed.

Primitive streak

A structure at the posterior end of the embryo where epiblast cells ingress to form the mesoderm and the definitive endoderm. Formation of the primitive streak is the first visible sign of gastrulation.

Nodal signalling

A signal transduction pathway that is essential for the formation of the mesoderm and the endoderm, and for axis determination in vertebrates. Nodal signalling is activated by transforming growth factor-β (TGFβ) family factors Activin and Nodal, and is transduced by SMAD2 and SMAD3.

Trophoblast

The outermost layer of extra-embryonic tissues that attaches the embryo to the uterine wall and forms the placenta.

Pluripotent states

Pluripotency refers to the ability of a cell to differentiate into any cell of the three germ layers in the embryo proper. The pre-implantation epiblast represents a naive pluripotent state, whereas the post-implantation epiblast (poised for lineage differentiation) represents a 'primed' pluripotent state.

Lineage specifiers

Transcription factors that direct competent cells to differentiate into a specific cell lineage.

Inner cell mass

(ICM). A compact mass of cells located at the embryonic pole of the blastocyst. The ICM gives rise to the epiblast and the hypoblast, which form the embryo proper and the yolk sac, respectively.

Retrotransposons

DNA elements that can amplify themselves in the genome. During the process of retrotransposition, retrotransposon DNA is first transcribed into RNA, then reverse transcribed into DNA, followed by insertion into a new genomic site.

Krüpple-associated box zinc-finger protein

(KRAB-ZFP). The largest individual family of transcriptional repressors in mammals. KRAB-ZFPs contain DNA-binding C2H2 zinc-fingers and a KRAB domain that interacts with the KRAB-associated protein 1 (KAP1) co-repressor complex for epigenetic silencing.

Transgenerational epigenetic inheritance

(TEI). Transmission of epigenetic information through the germ line that affects phenotypic traits in more than one generation without changes in DNA sequence.

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Tang, W., Kobayashi, T., Irie, N. et al. Specification and epigenetic programming of the human germ line. Nat Rev Genet 17, 585–600 (2016). https://doi.org/10.1038/nrg.2016.88

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