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A protein interaction network for pluripotency of embryonic stem cells

Abstract

Embryonic stem (ES) cells are pluripotent1,2 and of therapeutic potential in regenerative medicine3,4. Understanding pluripotency at the molecular level should illuminate fundamental properties of stem cells and the process of cellular reprogramming. Through cell fusion the embryonic cell phenotype can be imposed on somatic cells, a process promoted by the homeodomain protein Nanog5, which is central to the maintenance of ES cell pluripotency6,7. Nanog is thought to function in concert with other factors such as Oct4 (ref. 8) and Sox2 (ref. 9) to establish ES cell identity. Here we explore the protein network in which Nanog operates in mouse ES cells. Using affinity purification of Nanog under native conditions followed by mass spectrometry, we have identified physically associated proteins. In an iterative fashion we also identified partners of several Nanog-associated proteins (including Oct4), validated the functional relevance of selected newly identified components and constructed a protein interaction network. The network is highly enriched for nuclear factors that are individually critical for maintenance of the ES cell state and co-regulated on differentiation. The network is linked to multiple co-repressor pathways and is composed of numerous proteins whose encoding genes are putative direct transcriptional targets of its members. This tight protein network seems to function as a cellular module dedicated to pluripotency.

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Figure 1: Protein complexes containing Nanog protein in mouse ES cells.
Figure 2: Confirmation of Nanog association by co-immunoprecipitation in ES cells.
Figure 3: Functional validation by RNA-mediated interference.
Figure 4: A protein interaction network in ES cells.

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References

  1. 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)

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

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

    Article  ADS  CAS  PubMed  Google Scholar 

  3. Donovan, P. J. & Gearhart, J. The end of the beginning for pluripotent stem cells. Nature 414, 92–97 (2001)

    Article  ADS  CAS  PubMed  Google Scholar 

  4. Prelle, K., Zink, N. & Wolf, E. Pluripotent stem cells—model of embryonic development, tool for gene targeting, and basis of cell therapy. Anat. Histol. Embryol. 31, 169–186 (2002)

    Article  PubMed  Google Scholar 

  5. Silva, J., Chambers, I., Pollard, S. & Smith, A. Nanog promotes transfer of pluripotency after cell fusion. Nature 441, 997–1001 (2006)

    Article  ADS  CAS  PubMed  Google Scholar 

  6. Mitsui, K. et al. The homeoprotein Nanog is required for maintenance of pluripotency in mouse epiblast and ES cells. Cell 113, 631–642 (2003)

    Article  CAS  PubMed  Google Scholar 

  7. Chambers, I. et al. Functional expression cloning of Nanog, a pluripotency sustaining factor in embryonic stem cells. Cell 113, 643–655 (2003)

    Article  CAS  PubMed  Google Scholar 

  8. Nichols, J. et al. Formation of pluripotent stem cells in the mammalian embryo depends on the POU transcription factor Oct4. Cell 95, 379–391 (1998)

    Article  CAS  PubMed  Google Scholar 

  9. Avilion, A. A. et al. Multipotent cell lineages in early mouse development depend on SOX2 function. Genes Dev. 17, 126–140 (2003)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  10. de Boer, E. et al. Efficient biotinylation and single-step purification of tagged transcription factors in mammalian cells and transgenic mice. Proc. Natl Acad. Sci. USA 100, 7480–7485 (2003)

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

  11. Krogan, N. J. et al. Global landscape of protein complexes in the yeast Saccharomyces cerevisiae.. Nature 440, 637–643 (2006)

    Article  ADS  CAS  PubMed  Google Scholar 

  12. Niakan, K. K. et al. Novel role for the orphan nuclear receptor Dax1 in embryogenesis, different from steroidogenesis. Mol. Genet. Metab. 88, 261–271 (2006)

    Article  CAS  PubMed  Google Scholar 

  13. Sakaki-Yumoto, M. et al. The murine homolog of SALL4, a causative gene in Okihiro syndrome, is essential for embryonic stem cell proliferation, and cooperates with Sall1 in anorectal, heart, brain and kidney development. Development 133, 3005–3013 (2006)

    Article  CAS  PubMed  Google Scholar 

  14. Mackler, S. A., Homan, Y. X., Korutla, L., Conti, A. C. & Blendy, J. A. The mouse nac1 gene, encoding a cocaine-regulated Bric-a-brac Tramtrac Broad complex/Pox virus and Zinc finger protein, is regulated by AP1. Neuroscience 121, 355–361 (2003)

    Article  CAS  PubMed  Google Scholar 

  15. Mackler, S. A. et al. NAC-1 is a brain POZ/BTB protein that can prevent cocaine-induced sensitization in the rat. J. Neurosci. 20, 6210–6217 (2000)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  16. Law, D. J., Du, M., Law, G. L. & Merchant, J. L. ZBP-99 defines a conserved family of transcription factors and regulates ornithine decarboxylase gene expression. Biochem. Biophys. Res. Commun. 262, 113–120 (1999)

    Article  CAS  PubMed  Google Scholar 

  17. Thompson, J. R. & Gudas, L. J. Retinoic acid induces parietal endoderm but not primitive endoderm and visceral endoderm differentiation in F9 teratocarcinoma stem cells with a targeted deletion of the Rex-1 (Zfp-42) gene. Mol. Cell. Endocrinol. 195, 119–133 (2002)

    Article  CAS  PubMed  Google Scholar 

  18. Batagelj, V. & Mrvar, A. Pajek—program for large network analysis. Connections 21, 47–57 (1998)

    MATH  Google Scholar 

  19. Loh, Y. H. et al. The Oct4 and Nanog transcription network regulates pluripotency in mouse embryonic stem cells. Nature Genet. 38, 431–440 (2006)

    Article  CAS  PubMed  Google Scholar 

  20. Boyer, L. A. et al. Core transcriptional regulatory circuitry in human embryonic stem cells. Cell 122, 947–956 (2005)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  21. Albert, R., Jeong, H. & Barabasi, A. L. Error and attack tolerance of complex networks. Nature 406, 378–382 (2000)

    Article  ADS  CAS  PubMed  Google Scholar 

  22. Lauberth, S. M. & Rauchman, M. A conserved twelve amino acid motif in sall1 recruits nuRD. J. Biol. Chem. 281, 23922–23931 (2006)

    Article  CAS  PubMed  Google Scholar 

  23. Korutla, L., Wang, P. J. & Mackler, S. A. The POZ/BTB protein NAC1 interacts with two different histone deacetylases in neuronal-like cultures. J. Neurochem. 94, 786–793 (2005)

    Article  CAS  PubMed  Google Scholar 

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

    Article  CAS  PubMed  Google Scholar 

  25. Hatano, S. Y. et al. Pluripotential competence of cells associated with Nanog activity. Mech. Dev. 122, 67–79 (2005)

    Article  CAS  PubMed  Google Scholar 

  26. Takahashi, K. & Yamanaka, S. Induction of pluripotent stem cells from mouse embryonic and adult fibroblast cultures by defined factors. Cell 126, 663–676 (2006)

    Article  CAS  PubMed  Google Scholar 

  27. Lee, J., Rhee, B. K., Bae, G. Y., Han, Y. M. & Kim, J. Stimulation of Oct-4 activity by Ewing’s sarcoma protein. Stem Cells 23, 738–751 (2005)

    Article  CAS  PubMed  Google Scholar 

  28. Perez-Iratxeta, C. et al. Study of stem cell function using microarray experiments. FEBS Lett. 579, 1795–1801 (2005)

    Article  CAS  PubMed  Google Scholar 

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Acknowledgements

We thank A. Cantor for biotin tagging constructs and for advice on affinity purification and chromatography; Y. Fujiwara and M. Kaku for technical assistance and for Oct4–GFP ES cells; T. De Lange for Rif1 antibody; S. Mackler for Nac1 antibody; S. Lowe and S. Elledge for shRNA vectors; M. Vidal and A.-L. Barabasi for advice and discussion on networks; and R. Tomaino and S. Gygi for performing LC–MS/MS and for providing advice and assistance in data collection and analysis. S.H.O. is an Investigator of the HHMI. Author Contributions S.R. and J.C. contributed equally to this study. J.W. and S.H.O. conceived and initiated the study. J.W., J.C., X.S., D.N.L. and T.W.T. performed the experiments. S.R. and J.W. analysed data and bioinformatics of the network. J.W. and S.H.O. wrote the manuscript.

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Correspondence to Stuart H. Orkin.

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Supplementary information

Supplementary Notes

This file contains Supplementary Methods, Supplementary Figure Legends and Supplementary Tables 1–3. (DOC 207 kb)

Supplementary Figures

This file contains Supplementary Figures 1–8. (PDF 1871 kb)

Supplementary Data 1

Common background proteins in BirA samples identified by MS. (XLS 1469 kb)

Supplementary Data 2

List of all specific proteins identified by MS from bioNanog samples (XLS 52 kb)

Supplementary Data 3

A list of the key genes used in this study. (DOC 19 kb)

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Wang, J., Rao, S., Chu, J. et al. A protein interaction network for pluripotency of embryonic stem cells. Nature 444, 364–368 (2006). https://doi.org/10.1038/nature05284

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