Human Naive Pluripotent Stem Cells Model X Chromosome Dampening and X Inactivation.

Anna Sahakyan, Rachel Kim, Constantinos Chronis, Shan Sabri, Giancarlo Bonora, Thorold W Theunissen, Edward Kuoy, Justin Langerman, Amander T Clark, Rudolf Jaenisch, Kathrin Plath
Author Information
  1. Anna Sahakyan: Department of Biological Chemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA; Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA.
  2. Rachel Kim: Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, Los Angeles, CA 90095, USA.
  3. Constantinos Chronis: Department of Biological Chemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA.
  4. Shan Sabri: Department of Biological Chemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA; Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, Los Angeles, CA 90095, USA; Bioinformatics Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA 90095, USA.
  5. Giancarlo Bonora: Department of Biological Chemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA; Bioinformatics Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA 90095, USA.
  6. Thorold W Theunissen: Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA.
  7. Edward Kuoy: Department of Biological Chemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA.
  8. Justin Langerman: Department of Biological Chemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA.
  9. Amander T Clark: Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA; Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, Los Angeles, CA 90095, USA; Jonsson Comprehensive Cancer Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA; Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, Los Angeles, CA 90095, USA.
  10. Rudolf Jaenisch: Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.
  11. Kathrin Plath: Department of Biological Chemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA; Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA; Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, Los Angeles, CA 90095, USA; Jonsson Comprehensive Cancer Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA; Bioinformatics Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA 90095, USA. Electronic address: kplath@mednet.ucla.edu.

Abstract

Naive human embryonic stem cells (hESCs) can be derived from primed hESCs or directly from blastocysts, but their X chromosome state has remained unresolved. Here, we show that the inactive X chromosome (X) of primed hESCs was reactivated in naive culture conditions. Like cells of the blastocyst, the resulting naive cells contained two active X chromosomes with XIST expression and chromosome-wide transcriptional dampening and initiated XIST-mediated X inactivation upon differentiation. Both establishment of and exit from the naive state (differentiation) happened via an XIST-negative XX intermediate. Together, these findings identify a cell culture system for functionally exploring the two X chromosome dosage compensation processes in early human development: X dampening and X inactivation. However, remaining differences between naive hESCs and embryonic cells related to mono-allelic XIST expression and non-random X inactivation highlight the need for further culture improvement. As the naive state resets X abnormalities seen in primed hESCs, it may provide cells better suited for downstream applications.

Keywords

MeSH Term

Base Sequence
Blastocyst
Cell Differentiation
Cells, Cultured
Chromosomes, Human, X
DNA Methylation
Female
Histones
Human Embryonic Stem Cells
Humans
Lysine
Methylation
Pluripotent Stem Cells
RNA, Long Noncoding
X Chromosome Inactivation

Chemicals

Histones
RNA, Long Noncoding
XIST non-coding RNA
Lysine