Human germline cells are essential for human reproduction as only these cells are capable of differentiating into gametes and transmitting DNA from parent to child. The pioneering cells of the human germline begin to form during prenatal life when a small number of embryonic cells are set aside around the time of embryo implantation and gastrulation in a process known as human primordial germ cell (hPGC) specification. This critical event in human germline cell development has a tremendous impact on an individual's future reproductive health as a failure in hPGC specification causes certain infertility. In this competitive renewal, the goal is to increase our fundamental knowledge on the cell and molecular basis of hPGC specification. Based on experimental results in the previous funding period, we aim to use human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs) and the differentiation of hPGC-like cells (hPGCLCs) to achieve this goal. The overall hypothesis is that non-rodent and human-specific molecular events have evolved to regulate hPGC specification. Given that the focus of this grant is largely on regions of the genome that are uniquely human, this project is perfectly suited to the use of human cell-based models.
In aim 1, the hypothesis to be addressed is that TFAP2C-bound human-specific retrotransposons regulate hPGC specification.
In aim 2, the hypothesis to be addressed is that the expression of TFAP2C bound retrotransposons are regulated by targeted changes to the epigenome during hPGCLC differentiation. In the third aim, we will evaluate the relationship between TFAP2C and SOX17 in hPGC specification, with the hypothesis that TFAP2C functions upstream of SOX17 in a lineage primed hPGC progenitor to regulate specification of hPGCs. In summary, this competitive renewal builds upon success from the first funding period to contribute essential knowledge on the identification of new loci in the human genome that have evolved to regulate the specification and identity of hPGCs.

Public Health Relevance

This basic science research application is designed to increase our understanding of the cell and molecular mechanisms involved in human PGC (hPGC) specification using human pluripotent stem cells as a model. Outcomes from this project will involve acquiring the basic science knowledge necessary to understand one of the foundational events in human reproduction, the establishment of human germline cells in the embryo.

Agency
National Institute of Health (NIH)
Institute
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Type
Research Project (R01)
Project #
2R01HD079546-06A1
Application #
10050468
Study Section
Cellular, Molecular and Integrative Reproduction Study Section (CMIR)
Program Officer
Ravindranath, Neelakanta
Project Start
2014-12-20
Project End
2025-04-30
Budget Start
2020-08-01
Budget End
2021-04-30
Support Year
6
Fiscal Year
2020
Total Cost
Indirect Cost
Name
University of California Los Angeles
Department
Biochemistry
Type
Schools of Arts and Sciences
DUNS #
092530369
City
Los Angeles
State
CA
Country
United States
Zip Code
90095
Tao, Yu; Yen, Ming-Ren; Chitiashvili, Tsotne et al. (2018) TRIM28-Regulated Transposon Repression Is Required for Human Germline Competency and Not Primed or Naive Human Pluripotency. Stem Cell Reports 10:243-256
Gell, Joanna J; Zhao, Jasmine; Chen, Di et al. (2018) PRDM14 is expressed in germ cell tumors with constitutive overexpression altering human germline differentiation and proliferation. Stem Cell Res 27:46-56
Pastor, William A; Liu, Wanlu; Chen, Di et al. (2018) TFAP2C regulates transcription in human naive pluripotency by opening enhancers. Nat Cell Biol 20:553-564
Sahakyan, Anna; Kim, Rachel; Chronis, Constantinos et al. (2017) Human Naive Pluripotent Stem Cells Model X Chromosome Dampening and X Inactivation. Cell Stem Cell 20:87-101
O'Brien, Carmel M; Chy, Hun S; Zhou, Qi et al. (2017) New Monoclonal Antibodies to Defined Cell Surface Proteins on Human Pluripotent Stem Cells. Stem Cells 35:626-640
Chen, Di; Liu, Wanlu; Lukianchikov, Anastasia et al. (2017) Germline competency of human embryonic stem cells depends on eomesodermin. Biol Reprod 97:850-861
Clark, Amander T; Gkountela, Sofia; Chen, Di et al. (2017) Primate Primordial Germ Cells Acquire Transplantation Potential by Carnegie Stage 23. Stem Cell Reports 9:329-341
Chen, Di; Gell, Joanna J; Tao, Yu et al. (2017) Modeling human infertility with pluripotent stem cells. Stem Cell Res 21:187-192
Patel, Sanjeet; Bonora, Giancarlo; Sahakyan, Anna et al. (2017) Human Embryonic Stem Cells Do Not Change Their X Inactivation Status during Differentiation. Cell Rep 18:54-67
Pastor, William A; Chen, Di; Liu, Wanlu et al. (2016) Naive Human Pluripotent Cells Feature a Methylation Landscape Devoid of Blastocyst or Germline Memory. Cell Stem Cell 18:323-329

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