Signalling and transcriptional regulation of human primordial germ cell specification
type: CreativeWork
description: Primordial germ cells (PGCs), the precursors of gametes, are specified in early post-implantation human embryos, which are inaccessible for direct investigation. This process can however be modelled using human embryonic stem cells (hESCs) for in vitro derivation of human PGC-like cells (hPGCLCs). hESCs in conventional culture conditions have very low potential for germ cell fate; this increases significantly if the cells are first cultured in PGC competence-promoting media. To address how the PGC-competent state might be gained, I used a new computational tool – Branch-Recombinant Gaussian Processes (B-RGPs) – to identify potentially relevant pathways based on single-cell RNA sequencing of early human embryos, as well as gonadal PGCs and soma. I then tested these predictions experimentally by modulating the candidate signalling pathways in competent hESCs, followed by hPGCLC induction. I found that inhibition of FGF receptor (FGFR) or its downstream effectors (MEK and PI3K) enhanced competency for PGC fate. By contrast, premature MEK/ERK activation in hESCs resulted in aberrant expression of endoderm markers and loss of germ cell potential. Altogether the study showed that FGFR pathway is a negative regulator of cellular competence for human PGCLC fate. PGCLC specification from competent cells occurs in response to BMP signalling and is orchestrated by specific transcription factors (TFs). Emerging evidence points to many differences between TF networks in mouse and human PGCs. For example, SOX17 is essential for human germ cell fate, but is dispensable for mouse PGCs. On the other hand, a key pluripotency factor PRDM14 is crucial for mouse PGC specification, but its role in human PGC development is unclear. I designed genetic approaches to address PRDM14 involvement in human pluripotency versus PGC specification. To achieve inducible loss of function, I deleted endogenous PRDM14 in the background of doxycycline-repressible PRDM14 transgene expression. This approac…
abstract: Primordial germ cells (PGCs), the precursors of gametes, are specified in early post-implantation human embryos, which are inaccessible for direct investigation. This process can however be modelled using human embryonic stem cells (hESCs) for in vitro derivation of human PGC-like cells (hPGCLCs). hESCs in conventional culture conditions have very low potential for germ cell fate; this increases significantly if the cells are first cultured in PGC competence-promoting media. To address how the PGC-competent state might be gained, I used a new computational tool – Branch-Recombinant Gaussian Processes (B-RGPs) – to identify potentially relevant pathways based on single-cell RNA sequencing of early human embryos, as well as gonadal PGCs and soma. I then tested these predictions experimentally by modulating the candidate signalling pathways in competent hESCs, followed by hPGCLC induction. I found that inhibition of FGF receptor (FGFR) or its downstream effectors (MEK and PI3K) enhanced competency for PGC fate. By contrast, premature MEK/ERK activation in hESCs resulted in aberrant expression of endoderm markers and loss of germ cell potential. Altogether the study showed that FGFR pathway is a negative regulator of cellular competence for human PGCLC fate. PGCLC specification from competent cells occurs in response to BMP signalling and is orchestrated by specific transcription factors (TFs). Emerging evidence points to many differences between TF networks in mouse and human PGCs. For example, SOX17 is essential for human germ cell fate, but is dispensable for mouse PGCs. On the other hand, a key pluripotency factor PRDM14 is crucial for mouse PGC specification, but its role in human PGC development is unclear. I designed genetic approaches to address PRDM14 involvement in human pluripotency versus PGC specification. To achieve inducible loss of function, I deleted endogenous PRDM14 in the background of doxycycline-repressible PRDM14 transgene expression. This approac…
author: Sybirna, Anastasiya
language: en
keywords: human primordial germ cells (hPGCs), embryonic stem cells, PRDM14, auxin-inducible degron (AID), jasmonate-inducible degron, developmental competence, human development, FGFR signalling, human primordial germ cell-like cells (hPGCLCs)
license: https://apollo8-f-pro.lib.cam.ac.uk/bitstreams/8914b59d-78bf-469f-a9c8-e8692cfd7989/download
license: https://www.rioxx.net/licenses/all-rights-reserved/
date published: 2020-04-25
date modified: 2026-07-22T22:24:21Z
provider: Cambridge University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Cambridge

PropertyValue
property ID: DOI
value: 10.17863/CAM.45149