Deciphering the role of BMP4 signalling and gene regulation in the specification of human liver progenitor cells

Early hepatic specification and organogenesis can be modelled in vitro using human induced pluripotent stem cells (hiPSCs). These models apply differentiation protocols to direct hiPSCs through all the key developmental stages to accurately reflect in vivo development. Bone morphogenetic protein (BM...

Full description

Bibliographic Details
Main Author: Durczak, Paulina Maria
Format: Thesis (University of Nottingham only)
Language:English
Published: 2023
Subjects:
Online Access:https://eprints.nottingham.ac.uk/75725/
_version_ 1848800881541120000
author Durczak, Paulina Maria
author_facet Durczak, Paulina Maria
author_sort Durczak, Paulina Maria
building Nottingham Research Data Repository
collection Online Access
description Early hepatic specification and organogenesis can be modelled in vitro using human induced pluripotent stem cells (hiPSCs). These models apply differentiation protocols to direct hiPSCs through all the key developmental stages to accurately reflect in vivo development. Bone morphogenetic protein (BMP) and fibroblast growth factor (FGF) signalling are crucial for the specification of hepatic progenitors during early liver development. While the signalling cascades of these two morphogens are well characterized, the mechanisms by which they promote hepatic cell fate choice and hepatic gene expression in anterior foregut endoderm (FE) cells is not very well understood. In this project, we characterize hiPSCs-based model of early liver development and apply it to understand the role of BMP signalling in hepatic specification. We confirm that BMP4 signalling is also necessary for liver progenitor cells (LPCs) specification from FE during hiPSCs differentiation. Using RNA sequencing (RNA seq.) we examine transcriptome changes induced by BMP4 during the transition from FE to LPC stage. Overrepresentation analysis (ORA) and gene set enrichment analysis (GSEA) analysis revealed early activation of hepatocyte-specific functions such as lipid and protein homeostasis, haem metabolism or coagulation, while at the same time, cell adhesion and locomotion related genes are downregulated indicating preparation for cell migration out of the forming liver bud. We also notice upregulation of all four FGF receptors upon BMP signalling indicating at possible cross talk between the two pathways. The RNA seq. also detected a number of BMP4 upregulated transcription factors (TFs), several of these TFs are known for their roles in multiple developmental processes. Among them TBX3, previously reported to have a role in hepatic specification in mice, and two other TBX family members: TBX2 and TBX20. As a preliminary screen, we used a published, optimized protocol for creating inducible knockdown hiPSC lines to assess the importance of TBX and other TFs for the process of LPC specification. Double knockdown of TBX3 and TBX20 TFs significantly disrupted the hepatic induction process as shown by decreased expression of early hepatic genes such as TTR, AFP, AAT and ALB. Further studies are necessary to confirm and further characterize the role of TBX TFs for hepatic specification. Our study demonstrates that application of hiPSCs derived models for the study of development can aid the understanding of molecular mechanisms driving early liver specification and improve our understanding of human embryology and organogenesis. This knowledge can also be used to created more efficient differentiation platforms that can yield more mature, functional and clinically relevant populations of hiPSC-derived hepatocytes.
first_indexed 2025-11-14T20:58:36Z
format Thesis (University of Nottingham only)
id nottingham-75725
institution University of Nottingham Malaysia Campus
institution_category Local University
language English
last_indexed 2025-11-14T20:58:36Z
publishDate 2023
recordtype eprints
repository_type Digital Repository
spelling nottingham-757252023-12-13T04:40:14Z https://eprints.nottingham.ac.uk/75725/ Deciphering the role of BMP4 signalling and gene regulation in the specification of human liver progenitor cells Durczak, Paulina Maria Early hepatic specification and organogenesis can be modelled in vitro using human induced pluripotent stem cells (hiPSCs). These models apply differentiation protocols to direct hiPSCs through all the key developmental stages to accurately reflect in vivo development. Bone morphogenetic protein (BMP) and fibroblast growth factor (FGF) signalling are crucial for the specification of hepatic progenitors during early liver development. While the signalling cascades of these two morphogens are well characterized, the mechanisms by which they promote hepatic cell fate choice and hepatic gene expression in anterior foregut endoderm (FE) cells is not very well understood. In this project, we characterize hiPSCs-based model of early liver development and apply it to understand the role of BMP signalling in hepatic specification. We confirm that BMP4 signalling is also necessary for liver progenitor cells (LPCs) specification from FE during hiPSCs differentiation. Using RNA sequencing (RNA seq.) we examine transcriptome changes induced by BMP4 during the transition from FE to LPC stage. Overrepresentation analysis (ORA) and gene set enrichment analysis (GSEA) analysis revealed early activation of hepatocyte-specific functions such as lipid and protein homeostasis, haem metabolism or coagulation, while at the same time, cell adhesion and locomotion related genes are downregulated indicating preparation for cell migration out of the forming liver bud. We also notice upregulation of all four FGF receptors upon BMP signalling indicating at possible cross talk between the two pathways. The RNA seq. also detected a number of BMP4 upregulated transcription factors (TFs), several of these TFs are known for their roles in multiple developmental processes. Among them TBX3, previously reported to have a role in hepatic specification in mice, and two other TBX family members: TBX2 and TBX20. As a preliminary screen, we used a published, optimized protocol for creating inducible knockdown hiPSC lines to assess the importance of TBX and other TFs for the process of LPC specification. Double knockdown of TBX3 and TBX20 TFs significantly disrupted the hepatic induction process as shown by decreased expression of early hepatic genes such as TTR, AFP, AAT and ALB. Further studies are necessary to confirm and further characterize the role of TBX TFs for hepatic specification. Our study demonstrates that application of hiPSCs derived models for the study of development can aid the understanding of molecular mechanisms driving early liver specification and improve our understanding of human embryology and organogenesis. This knowledge can also be used to created more efficient differentiation platforms that can yield more mature, functional and clinically relevant populations of hiPSC-derived hepatocytes. 2023-12-13 Thesis (University of Nottingham only) NonPeerReviewed application/pdf en cc_by https://eprints.nottingham.ac.uk/75725/1/Paulina_Maria_Durczak_thesis_corrected.pdf Durczak, Paulina Maria (2023) Deciphering the role of BMP4 signalling and gene regulation in the specification of human liver progenitor cells. PhD thesis, University of Nottingham. Hepatic specification; Organogenesis; Human induced pluripotent stem cells; Hepatic progenitors; Liver development; Transcription factors; Hepatocytes
spellingShingle Hepatic specification; Organogenesis; Human induced pluripotent stem cells; Hepatic progenitors; Liver development; Transcription factors; Hepatocytes
Durczak, Paulina Maria
Deciphering the role of BMP4 signalling and gene regulation in the specification of human liver progenitor cells
title Deciphering the role of BMP4 signalling and gene regulation in the specification of human liver progenitor cells
title_full Deciphering the role of BMP4 signalling and gene regulation in the specification of human liver progenitor cells
title_fullStr Deciphering the role of BMP4 signalling and gene regulation in the specification of human liver progenitor cells
title_full_unstemmed Deciphering the role of BMP4 signalling and gene regulation in the specification of human liver progenitor cells
title_short Deciphering the role of BMP4 signalling and gene regulation in the specification of human liver progenitor cells
title_sort deciphering the role of bmp4 signalling and gene regulation in the specification of human liver progenitor cells
topic Hepatic specification; Organogenesis; Human induced pluripotent stem cells; Hepatic progenitors; Liver development; Transcription factors; Hepatocytes
url https://eprints.nottingham.ac.uk/75725/