Point mutations in the PDX1 transactivation domain impair human β-cell development and function
| Autor: | Filippo M. Cernilogar, Gunnar Schotta, Julia Beckenbauer, Ingo Burtscher, Anika Böttcher, Ansarullah, Martin Irmler, Thomas Meitinger, Xianming Wang, Johanna Siehler, Harald Staiger, Michael Sterr, Johannes Beckers, Mostafa Bakhti, Heiko Lickert, Hans-Ulrich Häring, Christopher V.E. Wright |
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| Rok vydání: | 2019 |
| Předmět: |
Adult
Male 0301 basic medicine lcsh:Internal medicine endocrine system Lineage (genetic) endocrine system diseases β-Cell differentiation 030209 endocrinology & metabolism Biology medicine.disease_cause digestive system Cell Line 03 medical and health sciences Transactivation 0302 clinical medicine Protein Domains Loss of Function Mutation Insulin-Secreting Cells Pdx1 Transactivation Domain Beta-cell Differentiation Insulin Secretion Pdx1-bound Genes Diabetes Mellitus medicine Humans Point Mutation Missense mutation lcsh:RC31-1245 Molecular Biology Gene Homeodomain Proteins MEG3 PDX1 Mutation Transactivation domain Insulin secretion Point mutation Cell Differentiation Cell Biology Molecular biology ddc 3. Good health 030104 developmental biology Trans-Activators Original Article Female RNA Long Noncoding Carboxylic Ester Hydrolases PDX1-Bound genes Transcription Factors |
| Zdroj: | Molecular Metabolism Molecular Metabolism, Vol 24, Iss, Pp 80-97 (2019) Mol. Metab. 24, 80-97 (2019) |
| ISSN: | 2212-8778 |
| DOI: | 10.1016/j.molmet.2019.03.006 |
| Popis: | Objective Hundreds of missense mutations in the coding region of PDX1 exist; however, if these mutations predispose to diabetes mellitus is unknown. Methods In this study, we screened a large cohort of subjects with increased risk for diabetes and identified two subjects with impaired glucose tolerance carrying common, heterozygous, missense mutations in the PDX1 coding region leading to single amino acid exchanges (P33T, C18R) in its transactivation domain. We generated iPSCs from patients with heterozygous PDX1P33T/+, PDX1C18R/+ mutations and engineered isogenic cell lines carrying homozygous PDX1P33T/P33T, PDX1C18R/C18R mutations and a heterozygous PDX1 loss-of-function mutation (PDX1+/−). Results Using an in vitro β-cell differentiation protocol, we demonstrated that both, heterozygous PDX1P33T/+, PDX1C18R/+ and homozygous PDX1P33T/P33T, PDX1C18R/C18R mutations impair β-cell differentiation and function. Furthermore, PDX1+/− and PDX1P33T/P33T mutations reduced differentiation efficiency of pancreatic progenitors (PPs), due to downregulation of PDX1-bound genes, including transcription factors MNX1 and PDX1 as well as insulin resistance gene CES1. Additionally, both PDX1P33T/+ and PDX1P33T/P33T mutations in PPs reduced the expression of PDX1-bound genes including the long-noncoding RNA, MEG3 and the imprinted gene NNAT, both involved in insulin synthesis and secretion. Conclusions Our results reveal mechanistic details of how common coding mutations in PDX1 impair human pancreatic endocrine lineage formation and β-cell function and contribute to the predisposition for diabetes. Highlights • Missense mutations in the transactivation domain reduce PDX1 target gene expression. • Lack of PDX1 target gene activation impairs both β-cell development and function. • Common PDX1 coding mutations likely predispose for diabetes. |
| Databáze: | OpenAIRE |
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