title: Dysregulation of the Transforming Growth Factor β Pathway in Induced Pluripotent Stem Cells Generated from Patients with Diamond Blackfan Anemia.
abstract: Diamond Blackfan Anemia (DBA) is an inherited bone marrow failure syndrome with clinical features of red cell aplasia and variable developmental abnormalities. Most affected patients have heterozygous loss of function mutations in ribosomal protein genes but the pathogenic mechanism is still unknown. We generated induced pluripotent stem cells from DBA patients carrying RPS19 or RPL5 mutations. Transcriptome analysis revealed the striking dysregulation of the transforming growth factor β (TGFβ) signaling pathway in DBA lines. Expression of TGFβ target genes, such as TGFBI, BAMBI, COL3A1 and SERPINE1 was significantly increased in the DBA iPSCs. We quantified intermediates in canonical and non-canonical TGFβ pathways and observed a significant increase in the levels of the non-canonical pathway mediator p-JNK in the DBA iPSCs. Moreover, when the mutant cells were corrected by ectopic expression of WT RPS19 or RPL5, levels of p-JNK returned to normal. Surprisingly, nuclear levels of SMAD4, a mediator of canonical TGFβ signaling, were decreased in DBA cells due to increased proteolytic turnover. We also observed the up-regulation of TGFβ1R, TGFβ2, CDKN1A and SERPINE1 mRNA, and the significant decrease of GATA1 mRNA in the primitive multilineage progenitors. In summary our observations identify for the first time a dysregulation of the TGFβ pathway in the pathobiology of DBA.
authors.affiliation: Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America.
authors.forename: Jingping
authors.initials: J
authors.lastname: Ge
authors.affiliation: Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America.
authors.forename: Marisa
authors.initials: M
authors.lastname: Apicella
authors.affiliation: Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America.
authors.forename: Jason A
authors.initials: JA
authors.lastname: Mills
authors.affiliation: UPMC University Paris 06, UMR_S938, and Assistance Publique- Hôpitaux de Paris, Paris, France.
authors.forename: Loïc
authors.initials: L
authors.lastname: Garçon
authors.affiliation: Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America.
authors.forename: Deborah L
authors.initials: DL
authors.lastname: French
authors.affiliation: Department of Hematology, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America.
authors.forename: Mitchell J
authors.initials: MJ
authors.lastname: Weiss
authors.affiliation: Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America.
authors.forename: Monica
authors.initials: M
authors.lastname: Bessler
authors.affiliation: Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America.
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Mason
mesh_terms: D029503:Anemia, Diamond-Blackfan / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000378:metabolism; D005347:Fibroblasts / Q000378:metabolism; D050982:GATA1 Transcription Factor / Q000378:metabolism; D005786:Gene Expression Regulation; D006412:Hematopoietic Stem Cells / Q000166:cytology; D006579:Heterozygote; D006801:Humans; D057026:Induced Pluripotent Stem Cells / Q000166:cytology; D008958:Models, Molecular; D009154:Mutation; D017395:Plasminogen Activator Inhibitor 1 / Q000378:metabolism; D039904:Pluripotent Stem Cells / Q000166:cytology*; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D000077293:Receptor, Transforming Growth Factor-beta Type I; D000077294:Receptor, Transforming Growth Factor-beta Type II; D018125:Receptors, Transforming Growth Factor beta / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012269:Ribosomal Proteins / Q000235:genetics; D012270:Ribosomes / Q000378:metabolism; D015398:Signal Transduction; D051901:Smad4 Protein / Q000378:metabolism; D059467:Transcriptome; D053773:Transforming Growth Factor beta1 / Q000378:metabolism*; D015854:Up-Regulation
chemical_list: C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D050982:GATA1 Transcription Factor; C494688:GATA1 protein, human; D017395:Plasminogen Activator Inhibitor 1; D012333:RNA, Messenger; D018125:Receptors, Transforming Growth Factor beta; D012269:Ribosomal Proteins; C051321:SERPINE1 protein, human; C497796:SMAD4 protein, human; D051901:Smad4 Protein; C508960:TGFB1 protein, human; D053773:Transforming Growth Factor beta1; C549166:ribosomal protein L5, human; C040343:ribosomal protein S19; D017346:Protein Serine-Threonine Kinases; D000077293:Receptor, Transforming Growth Factor-beta Type I; D000077294:Receptor, Transforming Growth Factor-beta Type II