Background: GATA1 is an essential transcription factor for both polyploidization and megakaryocyte (MK) differentiation. The polyploidization defect observed in GATA1 variant carriers is not well understood.
Objective: To extensively phenotype two pedigrees displaying different variants in the GATA1 gene and determine if GATA1 controls MYH10 expression levels, a key modulator of MK polyploidization.
Method: A total of 146 unrelated propositi with constitutional thrombocytopenia were screened on a multigene panel. We described the genotype-phenotype correlation in GATA1 variant carriers and investigated the effect of these novel variants on MYH10 transcription using luciferase constructs.
Results: The clinical profile associated with the p.L268M variant localized in the C terminal zinc finger was unusual in that the patient displayed bleeding and severe platelet aggregation defects without early-onset thrombocytopenia. p.N206I localized in the N terminal zinc finger was associated, on the other hand, with severe thrombocytopenia (15G/L) in early life. High MYH10 levels were evidenced in platelets of GATA1 variant carriers. Analysis of MKs anti-GATA1 chromatin immunoprecipitation-sequencing data revealed two GATA1 binding sites, located in the 3' untranslated region and in intron 8 of the MYH10 gene. Luciferase reporter assays showed their respective role in the regulation of MYH10 gene expression. Both GATA1 variants significantly alter intron 8 driven MYH10 transcription.
Conclusion: The discovery of an association between MYH10 and GATA1 is a novel one. Overall, this study suggests that impaired MYH10 silencing via an intronic regulatory element is the most likely cause of GATA1-related polyploidization defect.
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http://dx.doi.org/10.1111/jth.15412 | DOI Listing |
Haematologica
January 2025
Aix Marseille Univ, INSERM, INRAe, C2VN, Marseille.
Germline variants of FLI1, essential for megakaryopoiesis, are linked to bleeding disorders, platelet aggregation defects and mild thrombocytopenia. However, the mechanisms behind these abnormalities remain unclear. This study aims to elucidate the impact of FLI1 variants on human megakaryocytes and platelets.
View Article and Find Full Text PDFHeliyon
September 2024
Division of Clinical Microscopy, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand.
Transfus Med Hemother
August 2024
Division of Hematology and Transfusion Medicine, Department of Laboratory Medicine, Lund University, Lund, Sweden.
Introduction: With over 360 blood group antigens in systems recognized, there are antigens, such as RhD, which demonstrate a quantitative reduction in antigen expression due to nucleotide variants in the non-coding region of the gene that result in aberrant splicing or a regulatory mechanism. This study aimed to evaluate bioinformatically predicted GATA1-binding regulatory motifs in the gene for samples presenting with weak or apparently negative RhD antigen expression but showing normal exons.
Methods: Publicly available open chromatin region data were overlayed with GATA1 motif candidates in .
BMC Med Genomics
July 2024
Department of Reproductive Medicine, Affiliated Shenzhen Maternity & Child Healthcare Hospital, Southern Medical University (Shenzhen Maternity & Child Healthcare Hospital), Shenzhen, Guangdong, China.
Exp Hematol
September 2024
Wisconsin Blood Cancer Research Institute, Department of Cell and Regenerative Biology, Carbone Cancer Center, University of Wisconsin School of Medicine and Public Health, Madison, WI. Electronic address:
Transcriptional mechanisms establish and maintain complex genetic and protein networks to control cell state transitions. The hematopoietic transcription factor GATA1 is a master regulator of erythropoiesis and megakaryopoiesis, and human GATA1 genetic variants cause anemia and megakaryoblastic leukemia. Multiomic analyses revealed that GATA1 controls expression of transporters and metabolic enzymes that dictate intracellular levels of endogenous small molecules, including heme, metal ions, and sphingolipids.
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