TY - JOUR
T1 - Induction of hyperproliferative fetal megakaryopoiesis by an N-terminally truncated GATA1 mutant
AU - Shimizu, Ritsuko
AU - Kobayashi, Eri
AU - Engel, James Douglas
AU - Yamamoto, Masayuki
PY - 2009
Y1 - 2009
N2 - Two GATA1-related leukemias have been described: one is an erythroleukemia that develops in mice as a consequence of diminished expression of wild-type GATA1, whereas the other is an acute megakaryoblastic leukemia (AMKL) that arises in Down syndrome children as a consequence of somatic N-terminal truncation (ΔNT) of GATA1. We discovered that mice expressing the shortened GATA1 protein (ΔNTR mice) phenocopies the human transient myeloproliferative disorder (TMD) that precedes AMKL in Down syndrome children. In perinatal livers of the ΔNTR mutant mice, immature megakaryocytes accumulate massively, and this fraction contains cells that form hyperproliferative megakaryocytic colonies. Furthermore, showing good agreement with the clinical course of TMD in humans, ΔNTR mutant mice undergo spontaneous resolution from the massive megakaryocyte accumulation concomitant with the switch of hematopoietic microenvironment from liver to bone marrow/spleen. These results thus demonstrate that expression of the GATA1/Gata1 N-terminal deletion mutant per se induces hyperproliferative fetal megakaryopoiesis. This mouse model serves as an important means to clarify how impaired GATA1 function contributes to the multi-step leukemogenesis.
AB - Two GATA1-related leukemias have been described: one is an erythroleukemia that develops in mice as a consequence of diminished expression of wild-type GATA1, whereas the other is an acute megakaryoblastic leukemia (AMKL) that arises in Down syndrome children as a consequence of somatic N-terminal truncation (ΔNT) of GATA1. We discovered that mice expressing the shortened GATA1 protein (ΔNTR mice) phenocopies the human transient myeloproliferative disorder (TMD) that precedes AMKL in Down syndrome children. In perinatal livers of the ΔNTR mutant mice, immature megakaryocytes accumulate massively, and this fraction contains cells that form hyperproliferative megakaryocytic colonies. Furthermore, showing good agreement with the clinical course of TMD in humans, ΔNTR mutant mice undergo spontaneous resolution from the massive megakaryocyte accumulation concomitant with the switch of hematopoietic microenvironment from liver to bone marrow/spleen. These results thus demonstrate that expression of the GATA1/Gata1 N-terminal deletion mutant per se induces hyperproliferative fetal megakaryopoiesis. This mouse model serves as an important means to clarify how impaired GATA1 function contributes to the multi-step leukemogenesis.
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U2 - 10.1111/j.1365-2443.2009.01338.x
DO - 10.1111/j.1365-2443.2009.01338.x
M3 - Article
C2 - 19682090
AN - SCOPUS:69849088569
VL - 14
SP - 1119
EP - 1131
JO - Genes to Cells
JF - Genes to Cells
SN - 1356-9597
IS - 9
ER -