1. Twist-1, a novel regulator of hematopoietic stem cell self-renewal and myeloid lineage development.
- Author
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Dong CY, Liu XY, Wang N, Wang LN, Yang BX, Ren Q, Liang HY, and Ma XT
- Subjects
- Animals, Cell Division, Hematopoiesis genetics, Hematopoietic Stem Cells metabolism, Mice, Inbred C57BL, Myeloid Cells metabolism, Cell Differentiation physiology, Cell Lineage genetics, Cell Self Renewal, Hematopoiesis physiology, Hematopoietic Stem Cells cytology, Myeloid Cells cytology, Nuclear Proteins metabolism, Twist-Related Protein 1 metabolism
- Abstract
Transcription factor Twist-1 plays essential roles in specification and differentiation of mesoderm-derived tissues. Growing evidences now link Twist-1 to the acquisition of stem-cell-like properties. However, the role of Twist-1 in hematopoietic stem cell (HSC) remains largely uncharacterized. We report that Twist-1 is more highly expressed in murine HSC and its expression declines with differentiation. To investigate Twist-1 gene function, retroviral-mediated overexpression or removal experiments are performed. Competitive repopulation studies demonstrate that enforced expression of Twist-1 in HSC-enriched Lin(-) c-Kit(+) Sca-1(+) (LKS) cells results in an increase in the size of the G(0) population, and in their reconstitution ability after the first and a second transplantation. Conversely, removal of Twist-1 in LKS cells impairs their ability to repopulate. In addition, increased Twist-1 expression causes a shift toward production of myeloid cells. Twist-1 transduction in LKS cells activates myeloid lineage-determining factors PU.1 and GATA-1 and downregulates lymphoid factor GATA-3 in vitro, suggesting that Twist-1-mediated myeloid skewing occurs in hematopoietic stem and progenitor cells (HSPCs). These findings indicate that Twist-1 is not only involved in the maintenance of HSC dormancy and self-renewal capacity but also implicated in the myeloid lineage fate choice of HSPCs. Exploration of the underlying mechanisms reveals that Runx1/c-Mpl/Tie2 regulatory pathway could possibly account for the observed effects caused by Twist-1 overexpression. Our study provides the first evidence supporting a role for Twist-1 in hematopoiesis., (© 2014 AlphaMed Press.)
- Published
- 2014
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