Overexpression of Snai3 suppresses lymphoid- and enhances myeloid-cell differentiation.

The altered expression of transcription factors in hematopoietic stem cells and their subsequent lineages can alter the development of lymphoid and myeloid lineages. The role of the transcriptional repressor Snai3 protein in the derivation of cells of the hemato-poietic system was investigated. Snai3 is expressed in terminal T-cell and myeloid lineages, therefore, we chose to determine if expressing Snai3 in the early stages of hematopoietic development would influence cell-lineage determination. Expression of Snai3 by retroviral transduction of hematopoietic stem cells using bone marrow chimera studies demonstrated a block in lymphoid-cell development and enhanced expansion of myeloid-lineage cells. Analysis of Snai3-expressing hematopoietic precursor cells showed normal numbers of immature cells, but a block in the development of cells committed to lymphoid lineages. These data indicate that the overexpression of Snai3 does alter bone marrow cell development and that the identification of genes whose expression is altered by the presence of Snai3 would aid in our understanding of these developmental pathways.