Zeb2 (Sip1/Zfhx1b) is a member of the zinc-finger E-box - binding (ZEB) family of transcriptional repressors previously demonstrated to regulate epithelial-tomesenchymal transition (EMT) processes during embryogenesis and tumor progression. We found high Zeb2 mRNA expression levels in HSCs and hematopoietic progenitor cells (HPCs), and examined Zeb2 function in hematopoiesis through a conditional deletion approach using the Tie2-Cre and Vav-iCre recombination mouse lines. Detailed cellular analysis demonstrated that Zeb2 is dispensable for hematopoietic cluster and HSC formation in the aorta-gonadomesonephros region of the embryo, but is essential for normal HSC/HPC differentiation. In addition, Zeb2-deficient HSCs/HPCs fail to properly colonize the fetal liver and/or bone marrow and show enhanced adhesive properties associated with increased β1 integrin and Cxcr4 expression. Moreover, deletion of Zeb2 resulted in embryonic (Tie2-Cre) and perinatal (Vav-icre) lethality due to severe cephalic hemorrhaging and decreased levels of angiopoietin-1 and, subsequently, improper pericyte coverage of the cephalic vasculature. These results reveal essential roles for Zeb2 in embryonic hematopoiesis and are suggestive of a role for Zeb2 in hematopoietic-related pathologies in the adult.

doi.org/10.1182/blood-2010-08-300236, hdl.handle.net/1765/26262
Blood
Erasmus MC: University Medical Center Rotterdam

Goossens, S., Janzen, V., Bartunkova, S., Yokomizo, T., Drogat, B., Crisan, M., … Huylebroeck, D. (2011). The EMT regulator Zeb2/Sip1 is essential for murine embryonic hematopoietic stem/progenitor cell differentiation and mobilization. Blood, 117(21), 5620–5630. doi:10.1182/blood-2010-08-300236