Abstract
Critical to homeostasis of blood cell production by hematopoietic stem/progenitor (HSC/P) cells is the regulation of HSC/P retention within the bone marrow microenvironment and migration between the bone marrow and the blood. Key extracellular regulatory elements for this process have been defined (cell-cell adhesion, growth factors, chemokines), but the mechanism by which HSC/P cells reconcile multiple external signals has not been elucidated. Rac and related small GTPases are candidates for this role and were studied in HSC/P deficient in Rac2, a hematopoietic cell-specific family member. Rac2 appears to be critical for HSC/P adhesion both in vitro and in vivo, whereas a compensatory increase in Cdc42 activation regulates HSC/P migration. This genetic analysis provides physiological evidence of cross-talk between GTPase proteins and suggests that a balance of these two GTPases controls HSC/P adhesion and mobilization in vivo.
Original language | English (US) |
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Pages (from-to) | 5614-5618 |
Number of pages | 5 |
Journal | Proceedings of the National Academy of Sciences of the United States of America |
Volume | 98 |
Issue number | 10 |
DOIs | |
State | Published - May 8 2001 |
Externally published | Yes |
ASJC Scopus subject areas
- General