Klf5 controls bone marrow homing of stem cells and progenitors through Rab5-mediated membrane Beta1/Beta2-integrin expression

ABSTRACT: The Kruppel-like factor 5 (Klf5) regulates pluripotent stem cell self-renewal but its role in somatic stem cells is unknown. Klf5 deficient hematopoietic stem cells and progenitors (HSC/P) fail to engraft after transplantation. This HSC/P defect was associated with impaired bone marrow (BM) homing and lodging and decreased retention in BM. The Klf5Δ/Δ HSC/P homing defect associated with decreased adhesion to fibronectin and expression of membrane-bound β1/β2-integrins. In vivo inducible gain-of-function of Klf5 in HSC translated into increased HSC/P adhesion. The expression of Rab5 family members, mediators of β1/β2-integrin recycling in the early endosome, was decreased in Klf5Δ/Δ HSC/P. Klf5 binds directly to the promoter of Rab5a/b and overexpression of Rab5b rescued the expression of activated β1/β2-integrins, adhesion and BM homing of Klf5Δ/Δ HSC/P. Altogether, these data indicate that Klf5 is indispensable for adhesion, homing, lodging and retention of HSC/P in the BM through Rab5-dependent post-translational regulation of Beta1/Beta2 integrins. Differential gene expression analyses was performed with Affymetrix GeneChip Mouse 1.0 ST assay. LSK cells from KLF-/- (n=4) and wt (n=5), bred on a C57BL/6 background, was analyzed for differential gene expression using GeneSpring GX11 using student's T-test.

ORGANISM(S): Mus musculus

SUBMITTER: Jose Cancelas 

PROVIDER: E-GEOD-43806 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress