Osteoblasts selleck AR-12 expressing the homophilic adhesion molecule N-cadherin form a hematopoietic stem cell (HSC) niche. For that reason, we examined how N-cadherin expression in HSCs relates to their function. We located that bone marrow (BM) cells remarkably expressing N-cadherin (N-cadherin hi) are certainly not stem cells, being largely devoid of the Lineage(-)Scal(+)cKit(+) population and unable to reconstitute hematopoietic lineages in irradiated recipient mice. As a substitute, long-term HSCs form distinct populations expressing N-cadherin at intermediate (N-cadherin(int)) or low (N-cadherin(lo)) levels. The minority N-cadherin(lo) population Microtubule Associated can robustly reconstitute the hematopoietic method, express genes that could prime them to mobilize, and predominate between HSCs mobilized from BM to spleen. The larger N-cadherin(int) population performs poorly in reconstitution assays when freshly isolated but improves in response to overnight in vitro culture. Their expression profile and lower cell-cycle entry price propose N-cadherinint cells are currently being held in reserve. Therefore, differential N-cadherin expression reflects practical distinctions concerning two HSC subpopulations.