The invention can be summarized as follows. There is provided methods andcompositions for modulating proliferation and/or lineage commitment of stemcells by modulating the Wnt signalling pathways. Modulators of the Wntsignalling pathways and screening methods to identify modulators are alsoprovided. The methods of the invention may be conducted in vitro or in vivo toinduce or inhibit stem cell proliferation and/or lineage commitment, and areparticularly useful for in vivo stimulation of proliferation and/or lineagecommitment of resident stem cells in a tissue.
