The present invention provides rhesus monkey dickkopf-1 (rhDkk-1) and nucleotide sequences encoding it. Also provided herein are recombinant vectors, and recombinant hosts comprising rhDkk-1-encoding nucleotide sequences. Isolated rhDkk-1 can be used to screen and identify novel osteoanabolic compounds that stimulate bone formation for the treatment of osteoporosis or other disorders characterized by insufficient bone mass.