Abstract: The invention provides osteoactivin proteins and nucleic acid molecules that encode the same, as well as biologically functional expression vectors containing nucleic acid molecules encoding osteoactivin proteins, and antibodies specific for osteoactivin proteins. The invention also provides therapeutic and diagnostic compositions and methods for utilizing the proteins, antibodies, nucleic acids, and vectors of the invention, for example, to modulate bone formation.

Abstract: Agents for promoting bone deposition and growth in a mammalian subject. The agents are O-glycosylated and non-glycosylated peptides that are derived from vitamin D binding protein, collectively referred to hereinafter as “DBP” peptides. The DBP peptides are from 3 to 18, preferably from 4 to 14 amino acids in length and comprise a sequence which is at least 80% identical, preferably at least 90% identical to the amino acid sequence of a fragment contained within domain III of DBP. Methods for promoting bone deposition in a subject in need of the same are also provided. The methods comprise administering to the subject a therapeutically effective quantity of an agent selected from the group consisting of an activated form of vitamin D binding protein referred to hereinafter as “ADBP”, one or more DBP peptides, and combinations thereof. The agents may be administered locally or systemically.

Abstract: The invention provides osteoactivin proteins and nucleic acid molecules that encode the same, as well as biologically functional expression vectors containing nucleic acid molecules encoding osteoactivin proteins, and antibodies specific for osteoactivin proteins. The invention also provides therapeutic and diagnostic compositions and methods for utilizing the proteins, antibodies, nucleic acids, and vectors of the invention, for example, to modulate bone formation.