| abstract |
Isolated nucleic acid molecules encoding novel members of the p62 family of polypeptides which include, in preferred embodiment, an SH2 binding domain and a ubiquitin binding domain are described. Also disclosed are novel members of the p160 family of polypeptides. The p62 polypeptides and the p160 polypeptides of the invention are capable of modulating leukocyte activity, e.g., by stimulating a B cell response, including B cell proliferation, B cell aggregation, B cell differentiation, B cell survival, and/or stimulating a T cell response, e.g., T cell proliferation, T cell aggregation, T cell differentiation, and T cell survival, are disclosed. The p62 polypeptides and the p160 polypeptides of the invention are also capable of modulating ubiquitin-mediated degradation of cellular proteins. In addition to isolated nucleic acids molecules, antisense nucleic acid molecules, recombinant expression vectors containing a nucleic acid molecule of the invention, host cells into which the expression vectors have been introduced are also described. The invention further provides isolated p62 polypeptides and isolated p160 polypeptides, fusion polypeptides and active fragments thereof. Diagnostic and therapeutic methods utilizing compositions of the invention are also provided. |