The present invention relates to the field of therapeutic use of proteins, genes and cells. More specifically the invention relates to therapy based on the biological function of a secreted therapeutic protein, NsG33, in particular for the treatment of disorders of the nervous system. NsG33 is a nerve survival and growth factor with antiapoptotic effects on a cell line with neuronal potential and with neuroprotective and/or neurogenesis effects on a neural precursor cell line and on primary striatal cultures. The invention also relates to novel bioactive NsG33 polypeptide fragments and the corresponding encoding DNA sequences.
