Vectors having replication, immunogenicity and/or pathogenicity under stress promoter regulation and use thereof

The present invention relates to modified vectors, e.g. plasmids, viruses or microbia sucsh as yeast or bacteria, wherein the replication, immunogenicity and/or pathogenicity is placed under the control of at least one stress gene regulating element. In preferred embodiments, these modified vectors are used for gene therapy, in vaccines, or for functional genomic screening.