Commercial use of the human cytomaglovirus promoter/enhancer has been patented on behalf of B. Fleckenstein and W. Schaffner by the Beringwerke. Interested parties should contact the patent holders before planning a commercial application. A shuttle vector for transient expression of cDNA inserts in mammalian cells. Constructed by inserting a 0.62 kb SmaI/EcoRI fragment from pMThGH containing part of exon 5 and 3′ untranslated regions of the human growth hormone gene into the SmaI/EcoRI sites of pAVE1 (ATCC 37838). Restriction digests of the clone give the following sizes (kb): HindIII-3.5; BamHI–3.5; EcoRI–3.5; SmaI–3.5. (ATCC staff) Medium is 1227 LB plus ampicillin. Hosts: E.coli HB101, vertebrate cells, E.coli, monkey COS-7