Integrating ribosomal promoter vectors that offer a choice of constitutive expression profiles in Leishmania donovani

• Six ribosomal RNA promoter (pRP) vectors were made for integration into the rRNA array.
• The pRP vectors provide five incrementally different expression profiles covering a 250-fold range.
• Different expression profiles were achieved by varying 5′- and 3′-UTR sequences.
• pRP vectors are available for making N- and C-terminal transgene fusions to GFP.
• The pRP vectors are specific for Leishmania donovani and closely related species.

We have designed a novel series of integrating ribosomal RNA promoter vectors with five incrementally different constitutive expression profiles, covering a 250-fold range. Differential expression was achieved by placing different combinations of synthetic or leishmanial DNA sequences upstream and downstream of the transgene coding sequence in order to modulate pre-mRNA processing efficiency and mRNA stability, respectively. All of the vectors have extensive multiple cloning sites, and versions are available for producing N- or C- terminal GFP fusions at each of the possible relative expression levels. In addition, the modular configuration of the vectors allows drug resistance cassettes and other components to be readily exchanged. In toto, these vectors should be useful additions to the toolkit available for molecular and genetic studies of Leishmania donovani.

Summary: Novel integrating ribosomal promoter vectors with incrementally different constitutive expression profiles are available for Leishmania donovani. Fluorescence intensity distributions from promastigotes expressing GFP from the six vectors are shown.Figure optionsDownload high-quality image (96 K)Download as PowerPoint slide