Coding region-specific destabilization of mRNA transcripts attenuates expression from retroviral vectors containing class 1 aldehyde dehydrogenase cDNAs.

K D Bunting; M Webb; F Giorgianni; J Galipeau; R L Blakley; A J Townsend; B P Sorrentino

doi:10.1089/hum.1997.8.13-1531

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PubMed · 9322086

Coding region-specific destabilization of mRNA transcripts attenuates expression from retroviral vectors containing class 1 aldehyde dehydrogenase cDNAs.

K D Bunting·M Webb·F Giorgianni·J Galipeau·R L Blakley·A J Townsend·B P Sorrentino

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Abstract

Class 1 aldehyde dehydrogenases (ALDH-1) function as drug resistance gene products by catalyzing the irreversible conversion of aldophosphamide, an active metabolite of cyclophosphamide, to an inert compound. Because the dose-limiting toxicity of cyclophosphamide is myelosuppression, retrovirus-mediated transfer of ALDH-1 to bone marrow cells has been proposed as a protective strategy. Here we show that expression of ALDH-1 vectors was problematic due to low levels of ALDH-1 mRNA accumulation. A number of vectors containing several different ALDH-1 cDNAs were introduced into a variety of different cell lines either by transfection or transduction. Detectable ALDH-1 protein and enzyme activity was only seen in one transfected cell clone. Cells transduced with ALDH-1 retroviral vectors had no detectable protein expression and very low levels of ALDH-1 mRNA. Analogous vectors containing other drug resistance cDNAs led to much higher levels of steady-state mRNA. The mRNA half-life from ALDH-1 vectors was less than 2 hr suggesting that vector-derived mRNAs were destabilized by ALDH-1 coding sequences. These results suggest that methods which increase the stability of ALDH-1 mRNAs will be important for increased drug resistance in retrovirally transduced hematopoietic cells.

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Aldehyde Dehydrogenase Animals DNA, Complementary Drug Resistance Genetic Vectors Half-Life Mice RNA, Messenger Retroviridae Tetrahydrofolate Dehydrogenase Transduction, Genetic Transfection Tumor Cells, Cultured Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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K D Bunting, M Webb, F Giorgianni, J Galipeau, R L Blakley, A J Townsend, B P Sorrentino. 1997-09-01. Coding region-specific destabilization of mRNA transcripts attenuates expression from retroviral vectors containing class 1 aldehyde dehydrogenase cDNAs.. https://doi.org/10.1089/hum.1997.8.13-1531

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