Abstract

This study describes the creation and analysis of transgenic mice carrying a ribozyme or RNA enzyme that specifically targets the bovine a- lactalbumin (a-lac) mRNA transcript. Using a MMTV-LTR promoter-based construct, mammary specific high-level expression of a bovine a-lac- targeted ribozyme was obtained in three out of twelve lines of transgenic mice created. When crossed with mice transgenic for the bovine a-lac gene (0.4 mg of a-lac.ml-1 of milk), expression of the ribozyme resulted in a reduction in the levels of the target mRNA to 50% of that observed in the non-ribozyme transgenic littermate controls. This activity was specific to the bovine a-lac transcript as no reduction in the levels of the endogenous murine a-lac mRNA was observed. These results demonstrate the feasibility of ribozyme-mediated down-regulation of highly-expressed transcripts in transgenic animals.

PJ, L'Huillier, and JL Vilotte

Proceedings of the New Zealand Society of Animal Production, Volume 56, , 42-44, 1996