Aberrant processing of Mu1-induced mutant alleles

--Daniel Ortiz, Robert Gregerson and Judith Strommer

Mutant alleles of Adh1 and Sh1 produced by insertion of Mu1 transposable elements produce decreased levels of steady-state RNA, largely due to decreased levels of transcription. But in addition, at least some of the transcripts produced by these alleles are aberrantly processed, resulting in a family of polyadenlyated RNA species with altered splicing and polyadenylation sites. Some of the aberrant transcripts are unstable. The general pattern appears to fit that observed for other transposable element systems of maize (see esp. Simon and Starlinger, Mol. Gen. Genet., 1987).

The extent of aberrant processing appears to depend to some degree on genetic background, raising the possibility that polymorphic loci for components of the processing systems might be responsible for background-related differences in susceptibility to the mutational effects of Mu1 insertion (see preceding letter).

We are currently defining the splice junctions and polyadenylation sites used to produce aberrant transcripts of Adh1-Mu alleles and attempting to verify the association between genetic background and selection of processing sites.

Please Note: Notes submitted to the Maize Genetics Cooperation Newsletter may be cited only with consent of the authors

Return to the MNL 63 On-Line Index
Return to the Maize Newsletter Index
Return to the Maize Genome Database Page