Yeast lariat debranching enzyme. Substrate and sequence specificity.

K Nam; R H Hudson; K B Chapman; K Ganeshan; M J Damha; J D Boeke

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PubMed · 7519612

Yeast lariat debranching enzyme. Substrate and sequence specificity.

K Nam·R H Hudson·K B Chapman·K Ganeshan·M J Damha·J D Boeke

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Abstract

Yeast RNA lariat debranching enzyme has been purified to near homogeneity using a bacterial overproducer of the enzyme. The enzyme is capable of digesting a variety of branched nucleic acid substrates, including group II intron lariats, multicopy single-stranded DNAs (msDNAs), and a variety of synthetic branched RNAs. A trinucleotide release assay using radiolabeled msDNA substrates was developed and used to determine the basic biochemical parameters for the enzyme. The debranching enzyme shows a strong preference for purines at the 2'-position in both msDNA and synthetic branched RNA substrates, in accord with the structure of its native substrate, which always has a 2'-G residue. The use of small synthetic branched RNA substrates will allow systematic mechanistic and structural studies of this unique enzyme.

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Base Sequence DNA, Single-Stranded Electrophoresis, Polyacrylamide Gel Introns Molecular Sequence Data Nucleotides RNA RNA Nucleotidyltransferases RNA Splicing Saccharomyces cerevisiae Substrate Specificity Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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K Nam, R H Hudson, K B Chapman, K Ganeshan, M J Damha, J D Boeke. 1994-08-12. Yeast lariat debranching enzyme. Substrate and sequence specificity.. https://pubmed.ncbi.nlm.nih.gov/7519612/

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