Functional group substitutions of the branchpoint adenosine in a nuclear pre-mRNA and a group II intron
UMass Chan Affiliations
Howard Hughes Medical Institute, Program in Molecular MedicineDocument Type
Journal ArticlePublication Date
1997-08-01Keywords
AdenosineBase Sequence
Guanosine
*Introns
Molecular Sequence Data
RNA Precursors
*RNA Splicing
RNA, Messenger
RNA, Nuclear
Substrate Specificity
Life Sciences
Medicine and Health Sciences
Metadata
Show full item recordAbstract
Splicing of nuclear mRNA precursors (pre-mRNAs) takes place in the spliceosome, a large and complex ribonucleoprotein. Nuclear pre-mRNA splicing and group II intron self-splicing occur by a chemically identical pathway involving recognition of a specific branchpoint adenosine and nucleophilic activation of its 2'-hydroxyl group. The chemical similarity between these two splicing reactions, as well as other considerations, have suggested that the catalytic core of the spliceosome and group II introns may be related. Here we test this hypothesis by analyzing splicing and RNA branch formation of a pre-mRNA and a group II intron in which the branchpoint adenosine was substituted with purine base analogues. We find that replacement of the branchpoint adenosine with either of two modified adenosine analogues or guanosine leads to remarkably similar patterns of splicing and RNA branch formation in the two systems.Source
RNA. 1997 Aug;3(8):861-9.