Mechanism of Splicing of Unusual Intron in Human Proliferating Cell Nucleolor Pl2O
Abstract
In the past year I have concentrated on the mechanisms of recognition of splicing enhancers, which are relevant to both conventional and non-conventional intron splicing. Three novel classes of exonic splicing enhancers (ESEs) recognized by human SF2/ASF, SRp40 and SRp55 have been identified by an iterative functional selection procedure. These ESEs are functional in splicing and are highly specific. In most cases,only the cognate SR protein can efficiently recognize an ESE and activate splicing. An interesting exception is that SRp40 selected ESEs can function with either SRp40 or SRp55. UV-crosslinking competition and immunoprecipitation experiments showed that SR proteins recognize their cognate ESEs in nuclear extract by direct and specific binding. A motif search algorithm was used to derive consensus sequences for ESEs recognized by each SR protein, and to show that such consensus sequences occur at high frequencies in exonic regions, particularly those corresponding to naturally occurring, mapped ESEs. Multiple high score motifs were also found in the proliferating cell nucleolar antigen (P120) gene exons, including those adjacent to the non-conventional intron F. Future studies will focus on the identification of splicing factors essential for the function of splicing enhancers, either in the context of conventional or non-conventional introns.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1997
- Accession Number
- ADA340957
Entities
People
- Hongxiang Liu
Organizations
- Cold Spring Harbor Laboratory