A genome-wide analysis indicates that yeast pre-mRNA splicing is predominantly posttranscriptional.
Recent ChIP experiments indicate that spliceosome assembly and splicing can occur cotranscriptionally in S. cerevisiae. However, only a few genes have been examined, and all have long second exons. To extend these studies, we analyzed intron-containing genes with different second exon lengths by using ChIP as well as whole-genome tiling arrays (ChIP-CHIP). The data indicate that U1 snRNP recruitment is independent of exon length. Recursive splicing constructs, which uncouple U1 recruitment from transcription, suggest that cotranscriptional U1 recruitment contributes to optimal splicing efficiency. In contrast, U2 snRNP recruitment, as well as cotranscriptional splicing, is deficient on short second exon genes. We estimate that > or =90% of endogenous yeast splicing is posttranscriptional, consistent with an analysis of posttranscriptional snRNP-associated pre-mRNA.
Tardiff
Daniel F
DF
Biology Department MS008, Howard Hughes Medical Institute, Brandeis University, 415 South Street, Waltham, Massachusetts 02454, USA.
Lacadie
Scott A
SA
Rosbash
Michael
M
D000199:Actins / Q000235:genetics; D001483:Base Sequence; D047369:Chromatin Immunoprecipitation; D005091:Exons; D016681:Genome, Fungal; D008969:Molecular Sequence Data; D012322:RNA Precursors / Q000235:genetics* / Q000378:metabolism; D012323:RNA Processing, Post-Transcriptional; D012326:RNA Splicing; D012331:RNA, Fungal / Q000378:metabolism*; D017412:Ribonucleoprotein, U1 Small Nuclear / Q000378:metabolism; D017413:Ribonucleoprotein, U2 Small Nuclear / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics; D017381:Spliceosomes / Q000378:metabolism
C465210:Act1 protein, S cerevisiae; D000199:Actins; D012322:RNA Precursors; D012331:RNA, Fungal; D017412:Ribonucleoprotein, U1 Small Nuclear; D017413:Ribonucleoprotein, U2 Small Nuclear; D029701:Saccharomyces cerevisiae Proteins