A Mammalian Activity Required for the Second Step of Pre-messenger RNA Splicing

摘要: Abstract Splicing of precursors to messenger RNAs occurs via a two-step mechanism. In the first step, 5′-exon is released concomitant with production lariat intermediate, and in second exons are joined, releasing intron form product. Several gene products yeast Saccharomyces cerevisiae have been shown be required exclusively for step. Although mammalian proteins implicated step splicing, none act only at this We identify here activity The was increase by 5-fold rate splicing whereas it had no effect on not affected treatment micrococcal nuclease, sensitive heating 55°C, suggesting that dependent an RNA, but more likely protein. separated from other factors PSF, factor thought activity. does require ATP hydrolysis, acts late stage splicing.