A day in the life of the spliceosome

One of the most amazing findings in molecular biology was the discovery that eukaryotic genes are discontinuous, with coding DNA being interrupted by stretches of non-coding sequence. The subsequent realization that the intervening regions are removed from pre-mRNA transcripts via the activity of a common set of small nuclear RNAs (snRNAs), which assemble together with associated proteins into a complex known as the spliceosome, was equally surprising. How do cells coordinate the assembly of this molecular machine? And how does the spliceosome accurately recognize exons and introns to carry out the splicing reaction? Insights into these questions have been gained by studying the life cycle of spliceosomal snRNAs from their transcription, nuclear export and re-import to their dynamic assembly into the spliceosome. This assembly process can also affect the regulation of alternative splicing and has implications for human disease.

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Acknowledgements

Research in the authors' laboratories is supported by US National Institutes of Health grants R01-GM053034 and R01-NS041617 (to A.G.M.), as well as R01-CA158283 and R21-AR061640 (to Z.W.). The authors apologize to those whose work could not be discussed owing to space limitations.

Author information

Authors and Affiliations

  1. Department of Biology, Department of Genetics and Integrative Program for Biological and Genome Sciences, Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, 27599, North Carolina, USA A. Gregory Matera
  2. Department of Pharmacology, Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, 27599, North Carolina, USA Zefeng Wang
  1. A. Gregory Matera