title: Cap-dependent RNA splicing in a HeLa nuclear extract.
abstract: We have studied the involvement of the 5' cap structure in the splicing of precursor mRNAs in a HeLa nuclear extract. We show that precursor mRNAs are spliced efficiently only when they possess a cap structure and that preincubation of a HeLa nuclear extract rendered the splicing reaction highly sensitive to inhibition by cap analogues. This sensitization was dependent on exogenous Mg2+ but not exogenous ATP or GTP. These results demonstrate that splicing in a nuclear extract is highly dependent on the cap structure, as was demonstrated for the splicing process in a HeLa whole-cell extract [Konarska, M. M., Padget, R. A. & Sharp, P. A. (1984) Cell 38, 731-736], and thus support the contention that cap recognition is an important feature of eukaryotic mRNA biogenesis.
mesh_terms: D000255:Adenosine Triphosphate / Q000494:pharmacology; D002467:Cell Nucleus / Q000378:metabolism; D006367:HeLa Cells / Q000378:metabolism; D006801:Humans; D008274:Magnesium / Q000494:pharmacology; D015636:Magnesium Chloride; D012314:RNA Cap Analogs / Q000494:pharmacology*; D012315:RNA Caps / Q000494:pharmacology*; D012326:RNA Splicing / Q000187:drug effects*; D014158:Transcription, Genetic
chemical_list: D012314:RNA Cap Analogs; D012315:RNA Caps; D015636:Magnesium Chloride; D000255:Adenosine Triphosphate; D008274:Magnesium