Hicks Martin J, Yang Chin-Rang, Kotlajich Matthew V, Hertel Klemens J
Department of Microbiology and Molecular Genetics, University of California Irvine, Irvine, California, USA.
PLoS Biol. 2006 Jun;4(6):e147. doi: 10.1371/journal.pbio.0040147. Epub 2006 May 2.
RNA processing is carried out in close proximity to the site of transcription, suggesting a regulatory link between transcription and pre-mRNA splicing. Using an in vitro transcription/splicing assay, we demonstrate that an association of RNA polymerase II (Pol II) transcription and pre-mRNA splicing is required for efficient gene expression. Pol II-synthesized RNAs containing functional splice sites are protected from nuclear degradation, presumably because the local concentration of the splicing machinery is sufficiently high to ensure its association over interactions with nucleases. Furthermore, the process of transcription influences alternative splicing of newly synthesized pre-mRNAs. Because other RNA polymerases do not provide similar protection from nucleases, and their RNA products display altered splicing patterns, the link between transcription and RNA processing is RNA Pol II-specific. We propose that the connection between transcription by Pol II and pre-mRNA splicing guarantees an extended half-life and proper processing of nascent pre-mRNAs.
RNA加工在转录位点附近进行，这表明转录与前体mRNA剪接之间存在调控联系。通过体外转录/剪接试验，我们证明RNA聚合酶II（Pol II）转录与前体mRNA剪接的关联是高效基因表达所必需的。含有功能性剪接位点的Pol II合成RNA可免受细胞核降解，推测原因是剪接机制的局部浓度足够高，足以确保其与核酸酶相互作用时的结合。此外，转录过程会影响新合成的前体mRNA的可变剪接。由于其他RNA聚合酶不能提供类似的核酸酶保护，且它们的RNA产物显示出改变的剪接模式，转录与RNA加工之间的联系是RNA Pol II特异性的。我们提出，Pol II转录与前体mRNA剪接之间的联系保证了新生前体mRNA延长的半衰期和正确的加工。
