Dr. Tracy Johnson’s laboratory is focused on understanding the basic mechanisms of gene expression, particularly the molecular events underlying RNA synthesis and processing. Using the unicellular eukaryote Saccharomyces cerevisiae as a model, her lab has leveraged a combination of genetics, biochemical and bioinformatics approaches to understanding how the splicing “machinery,” the spliceosome, undergoes dynamic rearrangements to recognize and remove the non-coding intron sequences from pre-messenger RNAs. Recently, the Johnson lab has focused on how splice site recognition and the dynamic rearrangements of the spliceosome occur co-transcriptionally, while the RNA polymerase is still actively engaged with the chromatin template and are analyzing the effect that this has on pre-mRNA splicing outcomes. Finally, Johnson’s lab is interested in how all eukaryotic cells exploit integrated gene expression mechanisms to respond to their environment. To this end, they are using molecular tools and modeling approaches to understand these elegantly coordinated processes.
Selected Cancer-Related Publications:
Brangwynne CP, Johnson TL. The micro and macro of RNA function. Mol Biol Cell. 2013 Mar;24(6):679. doi: 10.1091/mbc.E13-01-0012.
Hossain MA, Chung C, Pradhan SK, Johnson TL. The yeast cap binding complex modulates transcription factor recruitment and establishes proper histone H3K36 trimethylation during active transcription. Mol Cell Biol. 2013 Feb;33(4):785-99. doi: 10.1128/MCB.00947-12. Epub 2012 Dec 10.
Merkhofer EC, Johnson TL. U1 snRNA rewrites the "script". Cell. 2012 Jul 6;150(1):9-11. doi: 10.1016/j.cell.2012.06.017.
Johnson TL, Vilardell J. Regulated pre-mRNA splicing: the ghostwriter of the eukaryotic genome. Biochim Biophys Acta. 2012 Jun;1819(6):538-45. doi: 10.1016/j.bbagrm.2011.12.011. Epub 2012 Jan 9.
Gunderson FQ, Merkhofer EC, Johnson TL. Dynamic histone acetylation is critical for cotranscriptional spliceosome assembly and spliceosomal rearrangements. Proc Natl Acad Sci U S A. 2011 Feb 1;108(5):2004-9. doi: 10.1073/pnas.1011982108. Epub 2011 Jan 18.